Leaves up and down

Virtually all the leaves are down now, though here and there I run across one that hasn’t dropped its leaves yet. Most of those show brown, crinkled leaves, but a few, like the maple in today’s photo, are still brilliant with color.

I suppose it’s too soon to identify which trees will have marcescent leaves through the winter and which simply haven’t dropped their leaves yet.  Marcescence is the term for trees that hold their leaves all winter, often until the new spring buds push the last of the old leaves off.  Some trees are notorious for marcescence—the American beech is one and oaks are another, both of which surround my cabin. Often, it’s the younger and smaller trees that are marcescent.   And frequently, it’s the lower branches only that retain leaves.

One theory (marcescence has many theories) is that retaining leaves helps protect the smaller branches from being eaten by deer and so helps a young tree retain its both branches and its health.  The idea here is that the leaves make it difficult for deer to nip the twigs. The dried leaves are less nutritious and even make their twigs less so.   Another theory is that oaks and beech trees have not fully mastered being deciduous yet and that marcescence is some evolutionary in-between stage.   Another theory is that marcescence helps smaller understory trees better retain and recycle their nutrients, keeping those goodies to themselves, which could be especially important to small trees with their smaller root systems.    

One thing about marcesence that is not theoretical is that the leaves provide shelter for birds in winter, helping to protect them from the wind.  That’s a result of marcescence, not a cause of course, though clearly the birds know how to take advantage of it.

A little light at night

Snow on marcescent American beech leaf

The snow of Sunday morning is gone, leaving in its wake weather warmer than normal for late December. The ski resort will likely not be able to open for at least part of the Christmas week, traditionally its biggest week of the entire ski season.

Crews make snow for 2-3 nights, then it rains and ruins it all. They make snow again for 2-3 nights and then it warms up and the newly-made snow melts. My weather forecast predicts rain and above freezing nights over the next few days. The crew needs temperatures below freezing by at least a few degrees for most of the night in order to make snow.

When crews make snow, the lights along the slopes are lit, and when they aren’t, all the lights are off. You would think I would see a big difference whether the lights are on or off, but most of the time I don’t. Over by my cabin, I get a fair amount of winter light from the night sky. It’s actually lighter at night in the winter without Roundtop’s lights than it is in the summer when all the leaves are on the trees.

Of course, a few leaves remain on the trees most of the winter. The American beech tree retains many of its leaves right up until the dead ones are pushed off the twigs by the new growth in spring. A few years ago I learned this is called marcescence, which means the leaves wither but don’t fall off.

Theories abound about the purpose of marcescence, but from what I’ve read nobody really knows why some leaves don’t fall off. Certain species, like beech, are more prone to it than other species. Younger trees and the lower branches also seem more likely to display marcescence.

Still, the vast majority of the trees have lost all their leaves, and that lets the light of the wintry night shine all the way down by my cabin.

Thaw

Likely this thaw won’t last. It’s not uncommon to have a January thaw in this area that lasts for several days or a week. We didn’t have a January thaw this year. It waited until February for that. If this thaw lasts more than a week or so, it will be both unusual and cause for concern. Rising sap could cause the buds to appear and everything from fruit trees to dogwood blossoms could then be damaged or destroyed when the weather returns to normal again.

But for a few days, I won’t worry about that just yet. For now, it was enough to be out in the sun on a warm day and enjoy a vacation from winter without ever leaving the area. At this point, one or two days into the thaw, there’s no sign of spring. There’s simply mud and decaying leaves, wet and flattened from weeks of being covered by snow and ice. This is a good thing. It means last year’s leaves are already turning into forest loam. Some years, when it is dry through the winter, last year’s leaves greet the spring still crunchy and not much decayed. A normally wet and snowy winter moves that process along nicely.

