Winter Time Machine: Animal Tracking in the Snow

Coyote in in the snow

Winter in Yosemite

Winter is the quiet time in Yosemite. Days are short, there are fewer visitors and many of the animals spend a lot of their time hidden. Ground squirrels, bears and, of course, cold-blooded animals hunker down in hibernation or torpor for the winter. In very cold places, toads will burrow as deep as three feet to hibernate.

Some animals are active all winter, but nevertheless usually hidden. Meadow voles and mice live out much of their winters in the space that forms between the snowpack and the ground, the subnivean layer. There the warmth from the ground and the insulating layer of the snow keep the temperatures around freezing and the snow protects them from the elements. Unfortunately for the mice and voles, though, long-tailed weasels are well-adapted to hunt in the subnivean layer with their long, skinny bodies and keen sense of smell.

Despite the seeming quiet, there is still a lot going on above the ground. Coyotes and bobcats hunt the meadows when snow cover is thin. Using their acute senses of hearing and smell, they locate animals below the surface and then pounce. The coyote makes a big arcing jump, coming down mouth first, diving into the snow and fairly regularly coming up with a small meal.

The Time Machine

The real pleasure of the winter, though, is the winter time machine – animal tracks. Why are tracks a time machine? Because they allow us to go back in time and see what has happened in the forest since the last snow. One of our winter pleasures is putting on our skis and getting out into the woods shortly after a storm. It’s often surprising how much activity there has been, even in just a few hours after the end of the storm. So while the cold and snow make harder to see animals, it is far easier to see signs showing which animals have recently been out and about and where they were going.

Squirrels

We know, a lot of people are not fans of squirrels, but they are nearly ubiquitous in North America so almost everyone who lives in a place with snow can track them. And squirrels are fascinating animals, fun to watch and to track, especially Theresa’s favorite animal, the chickaree or Douglas squirrel (Tamiasciurus douglasii), a close relative of the more widely-distributed red squirrel (Tamiasciurus hudsonicus). How could you not want to track this guy?

Chickaree or Douglas squirrel (Tamiasciurus douglasii) perched on a long in our yard in Yosemite West
Chickaree looking like what it is: a spring-loaded bundle of lightning ready to explode into motion.

The first thing to notice about squirrels is just how active they are as soon as the storm ends. On a sunny morning after a night of snowfall, the tracks will be everywhere. In the deep cold of winter nights, squirrels often congregate in group nests to stay warm, with males and females gathering in separate nests. But when day breaks, they are out and about. We actually see very few of them compared to summer, but the tracks let you peer into the past to see what they’ve been up to since the end of the storm.

Squirrel tracks also tell the story of how squirrels travel in snow. One thing to note is that the hind feet land in front of the forefeet when squirrels are bounding. Also tracks typically connect tree to tree, rarely passing through any real distance in the open. In soft snow, the squirrels climb a few feet up the tree and then hurl themselves off. We sometimes like to set our skis next to the tracks to estimate just how far they jump. Tom skis a 165cm (roughly 65-inch) ski and the jumps are commonly longer than his skis, so six or more feet.

Notice how the squirrel goes to the first stump, then launches for a full six feet leaving a mini crater in the snow, then goes to the next tree and jumps 3-4 feet at a right angle.

Why? In soft snow, squirrels are slow waders/paddlers and easy prey. They look like they are swimming, which effectively they are, which makes them slow and vulnerable in light snow. Being such agile climbers and jumpers, it takes less energy and reduces the amount of time they spend out exposed to raptors, bobcats and coyotes if they climb up a few feet and get the next six feet of travel practically for free and almost instantly and then race to the next safe spot.

In very deep snow, they can get even more creative. One time Tom was out alone in one of our favorite spots and in his far peripheral vision he saw what he first thought was a raptor diving from the sky. Instead, it was a squirrel coming in for a landing in what seemed like open ground. The squirrel had walked out along a branch that was maybe 10 feet long and 15 feet up and hurled itself off. In so doing it covered most of the 20 feet between the tree it started on and the sheltering branches of a young sapling buried in snow. As soon as it hit the ground, it started paddling through the snow like it was swimming in a race and soon reached the sapling. The gaps in the snowpack created by the branches of the sapling gave it ready access to the world beneath the snow and down it went, within a few seconds safe from surface hunters.

It’s rare that we get to see these travel jumps, but the tracks tell the tale. It’s easy to ignore such a common animal, but that very ubiquity is one of the things that makes it fun — you don’t have to be a squirrel whisperer to find some tracks to follow.

The great thing about tree squirrels is that they are active all winter and numerous. So it’s rare to go out in freshly-fallen snow and not be able to at least find a squirrel track to follow and study. And there always seems to be something new to learn even from this most common animal.


Mountain Lion Tracks

Mountain lion in profile
Historic photo of mountain lion in Yosemite (Dixon Collection, NPS, public domain)

In 20 years of living in Yosemite, neither of us has seen a mountain lion (cougar, puma), but fresh tracks in the snow right after a storm sometimes tell us that we have missed a cougar by less than two hours.

One time we saw impressively large cougar tracks come to a set of manzanita bushes. The group of bushes was about fifteen feet in diameter but only a couple feet tall. You would think the easy thing to do would be to a go around, but apparently not. We could see the normal walking track of the lion then, as it approached the bushes, the forefeet and hindfeet bunching together as the cat readied to spring, then nothing. On the other side, we found the bunched tracks of the landing, then back to walking along on its merry way. It looked like the 15-20-foot jump was as trivial as a yawn, not even worth a 20-foot detour to avoid. Sure, we never saw the actual cat, but the tracks gave us a feel for the awesome agility and power of the animal and our minds recreated the scene almost as if we had seen the cat itself.

Mountain lion tracks in the snow with a shoe for perspective
Tracking big cats in fresh snow above the Mariposa Grove!

On another occasion, Tom went for a morning run after a small dusting of snow from the night day and saw not one, not two, but three parallel sets of cougar tracks. That meant there were either three cats in the woods or one cat that has passed by three times in less than twelve hours. Both possibilities were sobering. He spent the rest of the run yelling and making noise (a few months later a park service game camera in the area captured three cats traveling together, probably a mother and two daughters).

While we have seen mountain lion tracks many times in the snow, we only have the one good photo (above). But we have taken some pictures of tracks here in Yosemite West. Note the three-lobed rear pad and the round footprint, clear signs of a cat.

Again, despite countless hours and miles in the forest and despite dozens of sightings of tracks, neither of us has ever seen one of these cats in the wild. But by paying attention to the tracks that let us go back in time and see who was in the woods shortly before us, we have had several “sightings” of mountain lions, disconnected in time.


Bear Tracks in Winter

Many people think bears hibernate all winter and are never active. We have seen bears down in Yosemite Valley in February feeding on a deer carcass from a mountain lion kill. If there’s food, males and non-pregnant females do not need to hibernate (technically, enter torpor as bears are not true hibernators). Up higher, at our house and above, there is almost never enough winter food, so all bears den up for the winter And yet, every winter, we see bear tracks in the snow.

Two bears in Yosemite Valley in February snow
February in the Valley. Deer carcass from a mountain lion kill is just out of picture. We watched these two, probably siblings, play fight, then eat, the play fight some more, then wander to the river to drink, then come back and eat and fight some more.

Bears, as it turns out, do not have watches or iPhones to tell them what day it is, so if they don’t have a den full of cubs, they get up and take a walk and, finding inadequate food, go back into torpor. They might also be out and about if their den was damaged or flooded and need to find a new place to bed down. In any case, we have never seen a high-country bear in winter, but we have seen their tracks in just about every month of the winter.

November

December

January

These are not as clear in the photo, but they are certainly bear tracks, certainly from January (2018) and sort of neat in that if you look you can see the claw marks.

February

We didn’t find any photos of March bear tracks in our library, but there might be some lurking there. In any case, we have seen bears or bear tracks in virtually every month, including not just in Yosemite Valley but up in the higher elevations. The February photos are from elevations of roughly 7000 and 8000 feet, respectively, with a heavy snowpack on the ground.

Also note that you can find bear “tracks” other places than the ground. Sometimes they scratch trees. One theory is that they are trying to show other bears how big they are so they can scare smaller bears off their territory. Not sure if that is just an old myth or has any real research behind it.

How big was the bear?

Interestingly, in this very snowy winter of 2023 we have been getting out more than usual, and yet we have seen no bear tracks since early December. Apparently very deep snowpacks makes for good sleeping.


Following a Fox and a Bobcat

One of our best tracking expeditions came after an early-season storm that dropped just a few inches of snow on otherwise bare ground. That meant we didn’t need skis and could follow tracks through thick forest. We soon found a fox track and followed it for a couple of hours which, at the slow pace we were going, was only about a mile and a half. Nevertheless, we learned a bit about foxes that day. In particular, the agility of this fox was incredible. It would jump up on a narrow log covered in snow and walk on it for a while before jumping down and continuing on. No terrain seemed to be an obstacle. At one point, a bobcat crossed the fox track. It tried to jump up on the same log as the fox, but could not match the fox’s agility and we saw the wide mark where it fell and slid down the far side of the log.

Unfortunately, we didn’t take pictures that day so we don’t have fox or bobcat tracks to show, but if you wander the woods enough, you might find your own!


Martens and Weasels

We have a “go to” area for quick hit ski tours close to the house which we have now been touring for 20 years. Conservatively, we have been there 100 times. Probably closer to 200. A couple years ago we first saw the distinctive 2×2 tracks from a larger member of the weasel family, either marten or fisher. In the 2021-2022 winter, we saw these tracks a couple more times. So, roughly speaking, we saw these tracks three times in 19 years. This year there has been an explosion in the number of these tracks. In a short couple miles of skiing, we typically see at least one set and commonly cross several sets just one day after a storm. Sometimes you can see where the marten drags its body through the snow, probably for the purpose of scent marking rather than just for locomotion and fun as otters (and ravens) do.

Since martens are fiercely territorial and will cover several miles each night criss-crossing their territory to hunt and fend off any interlopers, all these tracks are probably from a small number of animals. The size of an American marten’s range in the Sierra Nevada runs from as little as 0.7km2 to just over 7km2 (0.7-5.8km2 for females, 1.7-7.3km2 for males), depending on food availability. Roughly speaking, that means the range would be 1-3km across in general. Given the abundance of one of the marten’s favorite foods (squirrels) in these particular woods, the typical range is probably more in the middle of that range than at the high end, so say about a mile across, maybe less. But this year we have been seeing these tracks across an area that is several miles long. So it seems like our ski touring spots are home to a successful breeding couple. That’s fun if you’re a tracker, but less fun if you’re a squirrel!

Tom has actually seen a Pacific fisher a couple miles from this area and there are other verified sightings not too far away. So it is possible that these are fisher tracks, but martens are far more common, so it’s most likely these are marten tracks.

