Dendrochronology Project

     The Selection Process

       The selection of specimen trees is somewhat complicated and is also based somewhat on luck. In this case we noted that at one part of the lower trunk the rings have an anomoly in their spacing shown where one or two rings are visible between Dr. Rentch's fingers. Since this growth pattern is probably based on some reaction of the tree to physical damage or to a branching limb, it will not give a good sequence of ring growth. Faults like this, or the presence of rot within the trunk, makes for a bad specimen. However, once we found a more uniform place in the trunk, we did take a core sample. Here the borer is started on its trip into the tree. It is a manual process requiring some strong muscles because these trees are literally "hardwoods." This is Core #1.

     Big, Old Trees

     We mentioned that there are guidelines for selecting a specimen tree. Not all large trees are suitable old specimens. Here we see on the left a well known tree stump which is located in the parking lot of S. J. Morse Company in Capon Bridge. One might assume that this tree would make a good specimen for boring. However, on closer inspection it turns out to be a willow, a particularly fast growing and not necessarily long-lived species. This one happens to be located on a very well watered place, so it has grown quite rapidly and is not nearly as old as it first appears. Also, as is often the case with willows, it has a very convoluted trunk which makes finding a place of consistent rings very unlikely. Also, as a softer wood, the willow deteriorates more rapidly than species such as white or chestnut oak. We decided not to bore this one.

     Dr. Craik's Line

     One usually considers trees along boundary lines as older than surrounding trees. We found one on a steep, rocky hillside in the North River valley on property once owned by Dr. James Craik, surgeon of the Virginia Regiment and personal friend of George Washington. Unfortunately, the trees of Dr. Craik's time do not remain, and this chestnut oak is considerably younger. However, we were able to drill a core and hope it may be in the vicinity of 80-100 years old; this is Core #2. Chestnut and white oak are particularly good to use because they are relatively slow growers particularly since they often grow in less productive soils.Trees on poor soil still show the characteristics of seasonal changes, but pack their rings tighter because they have a harder time getting nutrients. Thus it is easier for our increment borer to reach further back in time. Our incremental borer is about 22 inches long. Core #3 was taken near the river about two hundred yards from here.

       We also took a core from an old oak on a hilltop of this property. It turned out to be rotten in the center so we are not sure how many years of growth we sampled. This is Core #4. We will have to wait until Dr. Rentch gets the samples back in the laboratory and studies them before we know how successful our work on this very hot day was.

Building Log Sections

     We also gave Dr. Rentch three sections of an old log barn that was destroyed by a storm several years ago. The barn was located near North River Mills and was originally granted to Thomas Parker before the French and Indian War. George Washington had surveyed the land for Thomas Parker. To see photos of the dismantling of the barn go to: http://www.historichampshire.org/nrm/building/Baker/recycle.htm.htm

What We Need

     After looking at some of the largest and oldest trees in the county, we learned that we are really looking for special trees. Dr. Rentch has characterised them as follows:

1. "We need trees that have developed in a more or less closed canopy forest. Fence-row trees and yard trees may be very big, but they also may not be very old. Their large size is often simply a reflection of the absence of competition and need for height, as opposed to diameter, growth.

2. "Trees growing on poorer growth sites are probably better candidates than trees growing on good growing sites. The difference between poor and good generally comes down to aspect (south and west versus north and east), slope position (ridge tops versus slope toes), and soils (dry shales versus deep loams in bottomlands). This is especially true if our objective is climate reconstruction. We want trees that are sensitive to small variations in climate (on stressed sites) versus trees that have a good life and only occasionally encounter stress.

3. "As far as species, the oaks are generally longer lived and more durable. Of these, white and chestnut oak are the better candidates than black or northern red, although older chestnut oaks are often hollow. Chinquapin oak, although rare, can also be extremely long lived. On extremely dry or rocky sites (barrens) red cedars are often very long lived even though they are not very large. Dead wood on these sites can often extend the chronology well before living trees. Hemlocks can also be very long-lived, however they usually occur on better sites."

 
 
     In answer to our requests that people help us with finding suitable specimens to analyze, we have had a wonderful collection of samples lent to us by Andy Stump whose family has lived for several generations in the South Branch Valley south of Romney. Andy has collected some samples from old log buildings on the family property and from old trees up on the mountain. There are two particularly interesting samples that show fire damage.
 

A closer look at the various samples supplied by Andy Stump.
Note the fire damaged trees (2 upper left & 2 on right)

     Can You Help Us?

     If you have trees that match this description on your property in Hampshire County and are interested in allowing us to bore them for samples, please let us know. The process does not harm the trees and will contribute greatly to our base of knowledge. The contact information is as follows: