Friday, February 5, 2016

Trees


Trees
October 28, 2015
(with a brief update for November 6, 2015)





It was just a few days before Halloween and the end of October. After a long, dry period we had rain in the morning and all of the day before. It was a steady rain but not heavy, and not enough to fill Cottonwood Pond or the Creek. It also wasn't enough to encourage fungi to finally manifest as mushrooms, but the tougher shelf fungi were a little more pliable than they had been in a long time.

 Turkey Tail fungus

Mosses had brightened up, though.




There was a chorus of many birds in the distance (mostly at the far edge between woods and farm field), mingling with the constant, almost electronic-sounding waver of crickets nearby. I could hear a Red-Bellied Woodpecker chattering in the canopy, as well as the chipping of a Cardinal.

The Canopy.



This is the origination of the leaves that had fallen and gathered on the woods floor as well as in the bottom of the bowl of earth I call Cottonwood Pond. There was still a lot of green in the woods, but the canopy was filling with bright, fiery autumn colors. Here is where migrating flocks of birds would be foraging through, collecting insects and larvae from leaves and branches and probing through tree bark. Some year-round and resident birds, such as Carolina Chickadee, Tufted Titmouse, White-Breasted Nuthatch and Brown Creeper, would be doing the same, preparing for winter. This is where the Red-Bellied and other Woodpeckers would be pounding holes in search of insects and calling from the dense crowns of the trees.

Look carefully to see a Red-Bellied Woodpecker against the tree trunk

The Yellow-Bellied Sapsucker would be arriving to spend the winter tapping neat little holes in neat horizontal rows across tree trunks, then taking up the leaking sap with their tongues. This is also where owls would be blending into tree limbs and holes, and where squirrels were skittering from tree to tree across branches, chattering. Their actions would help some autumn leaves loose their hold on twigs, just at the right moment of readiness, and drift down to Cottonwood Pond.

 Cottonwood Pond, as seen from the south

Around Cottonwood Pond, which is in a low area at the bottom of the woods (a creek runs through it), we find the trees that don't mind having their “feet” wet. The soil is always wet here and sometimes even quite water-logged and swampy.

There are, of course, the Cottonwoods. Cottonwood Pond was formed when a huge Eastern Cottonwood tree fell over, leaving a big bowl where the roots had been.That Root Ball is ample evidence that Cottonwood does not need to send its roots far down. The Eastern Cottonwood (Populus deltoides) is always associated with water and is intolerant to shade, so this wet, open bottom area of our woods is perfect for them (I first became familiar with them as a child, when a large one grew at the edge of the woods behind out back yard, in a very wet, swampy area.) They have the fastest rate of growth of any tree native to the U.S. (5-6 feet per year), but are not long survivors. According to Sally Weeks, “recently dead trees with sloughing bark” can be homes for “maternity colonies of Indiana bats.” Maybe I need to observe our fallen Cottonwood Trunk more closely.


Around the fallen Cottonwood are scrappy Boxelder (Acer negundo) saplings with their green stems. Also called Ashleaf Maple, it's the only member of the Maple group with compound leaves. The groups of leaflets resemble those of Poison Ivy. This is another fast-growing, moisture-loving, short-lived tree. One sapling grows next to the fallen trunk at the far end of “little pond.”

Also growing right up against Cottonwood Pond (mostly near the southeast end of the Root Ball) are American Elderberry shrubs (Sambucus nigra.) The clusters of white flowers and dark purple fruits both have great medicinal value as well as food value for wildlife. I can easily find the shrubs in winter because the tan trunks and branches are dotted with raised bumps called lenticels.

In the wet vicinity of Cottonwood Pond stand my favorite native trees, the Sycamores (Platanus occidentalus.) I never tire of seeing their patchwork trunks where bark peels off revealing different colors, looking like camo, then giving way to the shimmering white, majestic trunks rising above.

Sycamore seen in the middle

The fuzzy seed balls stay on the tree all winter, but later I find them, or their loosened, fuzzy seeds, on the ground and on top of the water. Sycamores have the largest diameter trunks of any deciduous trees in North America, so there are some real giants across the country. Their bases often show large, contorted roots scrambling over creek banks where water has eroded the soil and exposed the roots. Giant spaces provide shelter for various water animals.

Willows also love to grow in wet places, but so far in my woods I've only identified the non-native Hybrid Crack Willow (Salix x rubens), or White Crack Willow – at least that's what I think they are. They are short-lived and break easily, so that many of the exist as fallen, splintered logs in my woods. I would love to get the native Black Willow (Salix nigra) started in these woods. It is plentiful in other wet areas of Knox County and really ought to be flourishing near Cottonwood Pond.

