Monday, January 26, 2015

Fishing Spider

I use this flat rock to monitor the progress of breeding Streamside Salamanders.  This section of the upper reaches of the creek typically has a moderate flow of clean water through the winter and spring seasons.  The salamanders visit here in good numbers and have used the underside of this rock for the past several years as a repository for their eggs.  The rock is not embedded in the stream gravel and is easy to lift for a peek beneath.  No salamanders were found during my last check beneath the rock.  Instead, as I tipped the rock up on its side, a large spider fell from beneath and began floating away in the current.

I quickly scooped the creature out of the water and found it to be a female Fishing Spider, Dolomedes vittatus.  This species is found near small, running streams and is covered by water repellent hairs that allow them to walk on the water’s surface.  They can also submerge, with the hairs maintaining a surface film of air around their bodies.  I couldn’t tell if this individual had actually been utilizing an air pocket beneath the rock or if it was just utilizing the film of air covering its body.  The bottom of the rock is smooth and fully submerged, so if an air pocket was present, it would have to be small.  Using the warmth of the water is a neat way to survive subfreezing temperatures.  Even at its coldest, the temperature of flowing water in the creek doesn’t drop below 32 degrees F.  When nighttime temperatures hover near zero, taking advantage of the warmer water temperature is a distinct advantage.  The surface of the air film covering the spider would also allow for oxygen and carbon dioxide exchange with the flowing water.

The spider was cold and its first movements caused it to roll down into my hand.  As the spider gained warmth from my hand, its movements became more coordinated.  It wasn’t long before it wouldn’t hold still for more photos.  I released it into a cavity beneath a large rock that set half in and half out of the water.  I figured the spider could choose whether or not to return to a submerged resting spot.

Talking about spider size can sometimes be confusing.  This is considered to be a large spider for this area.  If I described it by using the common measure of body length, I would say that it was just a little over half an inch in size.  That might seem small to many people.  If I used the length from the tip of one leg, on through the body and out to the tip of the opposite leg, this spider would be described as 3½ inches across.  Some might use those dimensions to describe it as palm sized.  Either way, it makes it sound like one big spider, but most of that size is just open space between the legs.

This is an attractive species.  The two dark markings near the center of the carapace and the rows of white spots along the abdomen are diagnostic.  Notice that this individual is missing one of its hind legs. 

Good eyesight is a must for these hunting spiders.  A row of four small eyes sits below a row of four larger, more widely spaced eyes.  This lady shouldn’t have any trouble keeping track of her prey.

From the front, the markings of the spider seem to form a face.  The abdomen is decorated with two dark spots with white edging that look like eyes.  The twin dark markings on the carapace suggest a nose and the curved rows of eyes designate the mouth.  I don’t know that this configuration of characters actually serves any defensive functions, but it’s still interesting.  The shape and markings of the abdomen as seen from this angle remind me of the 1978 version IL series Cylon.  By your command.

Friday, January 23, 2015

Osage-orange

This is the fallen fruit of the Osage-orange, a tree commonly found in old fence rows.  When I see this fruit, I always think of Mammoths and Ground Sloths, two members of the megafauna that used to roam this area until their extinction nearly 10,000 years ago.  These large herbivores were the last species to utilize the fruit as a food source and were the primary dispersal mechanism for the seeds.

Osage-orange produces an abundance of seed inside the fleshy fruits.  The large herbivores would eat these fruits whole and pass most of the seeds undamaged through their digestive systems.  The animals would then wander around dropping the seeds with their dung.  In this way, the trees were spread across the landscape.

A few modern mammals are attracted by Osage-orange fruits, but it’s not really the fruit they are after.  Most of these animals, such as squirrels, are seed predators that actually open and eat the seeds.  Empty seed coats are all that remain of seeds that will have no chance of being dispersed.

The actual flesh of the fruit is left behind to decompose.

At the time of European colonization, Osage-orange was only found in the Red River Watershed region of eastern Texas.  The trees found here today were introduced and are not considered native to this area.  Since the tree was spread so easily by large prehistoric herbivores, I wonder if Osage-orange might have had a much broader range during the Pleistocene when the megafauna were so common and widespread.  I haven’t read anything that suggests such an idea, but I think it’s a possibility.  Osage-orange may have actually grown on this spot in the far distant past.

Osage-orange was commonly planted as a living fence.  Its tight growth, along with the presence of some strong thorns, helped to keep livestock contained within the field.

Their habit of spreading limbs far out into the field, caused Osage-orange to be removed by many farmers who didn’t want to be raked from their tractor seat by the thorny branches.  There are only a few of these trees growing at Blue Jay Barrens.  Most show signs of having been cut at some time in the past, most likely for use as fence posts.  Despite the fact that the seeds are viable and easily germinated, the trees are not spreading into the fields, so they don’t currently fall into the invasive category.  For now, I’ll leave the trees alone and keep imagining that a herd of Mammoths has gathered around the tree to eat fruit.

Wednesday, January 21, 2015

Cedar Maintenance in the Middle Field

The marking flags are once again flying in the field as I resume my cedar maintenance activities. 

