Electronic Green Journal

This aim of this study is to determine if there are differences in tree growth between two sites near Schefferville, Quebec (located at 54°48′N,  66°50′W): the Ephemeral Lake and Airport Woodland site. Tree core samples were collected in order to determine if the “stressed” condition might make a difference in the growth of the trees within the site, and to evaluate how trees may adapt to particular conditions. Cores were collected from 20 trees in the 100x100 meter stressed site, Ephemeral Lake. Core samples were taken from 30 trees located in the in the 10x10 meter ideal site, Airport Woodland.

Analysis of the tree cores showed that that there was no statistically significant difference in rate of trunk circumference (or diameter) growth, but rather, both the stressed and ideal forests displayed nearly identical growth rates. This seems to indicate that trees in both plots had similar amounts of water to facilitate their annual growth rate. However, average tree height and average vertical growth per year are highly statistically significant, and are thus found to be key factors. Trees in the stressed forest grow slower upwards (but not in thickness) than trees in the ideal forest, and they reach lower total height—by a factor of almost two—than trees in the ideal forest.

If we assume, for example, that the stressed forest under study constitutes a random sample of trees that, in a sense, comes from a population of “all stressed forests,” and similarly for the “ideal forest,” then we may conclude that stressed forests—ones exposed to heavy winds and facing unreliable water supply—tend to produce shorter and slower-growing trees than do forests under “ideal” conditions. Equally, the non-significance of the width-growth variable can indicate that it is not necessarily true that tree-width and tree-width-growth-rate are adversely affected by stressed environment.

On the other hand, there were differences in the heights—or lengths of trunks—of trees in the two groups. First, trees in the stressed group were less likely to be growing vertically. About half of the trees in the stressed group were tilted or growing with their main trunk underground. The trees in the ideal group, on the other hand, were nearly all growing vertically, with only a single tree identified as “slanted” rather than “straight.” Also, the trees in the stressed group grew upward at a slower rate than those in the ideal group, and displayed lower overall heights.