TREE GROWTH IN THE NORTH MADISON, CT CEDAR SWAMP

We divided each of the three trees we cut in the North Madison Cedar Swamp into 2-m segments, and returned to the labs with a cookie from each segment. We counted the total number of rings in each cookie to obtain age estimates at different heights for each tree. We also counted the number of rings in the sapwood and in the heartwood of each cookie. We measured the radius of each cookie along two axes, and also measured the proportion of heartwood and sapwood. Finally, we obtained measurements for the last seven years of rings (1990-1996).

Using the data thus obtained, we were able to conclude the following:

1. Ring width measurements and volume increment calculations show that the trees observed seem to have wider rings at the base to a height of 4m and then have narrower rings that increased steadily in width from 6m - 14m at which height the rings become more narrow again. A possible interpretation of this could be that the rings are widest at the base of the live crown and at the base of the tree. Click here for data.

2. Analysis of total annual volume increment per year for each tree shows the general trend that over the last seven years, there has been a general proportional decline in the volume being put on by each tree annually.

3. Analysis of sapwood to heartwood ratios revealed that sapwood thickness remains relatively constant throughout the tree (~10-14 rings). Sapwood thickness remains constant at the base of the tree, increases near the base of the live crown, and decreases near the top of the tree. Click here for data.

4. Comparison of true tree volume with volume calculations using the formulas for a cone and a rotated parabola show that the rotated parabola formula more closely approximates true total tree volume.