12 



MASS. EXPERIMENT STATION BULLETIN 431 



this develop late in the summer, are reddish brown in color and man>- of the 

 bristles arise from pimple-like swellings, or papillae, which together with the 

 bristles is called papillose-hispid (Figure 10) and gives the leaf a very rough feel. 



The leaf margins of three varieties, Rancocas, Wareham, and Harding, are 

 serrulate or finely saw toothed (Figure 11); those of other varieties are entire. 

 Some varieties have a slightly reflexed margin like Rubel, while others are strongly 

 reflexed like Burlington (Figure 12). One variet\', Concord, has the leaf margins 

 reflexed so much that they are described as rolled. These characters of the leaf 



Left: RUBEL 



Figure 11. Leaf Serrulations. 

 entire Right: RANCOCAS — serrulate 



