36S 



BOTANICAL GAZETTE 



[may 



a record of 9.9 cc; the beechwood n.2icc; the short-leaved 

 pines 11.67 cc; the long-leaved pines on 



Norfolk 



order 



essentially that in which the successional changes as observed occur, 

 from the xerophytic pines and oaks through the xeromesophytic 



forest (fig. o). The beech wood, it 



pines and oaks to the climax forest (fig. 9). 



must be noted, was subject to pasturing and gave evidence of 



Fig. 9. 



evaporation 



in (1) mesophytic climax forest; (2) flatwoods; (3) Spanish oak-post oak-hickory 

 forest; (4) short-leaved pine forest; (5) pastured beech forest; (6) scrub oak forest; 

 (7) long-leaved pine forest. 



recent burning (probably to promote pasturage), being quite free 

 of undergrowth. Cattle and hogs grazed through this forest and 

 Erechtites hieracifolia Raf . appeared among the herbs. 



On the basis, however, of the average rate of evaporation esti- 



mated for the year, the order is changed. The Spanish oak-post 

 oak association has an evaporation rate very close to that of the 

 short-leaved pines, being 14 .00 cc. daily for the former and 14.22 cc 

 for the latter. Both of these stations were observed without a 

 break from September 191 2 to May 17, 1914, and their averages 

 taken accordingly. The two stations are alike in that each has 









