400 1200 2000 400 1200 2000 



ELEVATION OF SEED SOURCE (m) 



Figure 2—Elevational dines for four variables at seven geographic 

 locations keyed to figure 1. Brackets quantify Isd (0.2). 



DURATION MESIC HEIGHT 



LEAF LENGTH ADJUSTED XERIC HEIGHT 



Figure 3— Geographic patterns of variation for four variables 

 described by isopleths (contour lines) of equal performance at the 

 mean elevation (1,075 m). The interval between isopleths equals 

 V2[lsd (0.2)]. Isopleths represent positive or negative deviations 

 from the mean value (x) of all populations. 



5 



