174 



The Poplars 



Fig. 130. — Wislizenus' Cottonwood. 



catkins appear in March or 

 April and when in flower 

 are 10 cm. long or less, their 

 scales fringed with filiform 

 lobes; the pistillate flowers 

 are slender-stalked with an 

 ovoid blunt ovary, the stalks 

 becoming i cm. long in 

 fruit or more, and nearly 

 as long as the ovoid-pyrami- 

 dal pointed papillose cap- 

 sule. The wood is very 

 similar to that of Fremont's 

 Cottonwood, but somewhat 

 lighter in weight, its spe- 

 cific gravity being about 0.46. 



10. FREMONT'S COTTONWOOD — Populua Fremontii S. Watson 



Fremont's cottonwood inhabits valleys in California from the upper Sacramento 

 to the southern part of the State, Lower CaUfomia, and into western Nevada. 

 It is often a very large tree, occasionally 35 meters high, with a trunk up to 2 

 meters thick; its branches spread widely and droop at the ends. 



The bark of young trees is light gray and smooth, that of old trunks much 

 thicker, dark brown, and 

 ridged. The young twigs are 

 gray-brown, sometimes finely 

 hairy, becoming orange and 

 smooth. The buds are ovoid, 

 pointed, the terminal ones 

 about I cm. long. The leaves 

 are broadly triangular, ab- 

 ruptly short-pointed, commonly 

 wider than long, coarsely and 

 bluntly toothed, except near the 

 tip, rather thin, 5 to 8 cm. long, 

 the base truncate, or somewhat 

 heart-shaped or kidney-shaped; 

 when unfolding they are finely 



hairy, but at maturity are Fig. 131. — Fremont's Cottonwood, 



usually smooth, bright green 



and somewhat shining on the upper surface; the leaf-stalks are about as long as 

 the blades, slender, and flattened laterally. The tree flowers in February or 



