Tree Down

The winter just past brought Blue Jay Barrens more than average rainfall and an abnormally high number of windy days.  These conditions brought down several dead trees that were no longer strong enough to support the added weight of waterlogged wood.  This tree on the high ground overlooking the creek has been dead for several years.  When I first spotted its fallen mass from the vantage point of the creek, I felt grateful that it had not fallen into the creek itself.   So many trees fall across my trails each year that I am almost convinced of some botanical consciousness willfully directing the tree’s descent.  This specimen obligingly came to rest in an out of the way location where it could quietly decompose.

When I climbed the bank to view the point of landing, I found that the tree had exhibited another type of odd behavior.  Most falling trees tend to flatten as many small trees as possible.  This tree appeared to have magically lowered itself to the ground and settled around the young trees in its path without causing any damage.  One sapling was cradled in the fork of the downed tree, while others were just fractions of an inch from the dead trunk.  After settling down, the tree broke into pieces that laid themselves flat to the ground, in a perfect position to decompose rapidly and give shelter to salamanders and other rotten log dwelling creatures.

The branches were riddled with woodpecker holes.  Many generations of young birds must have fledged from this tree.

I think the profusion of woodpecker holes aided in the tree’s deconstruction upon impact. 

Fortunately, there’s a newly dead tree just a couple of hundred feet further up the creek.  Woodpeckers looking for their old nesting site only have to move a short way to a suitable replacement.  Many of the prior owner’s land use activities caused damage to the trees from which they could not recover.  Most of the damage was inflicted to the tree’s roots by grazing cattle.  Compaction of the ground and damage to shallow feeder roots does not result in a quick death.  Trees may survive the assault for decades, but in a weakened condition that makes them susceptible to insect damage, disease and other environmental factors.  Eventually, their life force gives out and the trees die.  New trees arise to take the place of these fallen old timers.  Given another hundred years or so, the visible damage to the trees of the Blue Jay Barrens woodland should be much less pronounced and the large trees should show signs of having had an easier early life.

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.

Fall of the Woodpecker Tree

This is how the woodpecker tree appeared in May 2014, the last time it was photographed in an upright position.  The stout Silver Maple managed to remain standing for nine years following its death in 2005.

 

This is that same view as of today.  It’ll be a while before I stop doing a double-take as I pass by the window outside which this large tree trunk once stood.  I had the tree cut short enough, so it wouldn’t reach the house if it fell in that direction.  Fortunately, it went the other direction and landed in a spot where it can be left to continue its slow deterioration.

I had been looking at birds on the feeder just minutes before the tree lost its hold on the vertical and flung itself to the ground.  The impact tremor was felt throughout the house.  The sound was reminiscent of a quarry blast.  I would have thought nine years of decomposition would have softened the trunk up a bit.

The three large branches broke at the point where they forked from the stout base.  The tree has securely brought itself to rest and will not be doing any further shifting of position.

Despite nine years of weathering, the outside wood of both branches and trunk are still remarkably solid.  Even when the tree was alive, the point that branches diverge from the trunk was a weak spot.  It’s natural that the breaks would occur here.

The dead tree has had no shortage of insect residents.  The wood surface is covered with holes created by a variety of wood borers.

There were only a very few locations where insects had obviously concentrated their feeding activities on wood located directly beneath the bark.  The bark remained securely attached for several years following the death of the tree.  I expected to find a lot more signs of insects in this part of the wood.

This cavity, found near the top of the smallest diameter branch, fledged a batch of bluebirds this summer.  I’m glad the tree didn’t come down during nesting season.

Decomposition was more rapid at and below the ground, where fluctuation of temperature and moisture levels was minimized.  Had the trunk followed the same pace, there would probably be just a pile of crumbs here now.

Side roots disappeared long ago.  A small central core was all that kept the dead tree upright.

Loss of its vertical attitude has not dissuaded the woodpeckers from visiting the tree.  They still probe the cracks and crevices, but seem to have abandoned it as a regular feeding station.

Sunflower seeds taken from the feeder are now conveyed to a dead limb on the old apple tree for opening and consumption.  I’ll miss watching the adult birds teach their offspring the knack of placing a sunflower seed in just the right crevice so the husk can be easily removed.  The woodpecker tree may be down, but I’m sure it will still provide plenty of interest for me to observe.

Hollow Log

There are several old hollow logs on the woodland floor at Blue Jay Barrens.  This one is a favorite of mine and I stop to visit every time I pass this way.  The bark has long since fallen away and the log is the perfect height for sitting.  The woods down slope is rather open and this is the perfect vantage point for watching birds work through the tree tops.

This tree just happened to fall across the slope on a perfect contour and acts as a trap to catch debris moving down the hill.  The effect has been very noticeable this year with our alternating pattern of drought and heavy rain.  Heavy downpours tend to move down the slope as a solid sheet of water.  That runoff water easily transports the dry leaves.  Without obstructions such as this log, those leaves might exit the woods entirely.  The photo shows a deep collection of leaves on the right side that were caught as they moved downhill.  Ground is bare on the downhill side of the log.

It seems to me that this hollow log would make a perfect home for some animal.  I always expect something to come running out when I sit down.

The inside seems dry and water tight.  I check each time I come by, but spider webs are about the only animal signs I ever see.

A shot without flash shows what appears to be an exit at the other end of the log.  I love using the digital camera to explore where my head and body won’t fit.

When I walk down that way, there is nothing but tree top.  The tree takes a turn before reaching this collection of limbs, so a hole here wouldn’t line up with the trunk anyhow.

I returned to my original vantage point to more carefully examine the scene.  By zooming in on the light, I’m able to see some detail of what I perceived as the exit.  The illumination seems to be coming from above and creating diffused light among the spider webs.

Use of the flash confirms the presence of the webs and shows a water stain left by the rain.  There must be another hole somewhere along the log.

About 30 feet down the log I found this hole complete with spider web.  The web over the opening was dirty and had obviously been there for some time.  Nothing has been entering the log through this hole.  Apparently this log is not a safe place to be hiding.  I guess any small animal possessing my instincts for safe living quarters would be quickly weeded from the gene pool.

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.