Geographic Patterns and Stand Variables Influencing Growth and Vigor of Populus tremuloides in the Sierra Nevada (USA)

Table 4

Summary data for aspen trees used for crown ratio analysis, and elevation of sample stands. Vicinity BA, SDI, and composition (in terms of percent conifer BA) of neighbor trees taken from 0.02 ha circular plot centered on each sample aspen (𝑛=707) within sample stands around Lake Tahoe Basin (𝑛=9).

Variable	Mean	s.d.	Min.	Max.
Dbh (cm)	28.47	15.42	10.00	86.50
Height (m)	18.16	7.07	5.30	34.90
Crown height (m)	9.64	5.11	1.10	22.90
Crown ratio	0.48	0.15	0.15	0.89
Vicinity BA (m^2 ha^−1)	57.65	33.12	0.50	199.52
Vicinity SDI	985.98	509.61	15.00	2551.55
Conifer (% by BA)	43.23	32.08	0.00	99.44
Elevation (km)	2.11	0.13	1.90	2.26