I’m working in what I think of as the Middle Field.  The field seen through the trees is the Far Field, which runs up against the County road.  In the other direction is the Near Field, which sits beside the house.  Between those two fields is the Middle Field.  It makes sense as long as you don’t consider all of the fields that are in other directions from the house.

The Middle Field is a narrow, wedge shaped field that points to the north.  Even though it is only two acres in size, the Middle Field contains a variety of diverse habitats.  Along the east side is a shallow valley containing a small, intermittent stream.  A narrow strip of deep soil along the stream bank encourages tree growth.

Just a short climb up the slope brings you onto shallower soil where the prairie vegetation dominates.

The areas of open grassland reach as narrow fingers among the tall cedars.  In these areas I don’t need the help of flags to guide my search for little cedars


At the top of the slope is a small thicket of Virginia Pine.  It’s not hard to pick out the tree that was most likely the original colonist.  The rest of the stand probably originated from that single individual.

Just through the pines, the field opens up onto a level hill top.  As the old fence row is cleared, this part of the field will become more associated with the Near Field seen through the trees to the left.

A thriving stand of Dwarf Sumac is found on the hill top.  We’ve had nearly no snow so far this winter, so the Sumac fruits have not been touched by the birds.  The sumac fruits seem to be eaten only out of necessity.  It’s only during the harshest of winters that this fruit seems to disappear.

The pointy end of the Middle Field has already been mowed.  If weather permits, I’ll mow the rest of the field following the cedar maintenance activities.

I’ll be removing Eastern Red Cedar as well as Virginia Pine seedlings from this field. 

Virginia Pines produce an abundance of seeds.  Those seeds seem ready to germinate as soon as they hit the ground, so pine seedlings are especially abundant near the mature pines.  Fortunately, if cut off at ground level, the pines will not regrow.

Because the field was mowed just three years ago, the young cedars are not very tall.  I generally like to conduct cedar maintenance activities in a field prior to mowing.  Sometimes circumstances conspire to limit the amount of time available for field work and I must decide which would be the most beneficial activity to pursue.  Three years ago, I decided to limit the threat of cedar competition on the prairie plants by going ahead and mowing the field.

As a result of that earlier decision, I am now cutting cedars that have regrown from a cut stem.  These individuals form a dense top growth, but still have only a single stem needing cut.

The mower actually caused the stem of this cedar to split three years ago.  Live branches, safe beneath the cut, responded to the loss of the tree top by generating some rapid growth.  The loss of a dominant top stem allowed the side shoots to grow uncontrolled in an attempt to replace that dominant leader.  As long as there is the least bit of green growth left, a cut cedar will successfully regrow.


My activities don’t go unnoticed by the local residents hiding behind an old brush pile.  They usually don’t seem too interested in my cedar maintenance activities.  It’s the mowing that they really get excited about.  They can’t resist checking out the interesting odors generated by freshly cut vegetation.

Friday, January 16, 2015

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.

Wednesday, January 14, 2015

Potato Dandelion Transplants

I was in the woods yesterday and decided to go by and check on the Potato Dandelion, Krigia dandelion, tubers that I transplanted last August.  At least a few of the tubers survived and have developed clusters of leaves.

Cold weather causes the leaves to blush a bright lavender.  When temperatures begin to moderate, green blotches will develop that give the leaves a pattern similar to early Trout Lily leaves.  I think this coloration causes the plants to be overlooked by the casual observer.

I planted over 50 tubers along this ridgetop, but only found a small number of plants yesterday.  The bare ground chosen to receive the tubers in August has since been covered by fallen leaves.  By late April the Krigia plants will have developed enough for the leaves to be easily seen above the forest leaf litter.

In addition to planting tubers in the woods, I introduced a few into a new container.  These plants are growing in a 22 inch diameter container that had been filled with recycled potting soil.  First growth appeared in late September.  Growth was rapid until the sub-freezing weather arrived.

Leaves show signs of stress from exposure to cold, dry air.  Each warm spell allows the plant to increase the size of the youngest leaves emerging from the center of the rosette.

This is the seven inch diameter pot that housed the stray Potato Dandelions found growing in the burned shed site last April.  After sifting out the large tubers last August, I returned the soil to the pot.  There were enough small tubers left in the soil to produce this growth.

A few drops of water, left by the rain a few days ago, remain frozen on the leaves.  I’ve seen these plants receive much worse damage than this and still recover with the return of warm weather.  So much about this species suggests that it should thrive in this area, but it still remains a rarity in Ohio.

This 18 inch diameter container has been producing Potato Dandelions for many years.  Somehow, this pot has become contaminated with Chickweed.  After harvesting the tubers in August, I’ll add a couple inches of fresh soil to this container.  That should reduce the possibility of Chickweed next year.

Leaf damage is not quite as bad in this container, even though there are still ice crystals sitting on the leaves.

Most of the plants show minimal damage.  All three pots are situated in different locations and this pot was in a position that allowed snow blowing from the barn roof to cover most of the plants.  The snow protected the leaves from the dry air, which seems to be the major cause of leaf damage.  I hope to have an abundance of tubers for transplanting next summer.  Given time, I should be able to find other suitable locations in which this plant can thrive at Blue Jay Barrens.