Fallen Trees to Soil

Winter is a wonderful time to assess the condition of a woodland.  While the trees are in a leafless condition, it’s easy to get a quick idea of tree density, species composition, trunk size and general condition.  Viewing a winter woodland reminds me of visiting a home stripped of furniture and fixtures.  The basic foundation is laid bare to be appreciated.  What we see during the winter is the infrastructure upon which the diversity of summer life will depend.

I think the best way to describe the Blue Jay Barrens woodland is to say that it is recovering.  1938 aerial photographs show the area to have been woodland then and it has remained in that condition since.  I doubt that this area avoided the deforestation that resulted from timber harvest to create charcoal for the Iron Furnace industry in the early 1800’s.  Since that initial clearcutting, I suspect that the area has remained woodland, so except for that small break, the influence of a closed canopy environment has been at work here for centuries.  Timber harvests have taken place during the past 150 years, but they have been selective cuts that left much of the canopy in place.  Each harvest took the best timber and left the remaining trees standing.  That long term strategy has left its mark.  Most of the large trees display damage or deformities that would have made them of low value during the last harvest.  Add to that the damage that occurred to tree roots from cattle grazing in the woods and you have a stand of trees that is in far from prime condition.  The woodland as a whole is slowly improving, but recovery is a long process that is still working through some ugly times.

Most of the woodland is located along a series of east-west oriented ridgetops.  The ridgetops are quite narrow and drop off steeply on each side.  This topography is probably what kept the area from being plowed for crop production.  Soil is extremely shallow to bedrock on these ridgetops, which would have also made them unsuitable as cropland.

Part of the woodland recovery process is the loss of trees that were weakened by past abuses.  A few trees have traditionally fallen each year.  This process creates pockets of light that allow younger trees to grow.  The result is a diversity of tree size within the woodland itself.  The 2012 derecho accelerated the process by simultaneously bringing down multiple trees in several different areas.

A common monument to a wind thrown tree is the mass of newly exposed roots.  Healthy trees can survive some awfully strong winds.  The problem is that so many trees suffer from multiple environmental factors.  This particular tree had several trunk deformities as the result damage inflicted early in the tree’s life.  Cattle in the woods would have stressed the tree through soil compaction and physical damage to the roots.  Shallow, droughty soil provided harsh growing conditions throughout the life of the tree.  When you add to that the stresses put on most trees by general air and rainfall quality factors, the result is a tree that is extremely vulnerable to a wide range of hazardous conditions.

The root masses can be quite impressive.  This one measures about seven feet from the ground to the top of the soil ball.  Broken roots project upward another couple of feet.  Typical of most of these trees, there are no particularly large lateral roots present.

As the tree fell, chunks of bedrock were scattered about.  The presence of a solid bedrock layer just below the soil surface prohibited the tree from developing any sort of tap root.  With such a tenuous hold on the earth, it’s surprising that the tree remained upright as long as it did.

The bottom of the root mass mirrors the solid rock layer that blocked all root penetration.

The smaller roots, responsible for drawing water and necessary elements from the soil, were restricted to an inches thick layer above the bedrock.  Annual drought stress would have come early to this tree.

In addition to changing the composition of the woodland overstory, fallen trees modify and diversify the woodland floor.  The root mass will eventually decompose through a series of roughly predictable stages.  During the first few years, soil particles will detach from the roots and drop down to form a mound.  Next, the smaller roots will begin to decompose.  This material, along with small rocks, will be deposited on top of the soil mound.  The larger roots and stump will be the last to decompose.  As this material breaks down, the large rocks will be released to take their place atop the soil mound.  Decades from now, an area of slightly deeper soil beneath a mound of loose rock will provide an interesting microhabitat for plants and animals.  It might also cause some people to wonder how that pile of rock came into existence.

Another habitat changer is the tree trunk itself.  Like the tree stump, the trunk will eventually decompose and disappear from sight.  What it will leave behind is a strip of slightly deeper soil with an organic matter content that will allow it to hold slightly more moisture than the surrounding area.  These soil conditions would most likely support a greater concentration of plant growth and produce a noticeable swath of plant life across the future woodland floor.

Prior to my arrival on the property, the fallen trees were regularly cut and used as firewood.  As a result, I have few old logs that have had time to completely disappear.  I do have many that have come a long way on their return journey to the soil.

Subtle differences in available moisture, soil depth, soil composition, sunlight exposure, temperature and other environmental factors create a diversity of micro habitats that allow for a diversity of plant and animal life in a given area.  Each tree that falls and processes back into the soil, increases that diversity and that matches well with my property management goals.

When I see a fallen tree, I often contemplate what that will mean to the health of the woodland environment 50 or 100 years from now, but I don’t forget the immediate changes that occur.  A downed tree, whether or not it has actually completed its journey to the ground, provides an instant source of food and shelter to animals and plants that could not have utilized that resource while in its vertical position. 