In most of the conditions we see these, it is impossible to tell them apart. To tell a marten from a fisher reliably, you need a very clear track and precise measurements. The size of their tracks overlaps and so does the distance between them (i.e. the length of their gait). In general, though, fishers have more “loading” on their feet. The feet are slightly bigger, but the animal is much heavier, so they tend to sink deeper. So even though the fisher is bigger, in deep snow, the fisher takes shorter steps and leaves a “ploppier” track. Based on that and the overall prevalence difference, we figure that we’re seeing the somewhat common Pacific marten rather than the rare Pacific fisher.

We also this year came across tracks that at first looked like just more squirrel tracks, which were abundant in the forest we were in. In the soft snow, the individual tracks were not clear, so you couldn’t see the shape of the feet or even the pattern they were landing in, but there were several indicators they did not belong to squirrels.

First, when they passed a tree, they did not take the classic squirrel strategy of climbing a short ways up and jumping off.

Second, they made long forays out into large open areas. Squirrels will venture into the open, but usually only for a short distance or when making a bee-line from tree to tree.

And finally, there were thin imprints of the tail. Squirrels generally leave no tail imprint, but if they do, it would be the bushy tail of the gray squirrel or the less bushy, but not yet thin, tail of the chickaree. With a few other clues, we decided we were most likely looking at the trail of a long-tailed weasel.

The video below was taken by our friend Rachel while hiking with us on Mount Hoffmann in July, 2020. I believe this is the closely-related short-tailed weasel, whose tail is generally one-third of body length or less while the long-tailed weasel tail is usually half as long as the body or more. That said, biologists studying the distribution of the two species in Connecticut found that sometimes they needed to do DNA testing in order to make positive IDs, as they species overlap in size and many other characteristics.

Weasel on Mount Hoffmann. Video by Rachel McCullough

We’re not entirely sure of this ID, but it seems likely to be one of the weasels, either short-tailed or long-tailed, and given that the latter is more common and given the tail-drag marks, we’re guessing that it is a long-tailed weasel. But in snow this soft, there was very little detail in the tracks, so this is just a guess.


Coyotes

Finally, Tom’s favorite animal to track is the coyote. He has tracked them for several miles, sometimes more than five. They will often stick to a line like they are following a compass heading. And they move fast. We know this because sometimes we see their tracks on the Badger Pass Road soon after the plow has passed or on the Glacier Point Road soon after the cross-country groomer has passed. Since we have a rough idea of when the plow passed and when we passed, we can ascertain that the coyote is on a mission, trotting along no slower than 6mph and probably faster. Tom’s theory is that the coyote is moving fast on a line through relatively open areas in hopes that one of the smaller critters with shorter legs will be struggling through the snow and the coyote can surprise it, overtake it, and get a meal.

Coyote in Yosemite West near our house

We recently (Feb 2023) saw some confounding tracks. From a distance, it looked like the 2×2 lope of a marten, but the size was too big. Upon closer inspection, we saw it was a coyote. Commonly in the snow, coyotes “direct register,” meaning that the hind foot lands in the spot just vacated by the forefoot on the same side. This increases their efficiency while moving through snow.

That’s one of the ways you can tell a coyote track from a domestic dog’s track. Domestic dogs, well-fed and comparatively uncoordinated, don’t need such efficiencies so are rarely precise in their registering, if they register at all. They also tend to have meandering tracks as they are excited to be outdoors and have no fears of wasting energy. Finally, their feet also tend to splay more because they simply have less-strong feet because they don’t spend all day everyday trotting along like coyotes.

So this track, which we followed for a couple of miles on Glacier Point Road was a bit perplexing. But we realized that the foot that failed to direct register was always the left hind foot. And the coyote would occasionally rest and then we would see it direct register and slowly get sloppier until it rested again. We also saw a place where it left the road and there was blood in the snow. At first we thought it was from a kill, but there were no signs of other tracks or fur or anything.

We finally guessed that the poor coyote had injured its foot and had minor bleeding, possibly from something as simple as snow building up and turning to ice that eventually irritated the foot. It also seemed at times to want to leave the road, but this was after a big storm. It would make a brief foray into the soft snow off the groomed cross-country ski trail and then return to the firmly packed road until, finally, it took a right turn and went off into the woods near Bridalveil Creek campground.

Much of that is just guessing, but it is fun to play detective while following an animal through the woods or, in this case, down the ski trail.

Did we correctly piece together the story of this coyote? We’ll never know, but the simple act of trying can deepen your experience of the land you move through and live in.


A Few More for Fun

Here are a couple more for fun. First a deer track. Deer seem to be rather inefficient walkers in the snow, dragging their feet and sinking deep on their small hooves. But as a general rule, they try to move lower for the winter and they often move in groups, which helps as they can take turns breaking trail. With the huge snows we’ve had this year, a lot of the animals seem exhausted. The deer in the video was alone, at relatively high altitude (about 5500 feet) and seemed very tired. When we drove home, she was lying in the road. It was sad knowing that two more feet of snow were forecast for the next day.

One tired deer who, sadly, doesn’t know that this sunny day will be the last for a long time.

The group of deer in the were lower and and had packed out trails around the river near Wawona and were doing much better.

At the other end of the size spectrum are the mice and voles. We don’t even try to identify species, but it’s impressive to see the distances they cover, almost floating on the snow with their delicate tracks. Mice leave tracks similar to mini-squirrels, often with a tail drag. Voles do not typically drag the tail and are often in a 2×2 pattern. So if there is a tail drag, it’s probably a mouse. If there isn’t a tail track it could be either one.

That said, the deer mouse is more likely to be out in the snow while the vole is more likely to stay snug in the subnivean layer. The last tracks in this gallery are funny ones: the little rodent was going along just fine until it came to a dropoff about a foot high left by the cross-country grooming machine. The critter just walked off the cliff, leaving a big (or little actually) plop in the snow.

The first two sets of tracks pictured below just impress us for how far these tiny guys were willing to walk in the open on the snow with the potential for getting intercepted by a hawk or a bobcat. And where was he or she going? Why walk all the way to the tree just to walk back? Who knows?


Final Thoughts

Even though the forests can feel quiet in the winter, paying attention to the tracks brings them alive. Even more than in the summer, you can get a sense of who frequents these woods and what the rough proportions are between, say, squirrels and coyotes and fishers. If you live near a place that has undisturbed snow, a tracking outing is a great way to get to know the habitat.

Recommended Books

You can, of course just go out on your own, but having a decent tracking book can help get you started.

For our area, we really like Mark Elbroch, Michael Kresky and Jonah Evans, Field Guide to Animal Tracks and Scat of California (University of California Press: Berkeley, Los Angeles, London, 2012).

The Stokes guide is also quite good, but oriented more toward the East Coast. See Donald and Lillian Stokes, A Guide to Animal Tracking and Behavior (Little, Brown and Company: Boston, Toronto and London, 1986).

For a more compact option for the Sierra Nevada, the wonderful Laws Field Guide to the Sierra Nevada by John Muir Laws (Heyday Press, 2007) has some minimal information on tracks and scat.

Stormy Weather: Winter 2022-23

Yosemite Valley with snow and clouds

If you’ve been following the news from Yosemite at all, you know we’ve gotten a little snow this winter. We are awaiting the results of the April 1 snow survey, but it looks like we will be close to, possibly even beyond, the 1983 record of 224% of normal. It looks like we will be well beyond the 178% of normal we got in 2011, the second-highest snowpack in the last 40 years.

Fun Start, Tough Finish

It’s been a stormy winter from the start. We already had good skiing by December 2 and a first wave of atmospheric rivers with a mix of snow and rain in late December and early January. We were getting in some great days of skiing and animal tracking and generally enjoying a great winter in Yosemite, the highlight being a ski ascent of Mount Starr King.

But the big wave in the last week of February and first week of March resulted in heavy snow, closed roads, power outages, a bit of skiing, all around mayhem, and what seemed like endless, endless shoveling. In the first phase, we got several feet of snow, lost power for four days, got it back for a day, lost it for another day, then got it back. In the second phase we got heavy rain, which was good because we simply had no place to put more snow and people were starting to worry about roofs collapsing. We could no longer clear the driveway with the snowblower because it would not throw snow over the 8-9 foot banks.

Theresa skiing in Yosemite West
The naïve smile, the blissful ignorance on the first big storm day before we really knew what was coming

Nobody could keep up and we had what we think is the fourth-longest park closure in our 20 years living here (as of April 7). Only the two Covid closures in 2020 and the Ferguson Fire closure in 2018 lasted longer. We believe it is the longest winter closure since the flood of January 1997 closed the park for three months.

Most people understand that when six to eight feet of snow falls in a couple of days, it can take time to get roads open. But this set of storms added a couple other elements into the mix. First, they came at the tail end of an already snowy winter with big piles of snow everywhere already, the roads already narrow, and the ground already saturated. Second, they lasted, with a couple breaks, for two weeks. Third, the combination of big snows and big rains meant that in addition to all the complications of digging out the snow up at altitude, down low there were mudslides, rockfalls, road washouts and a massive wet-snow avalanche across the road between Tunnel View and the Valley Floor. So road crews were spread unusually thin across the whole range of altitudes in the region.

All of this overwhelmed workers, equipment, systems, basic infrastructure and, no doubt a lot of poor critters. We saw the rarest of things — a pocket gopher above ground, looking rather unhappy wandering around on top of seven feet of snow. The poor guy was probably flooded out of his home (pocket gophers normally do not venture out of their tunnels except to find a mate, which was most definitely not what was happening on this day).

A very sad-looking pocket gopher on top of the snow in the yard

There are a lot of obstacles to getting the park open that might not be obvious. Before welcoming the public, crews had to dig out enough bathrooms and trashcans for basic sanitation. There are also over 200 fire hydrants that need to be located and dug out. The park emergency communications system depends on remote repeaters powered by solar panels with battery backup, but all the solar panels were buried and some difficult to access. In our neighborhood, we simply could not pile the snow high enough to make viable turnarounds in the cul-de-sacs, which is important for emergency vehicles to access the area. A myriad of little problems like that, in addition to the big ones like washouts and avalanches, had to be solved one by one until finally the park could handle an influx of people.

While it was all work and no play for a period of a couple weeks, we did manage before and after to spend a lot of time out in the woods and mountains skiing. For a couple weeks when the park was closed, we were limited to places we could ski to from the house, but before and after that, we’ve had a chance to get out and see Yosemite in winter glory like we have not seen since 2011. See below for a small gallery of photos.

What does this mean for summer 2023? That’s still unclear in the details, of course, but it most certainly means great, maybe historic, spring and summer waterfalls, a long wildflower season, snowy trails up high, and late road openings. As with all things, some good, some bad (though, as Hamlet says, Act II, Scene 2, “There is nothing either good or bad, but thinking makes it so,” and for our part, we rather like not having a drought summer for a change!)


Washburn and Oak Fire Information

Smoke plume above meadow

Aftermath

While the Washburn fire managed to get all the publicity because of its proximity to the Mariposa Grove and because it was inside the park boundary, it was generally what we would consider a “good” fire. It burned through heavy forest, some of which had no recent burn history. No mature sequoia trees were lost. This is the kind of fire that rejuvenates our forests.