Blue Beech (Carpinus caroliniana) does flourish in the bottom area of our woods, very near Cottonwood Pond. The one I call Bent Blue Beech grows at the edge of the pond and reaches over and beyond the Root Ball.


Its main trunk is showing decay and damage, but there are many sprouts growing up from it.


It's a small tree with distinctive bark that gives it another common name, Musclewood, and very hard wood that earned it the common name Ironwood. It is also called American Hornbeam. Nesting songbirds like the Blue Beech's many small limbs, and the seeds are eaten by a number of wildlife. Its yellow autumn leaves turn dark bronze and tend to hang on into winter.




The White Ash (Fraxinus americana) flourishes down there, too. In fact, the Two-Trunk Tree next to the Isthmus is a White Ash, as well as the young tree at the pond's edge near the Barkless Log, and there's a White Ash sapling growing from the top edge of the Root Ball.

Two Sugar Maple leaves cling to the side of the Two-Trunk White Ash tree next to Cottonwood Pond



It's the most common Ash in Indiana and the Midwest, but is heavily threatened these days by the Emerald Ash Borer (though the White Ash trees in my woods seem unaffected, so far.) According to one of my sources, it does not tolerate much wet. The ones around Cottonwood Pond would beg to disagree.

Sugar Maples (Acer saccharum) don't grow so much in the soaked ground, but they do like moist soil, and so they commonly grow in the vicinity of Cottonwood Pond. One sapling grows from the top edge of the Root Ball (a Northern Water Snake was wound around it in May of 2014 – see “A Visit to the Pond with Cherie”) and the mature Sugar Maples nearby send their distinctive “helicopter” seeds down to the surface of Cottonwood Pond and all around. The trees provide dense canopy and shade, blazing fall color, and a dense layer of leaf litter below. The fallen leaves break down quickly.

The bright colors of Sugar Maple trees on the slope near Cottonwood Pond

Hackberry trees (Celtis occientalis) are nearby, preferring the well-drained bottom lands. They are so easy to identify in winter because of their strange, rough, corky, dimpled bark. The dark berries remain on the trees well into winter, providing food to birds, but after falling they are favored by Wild Turkeys, which are occasionally in my woods. The leaves are often riddled with “nipple galls”, caused by a mite, but do not harm the tree.




Trees on the slopes, ridge-tops and edge of our woods create more canopy, more shade, more wildlife food, and more leaf litter. Leaves from all of them drift over and down to Cottonwood Pond in the autumn, making for a woods floor and pond bottom of varied texture and design. Some of the trees are:

Northern Red Oak (Quercus rubra) – a two-trunk Red Oak up the slop from Cottonwood Pond provides the resting place for the top of the fallen Cottonwood.

White Oak (Quercus alba) – some of the largest, oldest trees in my woods.

Leaves of Oak trees turning red in the canopy

Tulip Poplar/Tuliptree/Yellow Poplar (Liriodendron tulipifera) – tall, straight, handsome trees with colorful, tullip-shaped flowers. I find the seed “cones” and scattered, individual seeds all over the woods floor, on the pond water, on the pond bottom and on top of logs. They are numerous and persistent. This is the Indiana state tree.

Sassafrass (Sassafras albidum) – with its dark fruit, leaves of three shapes, and distinctively flavored medicine in all part of the tree.

Black Cherry (Prunus serotina) – with its dark, scaly bark that, in our woods, seems a favorite of Pileated Woodpeckers and Yellow-Bellied Sapsuckers.

Persimmon (Diospyros virginiana) – with succulent fruits enjoyed by wildlife (I often find little piles of seeds on fallen logs, or in animal scat.)

Slippery Elm (Ulmus rubra) – with its slanted-based, rough leaves.

Bitternut Hickory (Carya cordiformis) – I often wonder what wildlife actually like the nuts of this tree, since I find so many of them scattered an uneaten.

There are others, of course, including Redbud, Paw-paw, Shingle Oak and Black Walnut. Some like the far edges of our woods and don't much affect Cottonwood Pond, directly.



Even the dead trees serve many purposes. Many tiny animal species live in the old bark and wood, helping to break it down (the Very Rotten Log across the Creek and Cottonwood Pond is quickly turning to mush) and some other animals eat those animals.

I often run across soft, rotting wood that has been pawed into, possibly by a skunk, to get to the tiny critters.
Some old wood becomes homes for birds and other animals.




Some dead, dying or broken trees quickly grow new saplings.

The three-pronged Blue Beech sapling growing  from the Root Ball

A broken Sycamore readily grows new saplings

Tree trunks and old logs also support colonies of fungi, moss and lichen, which in turn provide food, and sometimes shelter, to small animals, and places for seeds of other plants to take hold.