The woodland at Blue Jay Barrens is certainly an odd looking creation.  I won’t be around to see this woodland graduated from its recovering status to that of healthy, but I’m confident that it is moving in that direction.

The Future Forest

The trees that will one day fill the newly created woodland opening are already in place as seedlings and small plants crowding the forest floor.  Growing in the perpetual shade of a closed canopy has kept the trees in a diminutive condition for many years.  Though small, they are perfectly healthy trees and will take advantage of the sun’s energy to begin a period of rapid growth.  It will now be a race to see which trees will claim a permanent position in the new section of forest.

The most abundant seedling is that of the Sugar Maple.  Sugar Maples have a dominant place in the forest community here and their seeds easily germinate.  Quick to take advantage of a bit of sunlight, Sugar Maples are an early favorite to win the race for dominance.

Mature Ash are less common than Sugar Maple, but their seedlings are just as numerous.  This is also a fast growing tree and will shoot up as quickly as the maples.  These could easily be the only two species to grow to maturity in the new opening.  Slower growing species might survive, but their growth will stop once they are topped by the faster growing species.  In order to end up with a mix typical of the surrounding forest, it is often necessary to cut some of the Ash and Maples away from the slow growers.  It’ll be several years before I have to make any decision on that type of action.

I found a single Red Mulberry in the exposed ground cover of the opening.  So far, there haven’t been any mature Mulberries discovered at Blue Jay Barrens.

Blackjack Oak is more often found in fields and fence rows outside the mature woodland.  This is a species highly favored by the Edwards’ Hairstreak butterfly larvae, but the ants associated with that larva are not found in the woods.  My management decision would be to suppress this oak in favor of another species from the Red Oak group.

Several species are present from the White Oak group.  It would be nice to have two or three of these survive to become canopy trees.  Historically, the forests of this area were composed of mixed species.  That’s what I would like to see fill this opening.

Hickories are also standing by to enter the race.  Hickories and Oaks produce large, heavy seeds that support an amazing number of mammal and bird species.  The seeds are of a different type and arrive at a different time than those of maples and ash.  The presence of both types of trees in the mix allows for a healthy and varied mix of woodland creatures.

On the far side of the clearing are young trees that grew up in response to earlier openings in the canopy.  Most of those young trees are Sugar Maple and they grow so closely together that it’s difficult to walk through that area.  This clearing will look like that in another 20 years, but I hope the species mix will be a little more varied.

A New Woodland Clearing

I finished my survey of the woods and found another area that suffered several broken trees as a result of the wind storm that came through at the end of June.  In this case, about a dozen neighboring trees all went down together to create a sizable opening.

A huge void is now present in what was just recently a closed canopy. 

Because of heavy cattle usage long ago, this section of woods was almost park-like in its absence of shrubs and mid-level trees.  The lack of damage to the surrounding trees makes me think that a violent down draft occurred along with the straight line winds.

As with the other damage site, these trees were broken off rather than uprooted.

All of the downed trees had already been weakened by damage and defects inside the tree.  Trees in previously grazed woodland may grow for decades after the removal of the livestock, but they never recover from the damage that was done.  Eventually the weakened tree will fall to some unexpected event.

The trees all fell in the same general direction and the tops hit ground outside the newly formed clearing.  That has created quite a long row of tangled branches.

A few trees broke high on the trunk.  This area is going to be a wonderland of dead wood.  The Pileated Woodpeckers will be worn out trying to tear apart all of those dead logs and stumps.

This oak and maple have made an interesting tangle.  I believe the oak broke first and leaned over onto a larger tree.  As the maple fell, it caught the oak mid-trunk and drove it to the ground.  The oak top, hopelessly tangled in the large tree, remained in an upright position causing the trunk to suffer a second break.

It will take years for these logs to reach their final resting place on the ground.  As the smaller branches weaken from decomposition they will break and allow the trunk to shift or fall into a new temporary resting place.  There’s still plenty of danger here to the unwary person who inadvertently puts himself in the way of a shifting tree trunk.

There’s still about 40 feet of the oak tree being held vertically.  That will eventually fall and could still do a lot of damage if a hapless person were to be caught beneath.

That gaping hole in the canopy will let in a lot of sunlight.  That will not just change the look of the clearing.  All of the surrounding open woodland is going to have a sudden wealth of sunlight and a corresponding surge of understory growth.  It will be interesting to see how things progress.

The Woods

I don’t think I spend enough time in the woods. I visit often enough to know that things have changed considerably in the last 25 years. Deer and Turkey, uncommon when I first moved here, have increased in numbers to the point that they are a major factor in the future development of this woodland ecosystem. I’ve just not properly documented the changes that have occurred.