The Oak Fire was another matter. Burning outside the park in the community of Mariposa, it received less media attention, but destroyed 193 buildings, including around 100 family homes. That included the home of someone we both worked for part-time in our early days in Yosemite. One hundred homes may sound like a small number, but we are a small county of 18,000 people. Proportional to LA County, that would be like losing 54,000 homes.

So while we ourselves were not threatened at all by these fires and only had a few weeks of heavy smoke impacts, it was a sad day for our larger community.

Update: Aug 2, 2022

Short version: the fires in the Yosemite region are all doing very well, have remained within the control lines for at least a few days now and are producing little smoke. Air quality is very good and everything in the park that was closed by the fire has reopened. No sequoia trees were lost and the Mariposa Grove, including the grove shuttle, has reopened. The one exception is the Washburn Trail, which is where the fire started, presumably because of hazardous trees.

We have long since resumed our normal activities. Tom went for a nice 9-mile run on July 30 with great views and we have resumed climbing and running and hiking and are taking a few days off next week to go backpacking. Conditions are currently excellent.

Washburn Fire

The Washburn Fire started July 7 and currently stands at 4,886 acres. It has seen no growth in four days and has only grown 30 acres in the last 10 or 11 days. It is 97% contained and the remaining 3% is burning in rocky terrain at low intensity within the control lines. Fire crews have almost fully demobilized from that fire.

The official source of information, as for all wildfires on federal lands, is the Inciweb page for the Washburn Fire. As the Washburn crews demobilize, there is no longer a daily briefing because for all intents and purposes, this fire is done. You can view the actual operations briefing for the fire crews on the YosemiteFire Facebook page.

Oak Fire

The Oak Fire started July 22 and currently 19,244 acres, which is unchanged over the last few days. Almost all residential areas have been repopulated, with a couple of small exceptions as fire crews continue to work on a small section on the NE flank and as the power company crews try to secure the electrical system in communities that were hit by the fire. The NE flank is still not marked as controlled, but according to the recent morning briefings, they have made a lot of progress and are in a mop up mode as they strengthen and deepen those lines until they feel confident to declare it contained.

The best source of information on the Oak Fire is on the CalFire Oak Fire Incident page. You can view the daily operations briefing on the CalFireMMU Facebook page. These briefings are usually under three minutes and give a great overview of what’s happening on the fire.

Western Fire Chiefs Association fire map. Super helpful map that shows very clearly growth from the current day, the previous day and prior to that. You can also click on the fire and it will give you growth in the last 24 hours. This is a national map that updates in real time as new data is released.

Smoke Impacts

Smoke impacts tend to be most intense during periods of fast fire growth and these fires have been no exception. During the fast-growth phase of both fires, we had really really bad air. After a respite and some great conditions as they got a handle on the Washburn, the Oak put an end to that.

Air quality in the last several days has been good to excellent. We have generally been within the EPA “Good” range, which means better than most days in Los Angeles. If we are going to have bad air, it will not be from these two fires.

Air quality can vary a lot with conditions (wind direction, fire intensity, inversion layers). Air quality forecasts tend to be rough estimates and much less accurate than weather forecasts.

  • Real time air quality from AirNow.gov (search on Wawona, CA, to zoom in on the right spot). This map shows both regulatory-grade and low-cost sensors. The regulatory grade are more accurate. The low-cost sensors are mostly Purple Air, which tend to be way off without the woodsmoke correction factor. It is better to view those on Purple Air and apply the proper correction.
  • Purple Air. These are cheap sensors that can be way off, but there are more of them in more places, so they help round out the picture. If you compare the regulatory-grade sensors in Wawona and Yosemite Valley to Purple Air sensors right near them, you can see a major variance. Sometimes Purple Air is very low. Sometimes it is very high.
  • Smoke Forecast. From Hanford weather station. Take with a grain of salt, but these forecasts seem to be getting better each year.

Winter 20121-2022 Gallery

Cabin with several feet of snow on top and giant sequoias around

Early Snow, Mariposa Grove New Year… and nothing until April

We had a promising start to winter with a couple of feet of snow in early December and then about three feet just after Christmas.

For several years, we have known that you could camp in the upper reaches of the Mariposa Grove (above the Clothespin Tree) in winter. But whenever we had time, there was no good snow and when the snow was good, we didn’t have time. This year we finally made it happen and spent New Year’s Eve in the Mariposa Grove.

Then it all dried up. Instead of shoveling, Tom was taking allergy medication because of the heavy pollen. By April 1, the snow survey crews were reporting 41% of normal snowpack. It turns out we did a poor job of documenting the melt off, so the one picture taken while climbing will have to stand in for three months without precipitation.

Fortunately, we finished with an unusually snowy April with over two feet of snow, most of it falling in a single late-April storm. It was enough to get in one last ski. We’ll see soon how that impacts the May 1 snowpack, but we’re hoping the cold weather and additional snow will help us claw back a bit from that low April 1 snowpack.

Tom snapped the last photo up at the Yosemite West guardrail at the end of the storm on his way back from plowing after one of the smaller storms.

All About Antlers!

Mule deer buck with large antlers

Spring visitors to Yosemite, looking around and seeing only deer with no antlers, sometimes ask rangers, “Where are all the bucks?”

People more familiar with deer will know that bucks lose their antlers in late winter and regrow them over the course of the spring and summer. So when you see a deer in March, whether male or female, you won’t see those characteristic antlers.

Pause for just a second to think about how amazing it is that these animals regrow and then shed their antlers every year. Deer antlers are unlike anything else in the mammal world. They are among the fastest growing tissue in the entire animal kingdom. They are not just majestic, but also fascinating to medical science and to casual observers like us! 

And that’s just the beginning. Did you know scientists can get mice to grow antlers? Do you know about the unique antlers of Yosemite’s most famous deer ever? Did you know that some Asian deer don’t have antlers at all, but something much scarier?

Look at these two guys below who stopped by the house on April 26 with just their short spring antlers. We don’t know at this point how large these antlers will get.

A healthy, mature male with excellent nutrition will grow these out to a majestic “rack” with over three feet of “spread” by September. Mule deer average about a quarter to a half inch per day of antler growth throughout spring and summer.

Other members of the deer family (Cervidae) are even more impressive. In a single day, elk can grow an inch of antler and moose can add a full pound. Still, this is nothing compared to the extinct Irish Elk (actually a deer, not an elk). It could grow and regrow antlers up to twelve feet (3.5m) across.

Skeleton of Megaloceros giganteus
The massive antlers of the extinct deer Megaloceros giganteum in the National Museum of Science and Nature in Tokyo, via Momotarou2012 on Wikimedia under the Creative Commons 3.0 License with various lighting adjustments.

Just how do they do that?

That’s just what scientists trying to understand bone growth, regeneration, and other basic science questions want to know.

Wait, Antlers are Bones?

Yes! Antlers are bones. People sometimes confuse antlers with horns, but they are very different. Horns are mostly keratin, the protein that makes up hair, claws, hooves, feathers and, yes, horns. Horns are found on both males and females, grow continuously, are permanent, hollow, and grow from the base. They are found in cattle, bison, buffalo, sheep and several other mammal families.

Antlers are altogether different. Antlers are unique to deer and only found among males except in reindeer, including caribou. Most uniquely, though, they are shed and regrown every year.

That requires a significant outlay of energy and nutrients for the male deer. Just like other bones of the body, the thickest part of the antlers have a spongy interior that contains bone marrow, which is where the body makes blood cells. In other words, the antlers are full-fledged bones that do all the things bones do.

During the growing phase they are soft and made up mostly of water and protein. They are covered with “velvet” that is rich in nerves and blood vessels. As summer ends, antlers stop growing, mineralize and harden in time for “rutting” season when the bucks use their antlers to compete in pushing contests. The winner is the one who gets to mate.

Wondrous Velvet

Close-up of mule deer face with velvet still on the antlers, deer facing the camera
Mule deer at Housekeeping Camp in Yosemite Valley. Note the velvet. The antlers perhaps half grown out in this June photo..

The fuzzy velvet that covers a deer’s antlers during the growth phase is how all the nutrients get to those growing bones. Because these growing antlers are mostly water and protein, they are relatively fragile.

So in addition to having a rich blood supply, the velvet is full of nerves and highly sensitive. In fact, it’s so sensitive that deer can be seen gingerly avoiding branches and brush in order to avoid injuring the velvet. This helps ensure they get a nice, symmetrical rack to increase their chances of mating in the fall.

We might think that antlers are a formidable weapon for defense, but that’s only true once they harden and shed their velvet. Their main purpose is to challenge other bucks during the rut and to display dominance, not to fight off coyotes. If a buck in the velvet phase is forced to fight off a predator, he will actually fight with his hooves and protect those antlers from damage. They are too precious to risk in a fight, and too soft and too sensitive to be effective anyway.

It is only late in the season, when the antlers are fully formed and hardened and ready for contests with other bucks that the velvet dies and falls off. And what does a deer do with that discarded velvet? It eats it. Can’t let all that good protein go to waste!

Mule deer with dying velvet shedding off antlers
Velvet sheds once antlers fully harden (NPS Photo, public domain)

The Life Cycle of a Yosemite Deer’s Antlers

Of course, this cycle is more or less the same everywhere, though the timing might differ a bit here and there due to climate.

  • March. Bucks shed antlers as early as January, but rarely. Shedding is most common in March.
  • April. New growth starts 2-4 weeks after shedding.
  • July. First forking of antlers is achieved. Before this, all bucks will have just a single spike. Once they reach full size, they will begin to harden and mineralize.
  • September. Antlers have grown to full size and strength. At this point the velvet dies and bucks then start “horning” brush and trees to scrape it off.
  • October or November. Necks swell to prepare for rutting contests.
  • November to January. Rutting Season. Mostly a pushing contest where the goal is to drive the rival to his knees. Once achieved, the dominant male “runs” a female for several days until she lets him mate with her. Once that’s done, he starts running another female. This lasts into January, sometimes into February.
  • Once the mating season is over, the bucks shed their antlers and the cycle starts all over again.

Notice in the photos below how the bucks sparring in the top photo from September still have thin necks. In the second photo, where they are in it for real, the necks have thickened and are ready for the real contest.

Where Do All the Antlers Go?

The deer population of Yosemite probably numbers in the thousands. If only a thousand bucks are shedding 2,000 antlers every year, where do they all go? You would think that 2,000 antlers shed year after year would start to become a bit of nuisance. Why don’t we see them all the time on hikes?

There are a few reasons. The first is that the deer don’t follow our trails, so a lot of the antlers end up in places humans don’t frequent. In addition, the deer often go to lower altitude to shed antlers. Still we see deer tracks in our area all winter, so they must be shedding antlers in our area.

So after many years, shouldn’t there be antlers everywhere?