The other thing I noticed is the number of trees with marcescent leaves, such as those in today’s photo. In this area, that pretty much means I’m looking at a lot of American beech trees, though a very few others, often oak, will have them, too. Marcesence simply means that the trees hold on to their leaves until the new leaves push them off in the spring. Sometimes, as the new leaves are just starting to come out, you’ll see both the new leaves and last year’s leaves on the same tree.

Scientists argue about what causes marcesence and whether its effects are positive or negative. Sometimes one will say the effect is positive when another calls the same effect negative. I find their arguments interesting but so far have found nothing in them to get overly concerned about. Here on Roundtop, marcesence on beech trees simply is a normal way of the forest’s life.

The Old and the New

Those of you who guessed dogwood to my mystery photo from yesterday are correct. I guess the question was too easy. I thought it would be more difficult because of what was in the background of the photo—dead leaves on the forest floor.

When I was walking around and first spied the flowers down there, I thought what are those? It was only when I got closer that I realized the flowers weren’t growing out of the ground but were part of a tree. This particular tree is a victim of one of the winter’s ice storms. In fact, I thought the tree was dead because it’s broken in half, the top half resting on the forest floor. I’m certain that this tree will die, but somehow it managed to survive long enough to produce one last burst of flowers in the spring.

My photo today shows the last two marcesent leaves on a beech tree in my front forest (woodland living equivalent of a front yard). They look pretty funny surrounded by the green leaves of spring, but there they are, the very last two.

Winter's Last Gasp

The forest’s marcescent leaves are finally starting to come down. Some of the younger beech trees held onto their leaves the longest but even those are now starting to fall. This means the beech trees will soon produce their new leaves for this season. For the past few days, before the marcescent ones began to fall, the forest looked a little odd. Some trees were pretty well-leafed out or at least well-budded but others still held onto last year’s dead leaves. It looked like two seasons on display at the same time. Even in today’s photo, you can see the green shades in the forest behind this leaf.

I am noticing big differences in spring growth between what’s going on around my cabin and what’s leafed out down off the mountain. Off the mountain, the redbud is in full bud, but up where I am, the color on the buds is just beginning. The dogwood is much the same—very pretty down in the valley but still early on up where I am. And "up where I am" isn’t all that up. I live at about 1000-1050 feet above sea level, while the valley is around 300 feet above sea level. It’s not as though the altitude is profoundly different between where I am and where most people live, but it is enough.

It is different enough in other ways, too. And for that I am thankful. I have lived up here long enough that I don't think I could go back to living in the valley again. That I don't ever want to goes without saying. I have reached the point where I routinely wonder how anyone can live where nature is held at bay with lawns and box stores and highways. I am sorry to be the exception rather than the rule. Truly, "up where I am" is where I want to be. But sometimes I feel a bit like a marcescent leaf myself--the last one, still hanging on.

An Evening in the Woods

The rain cleared late in the day, and the evening was beautiful, if windy. As you can see, the marcescent leaves on this American beech tree in my front forest are still hanging on. I'm starting to see buds on a few of the smaller trees and shrubs, so these remnants of 2007 surely don't have long to hang on anymore.

Last night the red foxes were barking. I haven't heard them since last fall. The one was very close. The voice of the second had a different sound to it, higher, and was further away. The sound of loons calling and Red-tailed hawks screaming are often mentioned as two sounds that epitomize the wild, but I'm starting to think a fox's barking should be right up there too.

The sound sends a chill down my spine. Something about it always sounds urgent, like a frantic alarm call, even though I tell myself it's just their normal communication. It doesn't feel that way to me, though. Standing outside in the dark and hearing the foxes just 50 yards or so away feels as though I am standing in the midst of some invisible danger--not from the foxes, but of something the foxes are reporting to the rest of the forest. They probably consider me the danger, but I share their primal alarm whenever I hear that sound.

Note: In this area trout lily, dog-toothed violets and yellow violets are all names for the same plant. I hear dog-toothed violet most commonly, though trout lily isn't far behind. This confusion is likely why true plant people use the latin names--no confusion when you use those--but I kind of like the different names.