Bullard Woods:
Second height density plot
  Robert Leverett
  Jun 06, 2005 09:38 PDT 


   On Sunday John Knuerr and I put in a half-acre plot in Bullard Woods,
a relatively flat stand of woods in western Stockbridge, MA near an old
glacial lake called the Stockbridge Bowl. Our objective was to establish
a height-density graph and see how much time it took in relatively
benign conditions. We spent slightly over two hours measuring 44 trees.
Some trees were determined to break the 100-foot threshold without
requiring lots of effort. Other trees were measured accurately because
they represented the best in the stand.

   A simple summary of our efforts follows:

Bullard Woods Height Profile: 2 hrs

Species     >=100 <100    Total
WA               2        4       6
SBH              2        0       2
WO               3        0       3
NRO              1        0       1
SM                0        1       1
HM               12      19     31

                   20       24     44
Pcts          45.5%  54.5% 100.0%

   The Bullard Woods plot reflects 3 age classes of trees:

   (1) A small remaining population of original-second growth hardwoods
in the age range of 200 years. The original population was red and white
oak, shagbark hickory, and white ash.

   (2) Second growth in the 100-year age range, mostly hemlock. That is
basically the forest that is repopulating much of the plot.

   (3) Younger hemlock from 25 to 75 years.

   Our data was gathered for all trees within the plot of circumference
1 foot or more. Of the 44 stems, 70% are hemlock. However, the area we
sampled is adjacent to an area of very large white pines, fairly large
hemlock, and a scattered of birch and other species. Other areas of
Bullard Woods has a mix including some large, old sugar maple and even a
couple of tuliptrees. The disturbance history of the site is complex and
mostly of human origin.

    Some interesting statistics can be derived from our data.

Cir Range       #>=100 ft in hgt     < 100

>= 7 ft                   13                          0

6 to 6.99 ft               3                          3

<6 ft                        5                        20

    This is a very different kind of height to circumference
distribution than we typically see for MTSF where very slender trees can
easily top 100 feet and frequently do. I am interested in seeing if the
above pattern holds for other areas of Bullard Woods that have low to
zero densities of white pine.

     The largest tree in our plot is a very old white ash that measures
12.3 feet in circumference and 111.3 feet in height. This ash was once
close to 120 feet. The tallest blish tree in the plot is a shagbark
hickory at 115.3 feet by my measurement and 115.5 by John’s from two
different directions. That's very good corroboration. The hickory is
10.1 feet in circumference. As can be determined from the above
distribution, 25 of 44 trees or 57% are under 6 feet in circumference.
This is reflected in the hemlocks.

      John and I will provide more statistics from the plot plus more
general information about Bullard Woods and the labor required to
establish a half-acre plot. For our next plot we’ll add azimuth via my
degree-calibrated tripod with laser level. That and a laser range finder
give us a poor person’s transit for horizontal measurements. We’ve been
fine on vertical measurements using clinometer, rangefinder, and

     John and I did improve on the Rucker Index. The index is shown

Site Rucker Index = 112.9
Species   Hgt
WP       131.3
TT        123.4
WA       119.6
SBH      118.5
WO       115.3
HM        114.6
NRO       111.1
SM        107.9
BC         100.8
BB           86.9
Site Rucker Index = 112.94

   A couple of the trees have lost a little height and new trees have
added. The absolute site limit will be between 114.0 and 115.0.


Robert T. Leverett
Cofounder, Eastern Native Tree Society

RE: Second height density plot   Gary A. Beluzo
  Jun 06, 2005 10:16 PDT 

Bob and John:

Awesome job! Do you have any geocoordinates or I wonder if we should come up
with a standardized FIELD SHEET which has room to sketch relative positions
and labels of trees on some sort of grid? Perhaps on a simple grid data
sheet you could pencil in the approximate location of individual trees and
write in the dendromorphometry. Has anyone in ENTS come up with such a
standardized worksheet?

RE: Second height density plot   Robert Leverett
  Jun 06, 2005 13:09 PDT 


   I've been piddling around with a worksheet format. John and I
discussed a simple method of getting the azimuth of each tree in a plot
using my new tripod that has a level and a scale in degrees. I can sight
on a tree and read the angle much easier than I can read a compass. For
the next plot, we'll try to put it all together. The complete process as
we envision it is to:

   1. Locate the center of the plot and set up the tripod.

   2. Put a small tag on each tree to be measured.

   3. Position one person at the center to do the recording and
directing of one or more measurers to the trees.

   4. As a tree is measured, the tag is removed. The recorder would
measure the distance to the tree and its azimuth and record the species.

   5. The measurer would measure girth and height or height class and
call back the numbers. The measurer would also select the age class.

   6. The measurer could also provide other data such as condition.

   I suspect that collecting all these data elements for a half acre
plot will require between 1.75 and 2.5 hours. Despite the work, plots
established with this amount of data should prove very worthwhile for us
in the long run. We would likely measure all trees above a height
threshold very accurately. For instance, in the Bullard Woods plot, we
measured the tallest trees by employing our usual methodology. That is
how we got the 115.3-foot (115.5 by John's calcs) shagbark hickory
identified as the tallest in our plot.

    I can identify approximate GPS coordinates from a terrain map. We
might come even closer using that new aerial photography system.