Mature, hardened antlers are about 40% protein and 60% minerals. That makes them a great nutritional supplement for squirrels and other rodents who do not have subscriptions to Amazon Prime and can’t get their calcium supplements delivered by UPS. Also, rodents need to gnaw in order to maintain their teeth. When they find an antler, they gnaw on it. Porcupines are particular fans of deer antler, but in our area they only inhabit the lower reaches of the deer’s range. That leaves squirrels as the great recyclers of all that calcium, phosphorous and protein tied up in deer antlers. And thanks to them, the woods are not littered with years of antler accumulation.

Ground squirrel in Curry Village
Ground squirrel in Curry Village. Thank his kin for taking on the job of cleaning up all those antlers the deer litter throughout the park every year.

What would happen if there were no squirrels? It turns out that we know the answer. The squirrel population of California generally and Yosemite in particular was devastated by disease in the early 1920s. For years at a time into the 1930s, as few as a single pair of squirrels were seen in Yosemite Valley. The grey squirrel almost went extinct in much of California. In 1925, a few years after the collapse of the squirrel population, park naturalist Carl Russell went walking an area where deer were known shed antlers. He found more than two dozen single antlers in less than a mile without leaving the trail. Without the squirrel helpers to break down the antlers, they apparently did start to accumulate in the 1920s.

Antlers and Medical Science

Antlers are the only appendage that any mammal regenerates. They also grow faster than almost any tissue in the animal kingdom and are probably the fastest growing bone in the world. You can see why scientists are interested in antlers. If we understood antlers better, we might conceivably be able to regenerate a lost finger, heal broken bones faster or prevent and reverse osteoporosis.

Scientists have long known that there was something special about the cells at the base of the antler, the pedicle, from which the antler regrows every year. In the 1960s, researchers transplanted pedicle cells to the leg of a deer and it started to grow an antler on the leg! Even more surprising, they have transplanted pedicle cells to the forehead of a mouse and guess what? The result is this somewhat disturbing picture of a mouse with a sort of unicorn in its head. Do not try this at home!

Lab mouse with "antler" between the ears
Mouse with transplanted antler stem cells. Image from “Tissue Interactions and Antlerogenesis: New Findings Revealed by a Xenograft Approach,” by Chunyi Li, A. John Harris, and James M. Suttie, Journal of Experimental Zoology 290:18–30 (2001)

More recently, scientists have discovered the key genes that allow the deer to grow bone so quickly. In 2018, researchers at Stanford identified one gene that promotes the exceptionally rapid growth of antlers and another that promotes the exceptionally rapid hardening of antlers. Both of these genes are present in humans and linked to bone development. Understanding them better could lead to therapies for osteoporosis and other bone diseases.

And that’s not all. There could even be implications for cancer research. Why can’t other mammals regenerate appendages? Nobody knows for sure, but deer commonly suffer from deformities or uncontrolled growth of their antlers. It appears there might be some sort of tradeoff. You can have rapid growth and regeneration, but it might come at the cost of being more susceptible to that other form of rapid growth, cancer. So the study of deer antlers might have clues to what causes runaway cell growth and how to control it.

More Fun Facts About Antlers

  • If a deer is injured in the right front leg while the antlers are growing, the right antler will be deformed or stunted. But if the deer is injured in the right hind leg, the left antler will be deformed or stunted.
  • Mule deer antlers can weigh over 30 pounds, much of which is calcium.
  • To get all the calcium they need for their antlers, deer take it from their own bones, by preference non-weight-bearing bones like ribs. This means they get temporary osteoporosis every year.
  • Antlers have been important to humans for thousands of years – they are one of the primary tools used for flintknapping, that is making arrowheads, spearheads and the like from flint and obsidian.
  • The number of points on an antler do not indicate the age of the deer. In general, antlers get larger with age up until about 5.5 years old (the buck’s sixth summer) then stabilize. As a deer ages they can get smaller each year.
  • Age is only one determinant of antler size. The other big one is nutrition. Calcium is important, but during the growth phase antlers are mostly protein, so protein availability really affects antler size.

And the Really Crazy Stuff

If you’ve made it this far, now we get to the really crazy stuff! Here’s a quick bit about Yosemite’s most famous deer and deer species that don’t grown antlers at all, but something much scarier looking.

Yosemite’s “Rhino Buck”

Unquestionably, the most famous deer in the history of Yosemite was an ancient old buck people called Old Horny. He got his name because he had a third antler growing out of his forehead. Three-antlered deer are rare, but not unheard of. Typically, however, the third antler grows out of the frontal bone like the other two. Old Horny is believed to be unique in that his third antler grew out of the nasal bone.

He was much beloved by visitors in the 1920s who frequently fed him buttered toast, back when feeding the animals was a standard part of a national park visit (please don’t revive that tradition!). When he finally died, it was discovered that he was exceptionally old. His teeth had been ground all the way down to the gums, a sign of extreme old age in a deer.

That’s not a surprise — antler deformities are more common as deer age and Old Horny’s twisted antlers were another testament to his advanced age.

Saber-toothed Deer?

What could be stranger than a three-antlered deer? How about a saber-toothed deer! If you live in parts of Asia where the water deer come from, or in the UK where they are considered invasive, you might know about deer with tusks. For most of us in North America, though, the thought of innocent little Bambi with deadly tusks is a bit unsettling.

Stuffed Chinese water deer head with tusk
Bambi would have been a much less heartrending story if Bambi had sported tusks like these!

How in the world do you end up with a saber-toothed deer? There are in fact several species with tusks. It turns out, that antler size correlates to the size of the animal and, below a certain size, antlers are just not effective fighting tools. All the deer with tusks are under 15kg.

They also live in dense forests or jungle and are solitary rather than herd animals. This is important because antlers allow for bloodless competition among bucks. Herd animals do not want to shed blood, because they do not want to draw predators to the herd. Also, deer with antlers tend to live in open areas where they can display their large antlers from a distance as a dominance display. In tight vegetation, there’s no advantage to a big rack visible across distance and it just gets hung up in the vegetation. So these small, solitary jungle dwellers have tusks.

It turns out that ancient deer may have had both tusks and antlers, but as they evolved, one came to dominate based on the size, habitat and social life of the deer. However, even our nice Bambi mule deer have to potential to grow tusks. On occasion, hunters who kill a mule deer find that in fact it has canines up to an inch long. In other words, the basic genetics for tusks remains latent, it just is not expressed since antlers are so much more useful in the places mule deer live, like Yosemite.

All of that is somewhat theoretical, but it’s the best guess of the scientists who published the wonderfully-named most recent research article on this: “Stabbing Slinkers: Tusk Evolution Among Artiodactyls,” by Doreen Cabrera and Theodore Stankowich in Journal of Mammalian Evolution, Vol. 27, Iss. 2,  (Jun 2020): 265-272.

Wrap Up: Your Turn.

I hope all that deepens your knowledge of our deer, and yours too if you have them near your home. I also hope that the images of the “stabbing slinkers” will not trouble your dreams!

There’s a lot more one could say about antlers, but maybe we already said too much. Our goal with these articles is to expand people’s knowledge and appreciation of the natural world around them. We find these explorations interesting, but maybe you would rather read about different things. If you have ideas for things related to Yosemite nature or history that you would like to read about, let us know by email or in the comments. We would love to read your suggestions!


Read More

There are countless articles about antlers on everything from the Smithsonian website to hunting blogs. A lot of state departments of wildlife have nice pages too. These are some fun articles as well as some of the more esoteric, academic sources that played into this article.

Fun and not too scholarly:

A bit on the more esoteric side:

The Evening Primrose Nature Show

Evening primrose close up

Coming to Yosemite to watch flowers open may sound like the beginning of a joke — Did you hear the one about the guy who went to Yosemite to watch the flowers open?

And yet, when the deer are kind to us, watching the evening primroses open in our yard is one of our great pleasures of summer. The nightly show is so stunning that it was once one of the principal attractions of Yosemite, rivaling Half Dome and the giant sequoias with visitors in the early 1900s. And then, just as Yosemite became world-famous for those blooms, they were gone forever. The story of the evening primrose and how they mostly disappeared touches on a surprising range of topics from the history of the Ahwahneechee, their expulsion from Yosemite, the commercialization of the park, the history of color and motion picture photography, and ultimately humans’ relationship to nature. That’s a lot for one little flower.

Read on to learn about evening primroses.

  • Part I: The Natural History of the Evening Primrose
    • Why is watching a flower exciting?
    • A bit about their ecology
  • Part II: Cultural History: The Rise and Fall of Evening Primroses in Yosemite
    • How they came to be a major attraction in Yosemite around 1900
    • How they came to disappear
    • What the story of the evening primrose says about the human presence in Yosemite and our relationship with nature

Part II really gets down in the weeds (bad pun, I know), but if that does not interest you, you can just look at the pictures and videos. Do not skip the video.

What’s so exciting about watching a flower blossom?

In the case of Oenothera elata, aka Hooker’s evening primrose, the yellow blossom almost the size of the palm of your hand opens most of the way in just a few seconds. When people see video of an evening primrose opening, they usually think it’s a time-lapse. On the best nights at our house, it happens over 100 times in about 40 minutes.

A few years ago, our friend Russ of Yosemite Hikes fame took this one-minute video in our yard. It will give you a sense of how fast the evening primrose opens. This real time, not a time lapse:

Real time video of an evening primrose opening and a sphinx moth arriving

This shorter video is a time-lapse that shows a five blossoms opening in 15 minutes and 17 seconds, compressed into about 12 seconds.

Evening primrose time-lapse. Total real time: 15:17.

Basic Evening Primrose Ecology

The evening primrose is a biennial. The first year it grows with just a basal cluster of leaves — no stalk and no flowers. It’s just putting out leaves and captures as much solar energy as it can, storing that energy in its roots for the big show the next year.

That second summer, it uses the stored energy and the new energy coming in to grow as high as four feet tall. Each plant can have a few dozen blossoms, with just a few opening each evening at sunset over the course of about a month. The blossoms last for only one night.

Why wait until sunset to open? Because the plant doesn’t want it’s precious pollen and nectar taken by day-flying pollen thieves (no judgement, this is just what botanists call an insect that takes pollen and nectar without pollinating the flower). To be effective gathering and spreading the gooey, filamentous pollen strands of an evening primrose, the insect needs to be properly equipped. No insect is so well-equipped for the task as the sphinx moth, who we will meet in a moment.

These blossoms really are intended for the night flyers first and foremost — in the full heat of the summer, the blossoms will be wilted and “dead” by 11am, sometimes earlier.

The pistil, that long thread with the cross at the end (called the stigma) in the middle of the blossom, is the pollen receiver. If you pull it out, the filament is 2-3 inches long. Around it are the stamens with a sort of gooey pollen that sticks to the moths and travels with them to the next blossom. The pollen grain brushes off on the cross-shaped stigma, then travels all the way down that tube to the ovaries to fertilize the seeds. It has to complete that journey overnight before the flower wilts.

