TREES AND FORESTY 



91 



em species, Speckled Alder {Alnus iiwana 

 ^\ i lid.) . grow along brooks and about 

 marshes. The twigs of the latter can be 

 distinguished from those of the former by 



their downy appearance and by the large 

 number of light-colored lentic'els which give 

 the name " Speckled " to the species. These 

 alders seldom reach a height of more than 

 twelve to fourtci n feet. 



8. Common Locust (Robinia pseudacacia 

 L.). The recognition of locust twigs pre- 

 sents no difficulty. The twigs are slender, 

 smooth and brown, ridged lengthwise and 

 furnished with pairs of thorns. Between the 

 individual thorns of each pair is a bud almost 

 hidden in the center of a leaf scar: each leaf 

 stem of the locust is hollow at its base and 

 fits over a laid, so that no buds are visible 

 until the leaves have fallen. The bark of the 

 tree is rough and furrowed. 



II. Hickory and Oak: Trees with more 

 or less stout and stiff twigs having alternate 

 buds and dark bark. 



1. Mockernut or White Hickory (Hi- 

 coria alba Britt.). This hickory can be 

 recognized by the large buds which are hard 

 and round with few downy brown scales. 

 The terminal bud is always largest; the 

 lateral buds extend at an angle of 4.3° or 

 more (Fig. (14). The tough twigs are smooth 

 and reddish brown, and have conspicuous 

 white lenticels. The older twigs are dark 

 gray. The mockernut hickory is a large 

 tree with bark showing wavy furrows. 



Shagbark Hickory (Hicoria ovata 

 Britt.) has buds with dark scales. 

 The bark on the trunk "shags" off 

 when old. 



Pignut Hickory (Hicoria glabra 

 Britt.) has twigs that are smooth and 

 greenish brown; they may be some- 

 what angled. 



2. White Oak (Querent alba L.) can 



U 



FIG. 66. OAK BUDS 



Braided in appearance due 

 to the arrangement of the scales, 

 white oak buds are rounded; 

 black oak, pointed. 



