THE TREE AND ITS FORMS. 



15 



The bark varies greatly and has no single easily distinguishable 

 characteristic common to the genus. The reddish-brown bark of 

 the shagbark scales off in long thin strips, and is so characteristic 

 that it can not be mistaken. (See frontispiece.) The bark of the 

 moekernut is light gray and does not scale off at all. Between 

 these two extremes, there are all degrees of scaliness, and within 

 each species the bark varies so that it alone is not a safe guide in 

 distinguishing the species. 



The bud characters divide the hickories into two distinct groups 

 the true hickories and the pecan hickories. The true hickories are 

 characterized by full, 

 round buds, with many 

 overlapping scales, of 

 which the inner ones are 

 usually hairy. Buds of 

 the pecans are generally 

 thin and narrow and 

 have no overlapping 

 scales, but are covered 

 by two closely fitting 

 ones with a glandular 

 surface. This natural 

 distinction is further 

 borne out by other 

 general characteristics 

 of the two groups. 

 The nuts of the pecan 

 group are generally 

 thin-shelled and thin- 

 husked, the leaves have 

 from 7 to 15 compara- 

 tively narrow leaflets, 



the bark is Only mod- FlG> 2- ~ Water hickory (Htcoria aquattca). Twig, natural size; 



leaf and fruit, one-third natural size. 



erately scaly, and the 



wood is comparatively weak and brash. In the true hickories, the 

 nuts are generally hard-shelled and thick-husked, the leaves have 

 from 3 to 9 leaflets, the bark is generally scaly, and the wood is 

 strong, hard, and tough. This group furnishes practically all the 

 hickory wood of commerce. 



There is still much difference of opinion among botanists as to 

 the number of species. Some botanists distinguish as many as 15. 

 From the forester's standpoint, however, the extremely minute sub- 

 division into species is unnecessary and confusing. The newly dis- 

 tinguished species closely resemble in some characters the older types, 

 so that it is difficult for even trained botanists to tell them apart. 