The plant then makes hundreds of seeds for every seed pod. The pods eventually dry out and open and that tall plant, blowing back and forth in the wind, ejects the seeds a fair distance, like Father O’Connor spraying the congregation with holy water.

evening primrose blossom closeup
You can see the stamens laden with pollen. That sticky pollen holds onto the moth and the moth carries the pollen grains to the next blossom.
closeup of evening primrose blossom
The same blossom in Sentinel Meadow, from a different angle, showing the pollen on the stamens better.

More on the evening primrose

Is that a bird?

Notice the supporting cast in that video. It looks almost like a hummingbird when you first see it flying, but you will soon see that it is the gorgeous White-lined Sphinx Moth (Hyles lineata).

hyles lineata dorsal view
Hyles lineata, by Didier Descouens via Wikimedia Commons under the Creative Commons Attribution-Share Alike 4.0 International license.

The sphinx moth’s secret weapon is a very long proboscis that lets it reach deep into flowers that have a large nectar reward. They are known to frequent columbines and we have seen them on pennyroyal, but the evening primrose is clearly a favorite. The sphinx moth is a major evening primrose pollinator. In return, the evening primrose provides food not just for the adults who come for the nectar, but for the caterpillars as well.

Hyles lineata with long proboscis feeding on nectar
The impressively long proboscis of the White-lined Sphinx Moth. Photo by Larry Lamsa from Flickr and Wikimedia Commons and used under the Creative Commons Attribution 2.0 Generic license.

Their timing is impressive. We rarely see these moths, but within minutes of the first blossom opening, they arrive. To our human noses, the smell of the evening primroses is subtle, not like the powerfully-scented flowers like azalea or pennyroyal. Apparently for a sphinx moth, it’s like Mama Ciccardi’s famous marinara sauce cooking on the stove on a summer evening — within minutes, the smell wafting from the flowers calls them to dinner from the far corners of the neighborhood.

Other pollinators

The sphinx moth is not the only pollinator. We see other insects in the flowers sometimes, but typically only in the morning. Carpenter bees (specifically Xylocopa tabaniformis) can be a major pollinator. The overlap in the range between the Xylocopa tabaniformis and the Oenothera elata suggests this is an ancient relationship developed through long co-evolution (Barthell and Knops). In our experience, though, it is the sphinx moth who rules the skies over and around the evening primroses when they open.

When does this happen?

In drought years and wet years, hot years and cool years, the first blossoms are always within a couple of days of Theresa’s birthday at the end of June (The exception to this rule is this record-breaking snow year of 2022-2023 when as of July 3, there are still no seed pods showing). The show reaches its peak in early July and goes strong through most of the month and fades by early August, after which it’s just a few blossoms here and there. We’ll still get the occasional blossom into October, sometimes on plants that appear all but dead.

Where does this happen?

The evening primrose is not a rare plant, but it is a favorite food for deer. So while widespread, there are typically only a handful in Yosemite Valley that blossom each year. A century ago, that number was in the thousands, perhaps tens of thousands or even more, but those days are gone (that’s the story of Part II). To the best of our knowledge, the best places to see them are just east of Tioga Pass along Highway 120 (a terrific display there in good years) and at our house, except in those years like 2021 when the deer ravage “our” plants (they aren’t our plants of course, any more than we are their humans).

Taxonomy: a primrose by any other name

The evening primrose is not closely related to the primrose, just like the primrose is not closely related to the rose. They are three distinct flower families belonging to three separate orders. Roughly speaking, that means they share a great-grandparent. The evening primrose is actually somewhat more closely related to the rose than to the primrose. To get technical, roses (Rosaceae family) and evening primroses (Onagraceae family) both belong to the Rosids clade, while primroses (Primula family) belong to the Asterids clade.

Part II: The rise and fall of Yosemite Valley’s flowers

Today’s visitor often comes to Yosemite in hopes of seeing a bear, but very few people make the trip to Yosemite in hopes of seeing a flower open at sundown. In the early 1900s, it was the reverse. There were no bears in Yosemite Valley. When a bear did enter the Valley, most people thought it should be chased off or killed as soon as possible.

Meanwhile, they ranked wildflowers up there with El Capitan and Yosemite Falls as a must-see attraction. The wildflowers of Yosemite Valley inspired some of the earliest color photographs and the world’s first time-lapse movies of flowers. Indeed, time-lapse photography was virtually invented in Yosemite by Arthur Pillsbury, who held a photographic concession in the park from 1906 to 1922.

Among all the flowers of the park, the evening primrose was one of Pillsbury’s favorites. When he first came to Yosemite, he found entire meadows that would turn yellow as the flowers opened en masse. Our small patch on its best days sees 140 blossoms open in 40 minutes, peaking at perhaps 7-10 blossoms per minute. How big were the massive displays of Yosemite Valley, reputed to have turned entire meadows yellow? One hundred blossoms in the peak minute? Five hundred? Probably thousands at the peak.

Field of evening primroses in Yosemite Valley with Half Dome behind
From Arthur Pillsbury’s book, Picturing Miracles of Plant and Animal Life (Philadelphia: J. B. Lippincott Press, 1937). Sadly, I can only find black and white reproductions of Pillbury’s hand-tinted color photos, like this one of the evening primroses in Yosemite Valley, with Half Dome rising in the background. The black and white photo does not do it justice. The quality of this image and the brilliance of the colors are stunning. If one of the Pillsbury tinted “orotones” goes on display in the Yosemite museum, as they periodically do, it is worth some effort to get there to see it.

Wildflower Tourism at the Turn of the Twentieth Century

Wildflowers were such an integral part of the Yosemite experience that when the National Geographic Society ran an article about the park in their weekly Geographic News Bulletin (vol. 1, n. 9; 3 April 1922), they titled it, “The Park of a Thousand Flowers — Yosemite,” and noted that “Yosemite National Park is beloved especially by children because of its many flowers.”

Photocopy of the start of the Geographic News Bulletin article on Yosemite
The Park of a Thousand Flowers!

It seems strange, in our era of video games and Red Bull athletes to think that children were drawn to Yosemite for the flowers, but apparently it was so which speaks to a different aesthetic in 1922 than in 2022.

That publication was aimed at teachers and clearly some read it. Later that year, The Western Journal of Education (vol. 82, no. 7, p. 8-9) ran an article on “Yosemite National Park for the Educators” that described Yosemite Valley in these terms, highlighting the central importance of the evening primroses (my emphasis):

Decorate these walls with titanic structures — El Capitan, Half Dome, Sentinel Rock, Cathedral Spires, Cathedral Rocks — chiseled smooth as glass in many places, then stud these walls with foaming cataracts that flash in the sun, Yosemite Falls… Bridal Veil…. Carpet the meadows with Mariposa lilies and evening primroses and other blossoms which have made Yosemite known as the “Park of a Thousand Flowers.” This is Yosemite Valley.

Western Journal of Education, 1922

In short, for the visitor of 1922, the flowers of Yosemite Valley rivaled El Capitan and Yosemite Falls in majesty in a way that is rarely the case a century later.

The Decline of the Evening Primrose

And yet, by the time these publications came out in 1922, the golden age of the Yosemite Valley flowers was over. In the Handbook of Yosemite National Park from 1921, the great botanist Willis Jepson wrote regarding the evening primroses (my emphasis):

One of the remarkable sights of the upper reaches of the Valley in midsummer are the fields of tall yellow Evening Primroses… In favorable seasons the dry open fields about Yosemite are often yellow with these stately plants. Many of the finest groups, however, are now a thing of the past, due to the mowing of the meadows for wild hay.

Jepson, Handbook, p. 254

In her 1929 survey of flowers in Yosemite Valley, the naturalist Enid Michael noted that, “June of the year 1920 witnessed the last great bloom on the floor of the Valley” (Giddens and Heady, p. 25). Joseph Dixon, writing in 1934, said that in a survey of Yosemite Valley in the late 1920s, only six evening primrose plants had been found in the whole valley (Dixon, p. ?? [get page no. from copy in Yosemite Research Library]).

A few years later, the Wildflower Man of Yosemite himself, photographer Arthur Pillsbury, wrote (my emphasis):

Unhappily this Primrose is now almost extinct in the Yosemite meadows. The mowing machine took its toll and since it has been put on the protected list the deer have acquired a fondness for the leaves, not hesitating, either, at blossoms.

Pillsbury, Picturing, p. 54

What was still a highlight of a Yosemite trip in 1910 had all but disappeared by the 1920s. The naturalists lamenting the loss of the evening primroses typically point to two factors: farming and deer.

Why did deer become a problem for Yosemite flowers in the 1920s? What changed? Why were there so many flowers in 1910 and why were they all but gone by 1922?

Flowers in the Valley before 1900

After the glaciers receded, Yosemite Valley was a wetland or a lake. As the lands silted up and the waters receded, there is some evidence of ancient forest in Yosemite that was wiped by either rock slides or fires, either natural or manmade (Gibbens and Heady, p. 8-9).

For at least a few thousand years, inhabitants of Yosemite Valley set fire to the meadows annually, typically in the autumn. This made it easier to harvest fallen acorns and promoted the growth of plants with edible bulbs and tubers. Many of the common flowers we know today were prized as root crops, like Elegant Brodiaea (Brodiaea elegans), Blue Dicks (Dichelostemma capitatum), Mariposa Lilies (various Calochortus species), and many more. See the wonderful article by M. Kat Anderson and Frank K. Lake on the various “geophytes” (roughly speaking, “root crops”) prized and eaten traditionally in California.

The meadows were also important for plants such as dogbane (Apocynum cannabinum). Dogbane was not an important food crop. As the name suggests, it’s poisonous at least to dogs. It was essential for making twine which could be used to make baskets, nets, traps and anything else requiring rope. It was therefore an essential material for the residents of Yosemite Valley.

The Valley was sometimes described as “swampy,” but the new guardians of the Valley brought changes. It’s likely that swampy crops like onion were common, though they are rare today in Yosemite Valley. Meanwhile, those same moisture levels made the meadows inhospitable to the native pines, firs and oaks. The Ahwahneechee practice of burning the meadows also kept tree encroachment at bay.

It appears that the Ahwahneechee used fire to hunt the deer in Yosemite Valley, and probably elsewhere (Ernst, p. 39). So the fire that kept the trees from overtaking the Valley also indirectly helped keep the deer population down and, therefore, prevented the deer from eating so many of the Valley’s flowers. Oral tales speak of the Ahwahneechee going up to the Valley rim to hunt for deer, presumably because deer were not sufficiently abundant on the Valley floor.

As soon as the burning stopped, the size the of the meadows started to decrease. The European-American methods of controlling the brush through cutting was far more labor intensive and far less effective than burning. It was impossible to keep the overgrowth at bay and the meadows began to fill with brush and forest. A survey in 1868 found that there were 745 acres of meadow in Yosemite Valley. By 1937, only 327 acres of meadow remained (Gibbens and Heady, p. 24).

