iQoS] TILiNSEAU— PLANT SOCIETIES AND EVAPORATION 



223 



an open association. The principal trees (mostly under 7^ in height) 

 are Pinus rigida, Quercus coccineay Q. fftarylandica, Q. prinus, and 



Casta nea deftlata. 



The scattered low growth consists of Pteridium 



aquUimim^ Gaylussacia resinosa, Vaccinium pennsylvanicum, Myrica 

 carolinensis, and Baptisia fmctoria. The vaporimeter was placed in 

 the partial shade of a pine tree, surrounded by a low clump of huckle- 

 berry. Readings were made during the same periods as at Station 3. 



Fig. 6. 

 Station 6. 



simiiar 



aporation, 

 aporation 



June 28-July I 

 • 34-3 



aporation 



41 ■ 6% 



July 1-8 

 103.4" 



X5I-5 

 68.2^ 



Jnly S-14 

 72.3" 



131-5 



Total f t6 days) 

 190.0^*^ 



317 3 



54-9% 



59-5% 



slope is more toward the soutli than at Station 

 a greater evaporation rate, other conditions being 



one 



result 



indicate that in spite of direction of slope, the partial 

 asion of the gravel sKde by vegetation has produced a 40 per cent, 

 auction in the evaporation. 

 Station 5.— Forest on top of moraine directly west of Station i; 



altitude 43^. 



{fig, 5) is composed of Quercus 



Q. velut'ma, Q. alba, Fagus amerkatia, Casianea dentate, BetulajeTiia 

 Hicoria glabra, and Acer rubrum. 



The trees 