The prairies have always taken priority. The prairies are where most of the rare and unusual vegetation is to be found and that’s where I’ve spent most of the free time I’ve had available for management activities. The woods has been more of an attractive backdrop to the prairies and a shady place to sit and relax during the summer. It’s just been in the last few years that I’ve found time to look more closely to the workings of this woodland.

Woodland management activities have so far centered around the removal of invasive plant species. Luckily, most of the woods is free of invasives. The invasives are concentrated on the lower slopes and in the valleys. I wonder if the ridgetop soils provide an environment too hostile for colonization by invasives. These soils hold very little water and are dusty dry right down to the bedrock during late summer and early fall. I’m really curious about the effects of this dryness on soil organisms and the cycle of changes that occur over a typical year.

I always have time to admire the odd shaped trees. Of course, that describes most of the trees at Blue Jay Barrens. This tree has a history of being a den tree. About five years ago it sheltered a family of Gray Foxes and before that it was Raccoons. The cavity has enlarged considerably since then and is probably too spacious for these species to find comfortable. Maybe I’ll look in one day and find a bear.

The past couple of years have been excessively windy and several trees have suffered broken tops and branches. This branch received a twist that created a split lengthwise down its center. This isn’t the type of wound that heals itself.

The worst part is that the branch is still hanging up in the trees. Eventually it will die and fall. It’s things like this that keep me looking up when I walk through the woods. I’ve stopped on occasion to examine an odd looking tree in the woods, only to find that it was actually a broken branch that had fallen and speared the ground with such force that it remained solid and upright. I certainly don’t want to be in the way when a big branch decides it’s time to head for the forest floor.

Winter Brown and Gray

The Blue Jay Barrens landscape has taken on what I think of as its winter appearance. With the exception of the evergreen species, the colors have become dominated by browns and grays. Even so, there’s still a brightness and freshness about all of the plants.

The grasses and forbs are still standing upright and all display a strength that makes you believe they could stand forever. Four months of rain, snow, wind and animals will certainly change the look. In late March I’ve seen this field look as though the circus had just packed up and left. The type of winter weather we experience this year will determine the look of the field.

Leaf fall and my clearing efforts now make it possible to view the series of prairie patches. Light brown for prairies and grays for the trees. Eventually, I’ll reach the point where the prairies are connected by a series of open passages.

In a year of normal rainfall, all of the cedars would be bright green at this point. Varying degrees of drought stress has left them ranging in color from green to yellow to brown. Position on the landscape has greatly influenced the amount of rainfall available to the tree and the resulting color change. The brown tree near the center of the photo sits directly atop a watershed break and had the least amount of available moisture in the line.

Viewing a block of cedars shows the same variation in colors among the stand. The resulting color pattern is partly due to individual tree genetics, but the microclimate at the site of each tree has had the most effect.

We’ve had nearly five inches of rain during the last two weeks, so soil moisture is much improved. The water won’t do much to improve the cedar color unless the temperatures are high enough to allow for photosynthetic activity. Cedars typically lose some of their green color during the winter, so the already off color trees could really look afflicted if we have an extremely cold winter.

Rain and winds have stripped most of the oak leaves from the trees. Oaks often retain their leaves long into the winter which makes the woods seem more substantial. Things just seem to be too open and exposed for early December. I just get the feeling that I’m going to be looking at the browns and grays for an awfully long time.

Animals in the Woods

I was looking forward to a sunny walk in the woods yesterday, but despite a forecast for a sun filled afternoon, the clouds remained and it was definitely gloomy. It was unusually quiet in the woods. For the most part, when I wasn’t moving around crunching dried leaves, there wasn’t a sound to be heard.

When something did move, it was very easy to detect. From the ridge top I could hear something walking across the slope of the hill. A Coyote was hurrying by. It’s a shame there wasn’t an opening large enough to capture the entire Coyote, but I was just happy to get one half way focused shot before he hurried on. I rarely see Coyotes and when I do, they’re not waiting around to have their pictures taken. A family group of Coyotes can claim a territory of 6 to 10 square miles, so it’s uncommon for them to be traveling through Blue Jay Barrens at the same time as myself.

As I crossed over into the next valley, I could hear something really scratching away at the leaves. This Whitetail buck was not trying at all to be stealthy. He kept looking around, but never did seem to notice me.

I think he was more interested in the buck on the other hillside. This one was on the move and never slowed as it ran over the ridge and away.

Here’s what the first buck was up to. He was busy marking his territory with this scrape. Between the deer and the turkeys there’s not going to any part of the woods that’s not torn up.

When I returned to the house, I went out to get the mail and saw this little dog going down the road. He’s a stray that’s been at my neighbor’s house for a little over a week. He must not be looking for a new home, because he just hurried away when he saw me. I know he’s not in the woods, but I felt I just needed one more animal to round things out. I’m sure he’s available for adoption if you want him.