In addition, the European-Americans changed the hydrology of the Valley. Blasting the recessional moraine near El Capitan in 1878 for the express purpose of draining the Valley had a major impact on the meadows. Raised roadbeds disrupted the flow of water. Utility pipes often cracked and were abandoned, leaving them to take in water and channel it out of the meadows (Gibbens and Heady, p. 8 and passim). With the drying came more brush, more trees, and fewer flowers.

All of these changes that came with the expulsion of the Ahwahneechee combined to create a Valley floor that had far less meadow and much more undergrowth than it had had in perhaps thousands of years. Still, the 1937 state of the Valley was far less forested than what we have become accustomed to in the twenty-first century. The result was undoubtedly a greater quantity of flowers than we know today, but beyond that we mostly know only about the species that were used for food, and precious little even about those.

Yosemite Valley from Invasion to National Park

After the Ahwahneechee attacked a couple of trading posts, the Mariposa Battalion invaded Yosemite Valley in 1851 and forced the Ahwahneechee out for the first time. The tribe returned that winter, but most were forced out definitively in 1852. Though a small number resided in the Valley into the 1960s, they effectively lost control of their lands and therefore the meadow burning stopped in the 1850s and the meadow drying began soon after, with the consequences we’ve just seen.

Those consequences did not, of course, happen immediately. In 1855, just four years after the initial invasion by the Mariposa Battalion, an early tourist wrote that Valley was rich with strawberries:

The wag of our party said that any man who would find three feet square in a space of six hundred acres, where we encamped, that did not have the strawberry on it, should have the pleasure of shooting through his hat. The search was made for the space; but our friend says his hat will never have a hole through it from this proposition.

Reprinted in Browing, p. 219.

In 1864, Yosemite Valley became a California state park, but it was managed much less actively than today. Despite its status as a park, settlers and business people soon began grazing cattle and horses and plowing for crops. At least 20 acres of El Capitan meadow were plowed and sown with fodder for horses and cattle. Many other meadows were plowed or used as pasture for both horses and cattle. By 1887, 150 acres of Stoneman Meadow was under active cultivation. People began to complain and in 1890 new rules were passed to reduce farming in Yosemite Valley. Nevertheless, the government plowed and planted Ahwahnee Meadow from 1910 to 1914. Other meadows were not plowed, but they were mowed for “wild hay” as late as 1924 (Gibbens and Heady, pp. 4, 21-22).

Man with a plow and team of two horses with Half Dome in the background
Photo of US government electrician Sam Cookson plowing Ahwahnee Meadow in 1911 or 1912. Public domain photo from NPS collection.

Despite this history of plowing and mowing, Yosemite Valley nevertheless had breathtaking displays of flowers, with the evening primrose as one of the stars, perhaps the star of the show. How is it, then, that the evening primroses thrived in the presence of mowing, and yet disappeared about the time mowing stopped?

Naturalists of the time point to two factors. First, before the mowing ended, it moved to new locations and wiped out some of the best surviving collections of flowers. Second, the deer population boomed. By the time the plowing and mowing stopped, the number of deer was sufficient, as it is now, to all but eliminate the evening primrose from the valley.

Yosemite Valley: Death Trap to Animals
(Or: Why the Deer Didn’t Eat All the Flowers in 1900)

We think of deer as numerous and ubiquitous in Yosemite Valley, but it wasn’t always the case. As we saw in the discussion of Ahwahneechee practices, deer had probably been rare on the Valley floor for hundreds, perhaps thousands of years. With the influx of settlers and their guns in substantial numbers, deer along with most large animals, were hunted to extinction on the Valley floor.

Though the national park had been created in 1890, Yosemite Valley remained a state park under state management. Rules against hunting were widely ignored. In 1905, Yosemite Valley became part of Yosemite National Park. The next year, the U.S. Army, who managed the larger national park, took over management of Yosemite Valley as well. In his 1906 report, Acting Superintendent Major Harry Benson reported to Washington about the conditions he found on taking charge of the Valley (my emphasis):

The Yosemite Valley itself has, during recent years, been a death trap to all game that was unfortunate enough to enter it. Practically every person living in the valley kept a rifle, shotgun, and revolver, and any animal or bird that was unfortunate enough to enter the valley was immediately pursued by the entire contingent, and either captured or killed. A bear pen constructed about three years ago was found by me within 400 yards of the Sentinel Hotel.

During the early part of September two bears entered the valley, causing great consternation among those people who had been living here for some time, and they all seemed to think that these bears should at once be pursued and driven out.

Benson, Report, p. 10.

To make matters worse, during those years, the army only managed the park from May through October. The rest of the year, only two rangers oversaw the entire park. Benson noted that, as the two rangers did little patrolling, “the game scarcely receives any protection from them.”

Those conditions were terrible for the deer, but marvelous for flowers. The valley floor was reputed to be white with camas lily in the early season and yellow with evening primrose in July. It was during this period that Arthur Pillsbury took his famous hand-tinted photos of evening primroses and, later, his time-lapse movies of them opening.

As late as 1908, Acting Superintendent Benson was still worried about the low deer population and intensive hunting. But from 1909 on, the annual reports of the Acting Superintendents repeated every year that the deer population was increasing. This hurt, above all, the evening primroses. As we have found in our yard, the deer seem to love this plant as much as we do. Of course, the process took time. In his 1910 book, The Yosemite Valley, Galen Clark still noted that the evening primrose was “very common in Yosemite.”

After about 1910, the evening primroses faced greater pressure from both deer and mowing. Initially, the rise of the automobile reduced the need to grow hay and graze the meadows as there was no longer a need to feed and stable the horses that brought tourists to Yosemite (Gibbens and Heady, p. 5). At the same time, the burgeoning tourist trade in Yosemite required fresh milk and meat. In the days before refrigerator trucks, fresh milk and meat required local cattle (and a slaughterhouse, from which Slaughterhouse Meadow in Yosemite Valley gets its name). And local cattle needed hay.

Despite the predations of the plowman and the deer, however, the flower remained an attraction. The July 31, 1922, issue of Yosemite Nature Notes still suggested that visitors go out into the meadows to watch the evening primroses open.

Sounding the Alarm in the 1920s

By the 1920s naturalists in the park had sounded the alarm: the flowers were disappearing. In response, the park service and the concessioner made various attempts to hold onto the tradition of Yosemite’s great flower displays. In the early 1920s, Yosemite’s Curry Company tried to plant wildflower gardens in Curry Village with poor results: “Although plants commonly grazed by deer were avoided, the project was abandoned after three years of unsuccessful attempts to keep out the deer.” (McLelland, Chapter 4, section “Grounds of the Concessionaires”).

During the planning of the Ahwahnee Hotel, a 1927 memo called for a “plant refuge” around the hotel because, “It is well remembered that the meadows many years ago were filled with evening primroses” and other plants (McClelland, Chapter IV, my emphasis). Note that already in 1927, people thought of the spectacular blooms as something that happened “many years ago.”

After a rough start, the plants were fenced in to protect them from deer and elk, the latter having been introduced into Yosemite. In 1929, Horace Albright, the new director of the National Park Service, commented that the Ahwahnee plant refuge was “‘the only place in the valley where native flowers’ could ‘be seen in any profusion’” (ibid.). Around 2010, as I was relating some of this history to long-time ranger Bob Roney, it sparked a memory. He told me that the evening primroses were still there in the early 1970s and, though he didn’t know the history, he remembered watching them open from a seat by the window in the Ahwahnee Dining Room the night he proposed to his wife.

Meanwhile, the park service began maintaining flower exhibits behind the new museum, first with cut flowers gathered from around the park and, beginning in 1929, with a live garden protected from deer. The garden expanded under the direction of naturalist-ranger Enid Michael. In 1935, the curators planted evening primrose. This collection of now-uncommon flowers “became the object of popular evening walks” (McClelland, Chapter IV and Chapter VI).

During my ranger days, I would occasionally encounter long-time park visitors who remembered going to the museum garden in the evening to see the evening primroses open. In 1941, Enid Michael wrote an article for Yosemite Nature Notes (vol. XX, no. 4, p. 30-31) on the “Guests of the Evening Primroses,” about the carpenter bees and sphinx moths. She still waxed poetic about the show the flowers put on as the sun goes down, but she located that show in the Museum Garden, not in the meadows of Yosemite Valley as the author of the 1922 article had done.

Evening Primroses Today

Over time, even the Museum Garden and the Ahwahnee Hotel “plant refuge” disappeared. Now, only visitors with a sharp eye and good timing will find an evening primrose blooming in Yosemite Valley. Every year there is at least one place in the disturbed soil along the roads in the Valley that you can find an evening primrose that has survived the deer. By far the best collection near the park grows along the road just east of Tioga Pass. It is perhaps the last place where, on a good night, you can see hundreds of plants produce perhaps 1000 blossoms. The next best place is our house in a year when we succeed in keeping the deer away.

Humans, Nature and Evening Primroses

The story of the evening primrose in Yosemite raises some interesting questions about “natural” places and whether there is such a thing or, more precisely, whether there is a real difference between “natural” places and other places.

When I first came to Yosemite in 1985, I imagined I was walking through a landscape preserved through visionary action from time immemorial just as it always had been so I could appreciate it in its natural, almost primordial form. The naivete of that young rock climber shocks me now, but both the rock climber and the culture around him have evolved somewhat in the intervening forty years.

Of course, even the most superficial reflection reveals my naïve first impression to be untrue — a landscape formed by the Big Bang, plate tectonics and glaciers has no “original” form outside the Singularity. A slightly deeper reflection would have highlighted the obvious fact that there were virtually no uninhabited places in America in 1450 and still less so in 1850, so there was no primordial, untouched place to preserve in 1864. Still, I imagined that it had changed little over the last few hundred years, setting aside the accoutrements of industrial tourism such as roads, trails, hotels, vacation rentals and rangers.

The understanding that the place I thought of as stable could have changed so much in 150 years took years to appreciate. The hotels were obvious as was the absence of Ahwahneechee hunters. Only over time and with increasing knowledge of natural history, though, did I come to see that large patches of the Valley are almost entirely populated with cheatgrass (Bromus tectorum), which did not even exist in North America until the late 1800s. The common mullein (Verbascum thapsus), which grows widely throughout the Valley, was brought over by Europeans and planted as a medicinal (for stomach ailments). And many of the Valley meadows are full of Kentucky Bluegrass which, despite it’s name, is a Eurasian species, not a native of Kentucky let alone the Sierra Nevada. A century of fire suppression has radically changed the composition of our forests. They are far denser than before and biased toward small, shade-tolerant trees rather than the massive fire-tolerant (even fire loving) trees of the past.

