4 JOl'RNAl, OF F()K1';STKV 



The field measurements were made al stations representative of 

 different conditions of composition and height growth, usually at 

 intervals along profile trips over ridges from cove to crest, or on trips 

 confined to coves or ridges. At each station determinations were 

 made of the age and height of healthy representative dominant trees 

 of the important timber species, both "immature" and "mature" (as to 

 height growth). Chestnut and other intolerant species previously 

 mentioned were the principal subjects of measurement, but old and 

 even young trees of more tolerant species, such as white and chestnut 

 oaks, hickories, black gum, pines, hemlock, etc., were commonly meas- 

 ured for comparison with chestnut. The average height of "mature" 

 trees which have practically ceased their height growth was considered 

 a sufficiently good indicator of the quality of site, at least for the broad 

 limits which were considered suitable for practical purposes. Every 

 chance to secure height growth data on young dominant trees of 

 various species, however, was utilized and in many cases sectional age 

 counts were made at several points on the stem. The results of the 

 field work were finally compiled in 35 "trips" representing conditions 

 on and near four National Forests,* and comprising a total of 145 

 stations, 419 sample tree measurements '(many of them growth analy- 

 ses), and 31 sample plots. 



CLASSIFICATION OP THE; DATA BY MEANS Of HEIGHT — AGE CURVES 



To identify a site in terms of any age class on an area, a set of 

 height growth curves was indicated. Each site would then be repre- 

 sented by a curve of the height growth, in terms either of an "average" 

 site classification considering all species dominant in the crown cover, 

 or of a "standard" classification for a particular species or group of 

 species, in accordance with Roth's plan. In compiling the field notes, 

 the "standard" plan in terms of chestnut was first tried. The heights 

 of all the dominant chestnut trees measured were plotted on the basis 

 of age, limiting curves were drawn, and the points were segregated 

 by interior curves into three equal height classes designated, from 

 best to poorest, as "Sites I, II, and III." This constituted a "standard" 

 system for chestnut alone. The "average" plan then suggested itself, 

 and the heights of all the dominants of every species measured at the 

 same stations at which the chestnut measurements were taken, together 



*The White Top (Virginia and Tennessee), Pisgah (North CaroUna), 

 Georgia (Northern Georgia), and Monongahela (West Virginia). 