Lichen

Moss

Below the canopy is the understory layer of the woods, full of saplings, shrubs and some vines. Small birds flit around in this layer near the pond.


Roots, rootlets and exposed root balls provide shelter and food. Birds land on them and hunt for bugs, tiny animals (micro fauna) create tunnels, and havens are provided for frogs, toads, turtles and others. Fungi, moss and lichen all flourish on them.

Rootlets hanging from the Root Ball over the Cove, with spider webs above

The top side of the Root Ball, which tends to stay wetter and shadier, often sports mushrooms, green plants and many gnats.

Root Ball Top

The bottom, which is more exposed to the sun, tends to grow lichen in pale brushes of blue-green.

Root Ball Bottom over dry Pond, with some of Root Ball Top seen to the left

The woods floor is a dense network of activity, mostly going unnoticed by humans. Tiny spiders scamper over the top. Voles burrow below. Birds such as Eastern Towhees scratch the leaf litter vigorously to find bugs. Barely visible or invisible (to the naked eye) life forms break down the layers of leaves into soil.


Some types of tree leaves decompose faster than others. Under the top layer, holes in and along the edges of leaf blades, created by insects and mites, allow fungi and bacteria to enter the leaf interior. Deeper down, skeletonized leaves are dark and slimy from a coating of microorganisma. Deeper yet, humus is being formed and the leaves are barely recognizable. At the bottom is the soil, the “repository for atoms of decomposed plants and animals.” Strands of fungal mycelium and mycorrhizal fungi lace through rotten leaves and wood. The cycle, the process from trees to soil, is complex, constant, and utterly fascinating. Through this, the varied leaves of the mighty trees become the basic, life-giving soil layer that feeds the same trees.

One of my plans this year is to make a Berlese Funnel that I can use to find out what creatures are inhabiting the soil and leaf litter around Cottonwood Pond.

In studying more about the forest floor, I wondered what effect the extended dry period might be having. This would also apply to the pond bottom, where leaves had been falling on a dry surface. I learned from  the book Eastern Forests (Kricher and Morrison) that,

 “Rainwater contributes both hydrogen and oxygen to the soil ... Hydrogen atoms...  replace, or exchange, with atoms such as calcium and potassium that are electrostatically attached to particles of clay. The calcium and other minerals removed by rainfall are washed or 'leached' into lower soil layers. As hydrogen accumulates, the soil becomes increasingly acidic … Leaf decomposition … also adds to the acidity of soils. The more acidic a soil is, the more slowly decomposition will occur, since acidity retards both the growth and activity of microorganisms.”


Normally, we have some healthy rainfall during autumn.  If more acidic soil results in slower decomposition, then how did our dry period affect the soil acidity and decomposition in and around Cottonwood Pond, if at all? Or did the amount of rainfall earlier in the year and the length of the dry period even out, anyway? Certainly, I see slower decomposition on the top layer of leaves when things are dry, but what about in the lower leaf litter layers, and in the soil?

Another affect of the dry period is that I don't see as many isopods (which breathe via gills), earthworms, slugs, snails and millipedes. Are they just all much further down in the layers, or hidden in damper places elsewhere, or does this affect their population numbers and abilities to survive and reproduce? I could certainly tell that the mushrooms have not been encouraged, either, but there is always hope in their network of mycelium in the soil and under bark.




And, in the bowl of earth that is usually a little pond, how will things be different, as dry leaves fall on a dry surface, to be covered by water at a later date, instead of  falling on the water surface and gradually sinking? Certainly, they will take longer to decompose. The dampness from the rain of this day would make some little difference, but nothing like leaves on and in a body of water.



In that way, the colors, shapes and patterns in leaves of trees surrounding Cottonwood Pond should remain evident a little longer.



 ******************************************************************************

Eastern Forests (Peterson Field Guides); John C. Kricher and Gordon Morrison; Houghton Mifflin Company; 1988.

Native Trees of the Midwest; Sally S. Weeks, Harmon P. Weeks, Jr. and George R. Parker; Purdue University Press; 2012.

Shrubs and Woody Vines of Indiana and the Midwest; Sally S. Weeks and Harmon P. Weeks, Jr.; Purdue University Press; 2012.

101 Trees of Indiana: A Field Guide; Marion T. Jackson; Indiana University Press; 2004.


Update
November 6, 2015


 The canopy was thinning out, mostly in the upper reaches of the trees. There was more advanced color in the trees, but many more leaves had fallen. There was a thick layer of leaves on the forest floor. The Root Ball Bottom was dry, and the Root Ball Top was damp. The Pond bottom was still pretty dry, covered by a thicker layer of dry leaves. No additional rain since October 28.





















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