All of that poses an obvious question: what do we mean when we talk about “natural” landscapes and going into the outdoors to experience “nature?” Is Yosemite today, with its roads, hotels, restaurants, exotic Eurasian plants, dense cedar and fir forests, and huge deer population, natural? Was the Yosemite of 1906, with no deer, plowed meadows and a magnificent show of evening primroses in unplowed areas, natural? Was the Yosemite of 1800, with double the meadow and a tiny fraction of the undergrowth that we know today thanks to annual fires set by the Ahwahneechee, natural? Was the marshy valley of 5000 years ago, before the arrival of people, ipso facto more natural than the dry valley that humans lived in? Do humans, by our very presence render a place less natural? It is now clear in the Anthropocene that there is no landscape that has not been influenced by humans, so how do we distinguish between a place like Yosemite Valley and a place like Manhattan?

Once you ask these questions, it becomes clear that simple words like “natural” and “wild” are inexact labels for slippery concepts. Better minds than mine have devoted entire books and careers to wrestling with those questions. Rather than hazarding an answer, I will end with a quote from historian William Cronon:

If wilderness can do this—if it can help us perceive and respect a nature we had forgotten to recognize as natural—then it will become part of the solution to our environmental dilemmas rather than part of the problem. This will only happen, however, if we abandon the dualism that sees the tree in the garden as artificial—completely fallen and unnatural—and the tree in the wilderness as natural—completely pristine and wild. Both trees in some ultimate sense are wild; both in a practical sense now depend on our management and care. We are responsible for both, even though we can claim credit for neither.

Cronon, The Trouble with Wilderness

And that is why I have avoided calling the evening primroses that grow near our house “our plants.” We feel responsible for them, but we cannot claim credit. They are their own plants.

Sources

Many sources are either cited in full or linked in the text. The sources that are mentioned just by author name are here given in full:

Yosemite 2021 Retrospective

Digging out my truck after big Yosemite snowstorm in 2021

Last updated: December 3, 2021.

There was no big surprise to the way 2021 started: with the park closed due to surging Covid. There was a bit of surprise to what happened next: a powerful windstorm that knocked down thousands of trees including some mature giant sequoias. That was followed by the one big snowstorm of a drought winter, some excellent skiing. We had a dry summer (of course), but less smoke and fire impact than the previous year and a gorgeous autumn.

For much of that time, the park had a day-use reservation system in place (May 31 to September 30), which changed the feel of the park substantially and resulted in some inconveniences, but overall was great for our guests.

Winter 2020-2021

Covid Surge

You’ve probably heard of this. The short version is that the park closed in mid-December and stayed closed until early January due to a Covid surge. The park might have opened earlier, but for a couple of other events…

Massive Windstorm

On January 18, we had a major Mono wind event that brought down thousands of trees, including several mature giant sequoias. The falling trees destroyed houses, public buildings, power lines, and blocked roads. Miraculously, the mayhem did not kill any people. If there was a silver lining to the park closure, that was it. Still, it did an estimated $200 million dollars in damage just within the park. Many houses were destroyed in the surrounding area too. Some people in Wawona, where they have above-ground powerlines, were without power for a couple of months.

Westfall Ranger Station destroyed by Mono wind event, Jan 18, 2021
Westfall Ranger Station, RIP

Drought Winter… with one big storm

Overall, 2020-2021 was an extremely dry winter. According to the final snow survey on May 1, the water content in the Tuolumne River watershed was 25% of normal and in the Merced River watershed it was 31% of normal (Daily Report, May 7). That made it one of the driest of our 18 winters in the park.

Fortunately, it wasn’t completely dry. We had a few storms, and one of them was a nice one!

We had three storms that dropped about a foot of snow each, a few storms that just dropped a few inches, but the highlight of the winter was a single storm that dropped seven feet at our house from late on January 27 to early morning on January 29. At the end, we had up to eight feet of snow in the yard as measured with an avalanche probe (6-8 feet depending on the location, sheltering trees and so forth). 

Digging out my truck after big Yosemite snowstorm in 2021
Almost free!

One of my (Tom) community service activities is to drive the snowplow when the full-time guys can’t. On the morning the snow ended, an avalanche closed the main highway they come in on. I had plowed until midnight and skied home, but they couldn’t make it so I put my skis back on to ski back up to the plow. In then end, NPS cleared the avalanche and the crew got there before me, so I got to ski home and have soup. This photo is on the main road in the neighborhood, up near the guard rail. It had been plowed less than 10 hours earlier.

Tom skiing up Yosemite Park Way to fetch the plow
Somebody’s gotta plow the roads!

We have seen a lot more snow than we did this year, but we believe that in our 18 winters in Yosemite, the seven-foot snowfall was second only to the 11-foot snowfall in late March 2011. 

As I said, that was still not enough to bring us out of drought. We expected that less than a third of our normal snowpack would lead to massive tree die-off, but it didn’t happen. The huge number of trees that died in previous years from beetle kill and drought must have already thinned the weak trees.

Summer in the Park

Day-Use Reservations, Limited Services, Lots of Peace and Quiet

From May 31 to September 30, the National Park Service required day-use reservations to enter the park for anyone who was not staying inside the park gates at hotels or rentals, in campgrounds, or backpacking. Of course, many potential visitors and the gateway community businesses found this quite hard and it did make it harder to get backpacking permits.

For our guests, who had guaranteed entry by virtue of an overnight reservation inside the park gates, it was generally a good thing. Yes, there were some inconveniences: shuttles weren’t running, there were fewer food-service options, there were fewer ranger programs and so forth.

On the plus side, there were fewer people. Based on the Year to Date visits (2.8 million through September 2021), it looks like 2021 will see a bit over 3 million visitors to the park by the end of the year. That would make it roughly equal to visitation levels in the late 1980s and well below the 4 million visitors we’ve had in recent years and far below the 5 million visitors who came for the NPS Centennial in 2016 (see stats for 1906 to 2020).

Not counting construction delays, there were basically no traffic jams and trails were less crowded, but many people who wanted to see Yosemite were not able to do so. So there was both good and bad.

We do not yet know what the plans are for 2022 in Yosemite. At a certain point, though, we as a nation will have to decide whether we want to let as many people as possible into our national parks at the cost of creating an unpleasant and degraded experience. Or will we limit access and preserve the experience, but shut out people who might want to come regardless of conditions? These are not easy questions. There have been times during the Covid restrictions when it felt like a few more visitors would not have been noticed. On the other hand, we cannot keep increasing visitation indefinitely. At a certain point, it’s just too much, as in 2016 when Yosemite “welcomed” a record 5 million visitors. Stay tuned.

Mariposa Grove Reopened

After being closed for almost three years for restoration (2015 to 2018), it was sad to see the Mariposa Grove closed again due to damage from the windstorm. The Mariposa Grove re-opened May 5, 2021. There was no shuttle service, which meant that it was (and continues to be) a two-mile walk to the first trees. But what a great experience for those who are up for the walk. We’ve never seen the Upper Grove so quiet during the summer. Normally, for that kind of solitude among the trees, you have to ski in. Of course, like the day-use reservations, it also meant that a lot of people who wanted to see the grove were unable to do so. There are no simple answers!

Fires and Smoke

Despite the massive fires in the state, conditions in the park were surprisingly good. We had a handful of really smoky days, but nothing like in 2020 when the massive Creek Fire raged just south of the park. This year there was no major fire activity in the park. The one big fire in the area was in Coarsgold about 45 miles away and it was early in the year, which meant there were a lot of resources available and things weren’t that dry yet. In short, we got lucky this year.

End of the Year

It’s not fully over as I write this on December 3, but all in all we had a gorgeous autumn. We would, of course, like more precipitation, but we got some good rainstorms and even a nice October snowstorm. Now we just need some snow so we can get out with our new backcountry ski boots!

Ferguson Fire Chronicle

Ferguson Fire day 2 from El Portal

In 2018, we made it through the Ferguson Fire without burning down and, in fact, with no damage whatsoever. No small accomplishment, though not through efforts of our own.

We get a lot of questions from guests about the evidence of forest fire they see while driving to our house. Someday we may add some articles on fire ecology and things like that, but for now, this is the story of how those burn areas along Wawona Road and Glacier Point Road came to be and what it was like for us.

Want all the gory details? Read on.

The Fire Starts

Whenever we go away in the summer, it is always with some anxiety.

Fire looms large in our minds as the creeks and vegetation dry out and news of California fires rolls in. Every summer, we think “This could be the one where we lose the house.” The idea of being away when that happens and not being able to grab passports and momentos encourages us to stay home during fire season.

For the last twenty years, though, I have gone to Michigan every other summer to teach my summer paleography workshop. This year, Theresa came with me so she could finally meet the folks I had been talking about for 20 years.

We left for Michigan on July 7, so on Friday, July 13, we were both away when we got news that a fire had started near Savage’s Trading Post. This is nine miles from our house, so it was a matter of some concern, but not major worry.

The only real problem was that early on the fire burned the main power lines to the region and we had guests in Alpine Escape. This is only the second time we’ve had a major event while we were away and fortunately, in both cases, our guests proved themselves to be self-reliant and adaptive people.

It was disappointing for our guests, but not yet the fire we had always feared — the one straight down the hill from our neighborhood. But that would come.

The next day, we found out that a firefighter had died, bulldozer operator Braden Varney, a well-liked local resident and friend of a friend. After the first 24 hours, the fire had expanded to 828 acres and was still many miles away.

Could it possibly reach Yosemite West?

The Fire Grows

By the time the morning map came out on July 17, representing three days of activity, the fire had covered six of the nine miles to our house and was lapping Pinoche Peak. There were now three miles and one ridge between the fire and our home.

Four days later, our neighborhood was placed under an evacuation order. By this time, we had left Michigan to spend a long weekend with Theresa’s parents in Minnesota. We cancelled our flight, not realizing that our long weekend would last 24 days!

Before the evacuation was mandatory, several kindly friends offered to swing by the house and grab things for us. Eventually, two neighbors actually came to our house and fully loaded our pickup truck and drove it to safety. It was more than we would have dared to ask, as their house was threatened too and they had plenty on their minds. 

There were nearly a dozen evacuated communities and, finally, on August 3, they ordered the evacuation of Yosemite Valley, only the second time in history that Yosemite Valley was evacuated due to fire.  There are four substantial residential areas that are inside the park gates: Yosemite Valley, Wawona, Foresta and Yosemite West. With the mandatory evacuation of Yosemite Valley, all four were now evacuated.

The last time the Valley closed due to fire, in 1990, that fire would ultimately destroy many of the houses in Foresta and Yosemite West narrowly escaped due to a shift in the wind.

Would this fire destroy Yosemite West?

Firefighters Draw a Line in the Forest

By July 24, things were looking positive. The fire was fully established on Pinoche Peak and in the drainage below Henness Ridge, the ridge right above our neighborhood. But firefighters had built dozer and hand lines all the way along their primary defense line on Henness Ridge. There were over 3,000 firefighters deployed. Things looked good.

Backburns

Over the next few days, the firefighters backburned along the entire line, starting at the top and working their way all the way down to Highway 140.

Backburns, or “tactical firing operations” as the fire people call them, widen and strengthen the line. Initially, they create a line anywhere from a handline the width of a narrow hiking trail to a dozer line the width of a road.

