16 



BULLETIN 604, U. S. DEPARTMENT OF AGRICULTURE. 



lets and remain on the tree 

 from 3 to 5 years. The 

 leaves are opposite and 

 four-ranked like those of 

 other species, which are 

 related but are character- 

 ized by their long bases, 

 "which extend from one- 

 eighth to one-half inch 

 along the branch. They 

 are also keeled, and each is 

 provided with a small resin 

 gland, which accounts for 

 the pungent aromatic odor 

 so noticeable when the leaf 

 is bruised. The younger 

 branchlets have the ap- 

 pearance of being jointed, 

 as two pairs of leaves oc- 

 cur together, at right 

 angles to each other, and 

 overlap slightly the four 

 leaves above. 



In the seedling stage in- 

 cense cedar is character- 

 ized by three kinds of 

 leaves (PL III), which 

 serve to distinguish it at 

 once from its common as- 

 sociates. The first to ap- 

 pear are the two seed 

 leaves, which measure from 

 1 to I5 inches long by one- 

 eighth inch broad. These 

 are followed shortly by one 

 or more branches bearing 

 awl - shaped transitional 

 leaves, which grade off 

 eventually into the normal 

 scalelike foliage. On 

 thrifty, fast-growing seed- 

 lings normal leaves are 

 produced the first year. 

 On slower-growing seed- 



FiG. 1. — Relative form of the bole of incense cedar Ji^o-s thev do not apnear 



at various ages. & J "i- 



