98 



THE STUDY OF PLANT COMMUNITIES • Chapter V 



-30 



^WINTER 



-WINTER 



DECIDUOUS EOREST. 

 BOREAL FOREST 



MEAN MONTHLY RAINFALLOnche; 



MEAN MONTHLY RAINFALL(inches) 



'. SUMMER 



WINTER 



SHORT GRASS. 

 TALL GRASS- 



MEAN MONTHLY RAINFALL(inches) 



90- 



80- 



UJ 70- 

 Q_ 



60 



50 



40- 



30- 



20 



SUMMER 



H, 



WINTER 



ALBUQUERQUE. N.M. 



EL PASO, TEXAS 



T 



2.5 



MEAN MONTHLY RAINFALL (Inches) 



Fig. 45. Three sets of composite climographs, which permit comparison 

 of forest, desert, and grassland climates, as well as differences within these 

 general types of vegetation. The fourth set, which shows the similarity of 

 climates at stations in New Mexico and Texas, has been used as support for 

 classifying El Paso grassland as short grass, of which Albuquerque is repre- 

 sentative, and not desert grassland as some have done.— From Smith™ 



When .points of equal vapor pressure deficits are connected by 

 lines on a vegetation map, 125 the zones come nearer to matching 

 the distribution of vegetation tvpes on a regional basis than simi- 

 lar ones based on evaporation. Seeking a single comprehensive 