A fire can easily jump a line like that. So they try to wait until they have winds blowing away from the line, and then the set a fire using drip torches and a gas/diesel mix. Ideally, the wind pushes the fire away from the line and toward the main fire. The goal is a relatively low-intensity fire that will broaden and strengthen the line as it burns out fuels. When the main fire hits the burned out line, it is starved for fuels, runs out of strength and can be held there.

That’s the theory anyway.

In reality, a hot fire creates massive updrafts that throw embers high into the sky. On a recent hike at least a quarter mile from one of the backburns, we found the forest littered with charred bits of bark that had been wafted on the wind, but fortunately did not “spot” across the line. In extreme cases, a hot fire on a bad day can spot as much as a mile across the line.

This is why wildfires commonly leave a burn pattern that is a “mosaic,” a patchwork of burned and unburned areas. Sometimes, within the boundary of the fire, the vast majority of the area is burned only in the understory and large sections of many acres are not burned at all.

Back on the Line

By July 28, with firing operations complete along the line protecting our area, things were looking good and we got ready to return home.

We had dodged the bullet. Or so we thought.

Then, the fire operations map for July 29 showed a small bulge outside the containment line. The fire had slopped over the line and because of thick smoke due to a strong inversion layer, the firefighters had not noticed it.

The morning briefing was optimistic. They had crews in there and expected to contain it.

The rumor mill was saying otherwise.

Spotting Across the Line

Tragedy on the Line

Then tragedy struck. While cutting down a tree to contain the fire, the tree took an unexpected bounce and killed Brian Hughes, the much-loved leader of the Arrowhead Hotshots. This incredibly sad event, right in our area, cast a pall of sadness over the future successes.

With the forest thick with dead trees from bark beetle infestation and rocks rolling downhill, it was too dangerous to risk another life. So the crews pulled out.

With the inversion holding the thick smoke low and preventing pilots from seeing through it, there was no air support. They made the decision to let the fire run, hoping to stop it at road 03SO30X. We bike this road pretty often and estimated the chances of making a successful stand there as close to zero — it is a one-lane logging road where the trees branches often bridge from one side to the other.

Game Over for Yosemite West?

Over the next couple of days we watched as the fire approached road 03SO30X. On August 2, we anxiously waited for the day’s fire operations map to post online and saw that the fire had jumped the road and was now straight downhill of our neighborhood in dense forest with no significant barrier between it and our homes.

It looked like it was game over for Yosemite West.

Firefighters Make a Stand

Unlike 1990, this time, however, they had had three weeks to prepare a line on Henness Ridge, secure some exits routes, thin in the neighborhood. Also, over the past 12 years, residents have made a concerted effort to make our area more fire safe. Plus, the inversion was still slowing down the fire.

The firefighters decided to stay and fight.

I had never expected that decision and I would never has asked it of anyone. But the professionals on the ground had been planning for this night for three weeks and felt comfortable with their plan.

Now they just had to fight the fire they had always said they would not be able to fight. No big deal.

They fell back to their contingency lines, some quite close to the community. A firefighter told a friend who was in the neighborhood, “We’ve got a lot on the line tonight.” So, taking advantage of the nightly downslope winds, they walked into the forest and started setting fires along the contingency lines to burn out the fuels in advance of the oncoming fire.  There are countless ways in which this could have gone wrong, but inaction meant almost certain destruction. Afterwards, I told the fire chief, who had spent most of her career in fire forecasting, that I never thought it would work. She just smiled and said, “Yeah, me neither.”

All night long they set fires and then worked to keep them out of the neighborhood, watching for spot fires and generally keeping the fire from jumping the lines once again. The big question now was “Were the lines deep enough to hold off the flame front when it arrived?”

The Fire Arrives

After three weeks of nervous anticipation, late on August 3, the main flame front finally arrived at the Yosemite West lines.

Fortunately, in most areas close to the neighborhood, the fire did not crown. To the south, the fire made a hot run up toward Henness Ridge. To the north, it made another hot run. Firefighters witnessed a fire whirl (aka “firenado”) race up a drainage near Avalanche Creek. One of the firefighters who also happens to be our dental hygienists nephew, captured a fire whirl on video not too far from our area. 

The northern run jumped the Wawona Road and then in short order raced uphill and jumped the Glacier Point Road. If any of these hot runs had come straight at Yosemite West, I would likely be writing a very different chronicle at this point.

The fire also jumped Highway 140 and made a run toward the community of Foresta. To the far north, the fire encroached on Highway 120 west of Crane Flat.  That meant Yosemite Valley was cut off from all three western exits, leaving only Highway 120 over Tioga Pass open.

With Wawona Road and Glacier Point Road compromised, firefighters were cut off from their “spike camp” at Badger Pass and had to shelter in place in our neighborhood. This is exactly what they could not have risked if residents hadn’t spent the previous 12 years reducing the fuels in the neighborhood and firefighters hadn’t had three weeks to make additional preparations.

It is hard to describe just how much luck we had on our side.

An Anxious Night

As the fire passed to the north, one resident who stayed said that you could hear the roar of the fire all night long. We knew this was the big show.

We had done pretty well at going about our daily business, keeping up with our work remotely, enjoying dinner with family. This night, we fell asleep late, slept fitfully and awoke early, expecting that when the news of the day came, our home would likely be gone. Being two hours ahead, though, it was a long wait until the morning report came out.

Structures Lost

When the report finally came out, it updated the number of structures lost from one to eleven. We assumed that the neighborhood had been lost and that the low number was just a delay in reporting and that as the day wore on, the number would climb and bad news would roll in.

Slowly, we heard rumors that no houses had been lost that night. Finally, in the evening update on August 4, we read, “Fire burned to the north, east and west of Yosemite West. Firefighters were successful in protecting structures and ignited tactical fires to buffer both communities” (that is, Yosemite West and Foresta).

It turned out that a handful of abandoned mining shacks on the other side of the fire had been lost.

Out of Danger

By August 6, we were hearing fire managers finally say that they thought the danger to Yosemite West was past. There were still threats in Foresta, but generally, things looked good there.

We could finally really enjoy the family time we had left before going home.

Before the highway by our house could reopen, there was a long process of lighting backburns all the way down the Wawona Road to Elephant Rock, a defensible ridge that would let them reliably stop the fire before it entered Yosemite Valley.

There were also hundreds of hazard trees along the roads that had to be felled and countless hours of labor in improving safety and getting fire restoration crews into the areas that had been churned up by dozer lines and hand lines.

But for the communities involved, the stressful part of the fire was effectively over.

The next day, they lifted the evacuation on Yosemite West and we bought plane tickets to return from Minnesota on August 13.

What would we find?

People kept asking us how we would deal with smoke damage and things like that. We didn’t know.

Coming Home

We finally made it back home on the afternoon of August 14, after going into Yosemite Valley to pick up our truck that kindly neighbors had packed and driven out for us. A small section of Hwy 140 was very smoky, but mostly the forest looked good, with nice burning in the understory and very little crown fire.

The normalcy of everything was uncanny.

Within the neighborhood, everything looked as it had before we left. Standing on our porch and looking out, you could see no signs of fire except for charred pieces of ponderosa pine bark littering the ground everywhere, having been hurled high into the sky on the fire-fueled updrafts. Nothing told of the pitched battle that had raged there just ten days earlier. It all felt surreal.

We braced ourselves for smoke damage, but the worst of it for us was that our house had been closed up for 39 days in hot weather and smelled stuffy.

We expected to be hunkered down hiding from the smoke, but instead, we opened the windows and turned on fans to let the fresh air in and slept with the windows open. We couldn’t believe it.

But every rush of joy turned our thoughts to the families of Braden Varney and Brian Hughes and the fact that two men had died in the effort to fight this fire, one specifically in the fight to save Yosemite West.

Right across the street from our house, we found a new “trail.” That is to say, they had dug fallback handlines right near the house. As this was more of an emergency fallback line, it was all unburned around it and we walked it just for a look.

We were dubmstruck by the amount of effort that had gone into building that line and others around the community. This doesn’t count the miles of line that were on the edge of the fire and the miles of line that were eventually overrun. In addition to all the lines, they also laid out 85,000 feet of firehose. Again, it is hard to quite wrap my mind around the effort just to save some houses.

Aftermath and Recovery

It wasn’t until August 24 that the Wawona Road opened and we could drive through the hottest part of the burn area. It was a staggering contrast to the normalcy of our neighborhood and the Wawona Road in the other direction (toward Wawona). For about two miles, the bulk of the forest had burned.

In general, the forests of the Sierra Nevada must burn to stay healthy and the vast, vast majority of the area burned in this fire saw the healthy, low-intensity fire that rejuvenates the landscape. But the area where the fire had made the hot, fast run on August 3-4 was absolutely scorched.

But again, the ecosystem here has evolved not just to survive fire, but to need it. Many species simply cannot reproduce effectively in the absence of fire. Some seeds require heat or smoke exposure to germinate. They lie in the soil for up to 100 years waiting for a fire. Other species can sprout from their roots even with the entire part above the soil is burned.

We walked one of the dozer lines about two weeks after the fire had passed and saw oaks putting up new shoots around the stumps. The bitter dogbane was sprouting and flowering, while outside fire area,  the same species was turning yellow for fall. We saw large numbers of tracks from bears, mountain lions, coyotes, foxes, small mammals, lizards and snakes in the dusty ground, sometimes right in the ashes. Over the next few days we spotted two bears walking the edge of the burn area. Many oaks were dropping acorns early, which is good news for bears.

We are looking forward to doing some fire phenology and see what blooms when and what comes back first.

[2019 update: the spring of 2019 brought the most astounding wildflower displays we’ve ever seen — carpets of blue and yellow and white throughout the burn area]

The Kindness of Neighbors
The Efforts of Strangers

During the entire time, we were philosophical about losing the house. But we realized that we would also lose a community. The fire coming while we were away meant we depended on friends and neighbors to take care of things we would have taken care of ourselves under other circumstances. Countless people offered to help including, as I mentioned, several who went by the house to grab things for us, including two neighbors who entirely filled our pickup truck and drove it to safety so that if we lost the house, we would have clothes and camping gear.

While insurance would help us if we lost the house, our community would be dispersed and many would never come back. After the fire, when we saw neighbors and had a chance to gather, there was a feeling of having dodged a bullet, but also an appreciation of how special it is to have neighbors you care about and who care about you.

And then, finally, at the risk of sounding like a broken record, it is still hard to quite fathom the effort that so many people put into saving our community and others threatened by the fire. We never imagined that any team, no matter how dedicated and courageous, could stop a fire coming up the hill from below us, and yet they did. And they did so at the cost of two lives, one on the far side of the fire and one specifically in the effort to stop that fire that threatened our community. And they did so through the efforts of countless firefighters working the lines for sixteen hours a day in hot, smoky conditions, supported by a small army of logistics people. 

It is with profound thanks and awe that we remember the sacrifice of Braden Varney, Brian Hughes and all the other firefighters who contributed to saving Yosemite West and all the other communities in the path of the Ferguson Fire.