GLAUCOUS WILLOW 



GLAUCOUS WILLOW. PUSSY WILLOW 



S&lix discolor. 



A small tree rarely more than twenty feet in height, more often a 

 shrub. 



Bark. Light greenish brown sometimes tinged with red, scaly. 

 Branchlets at first are stout, dark reddish purple, coated with pale 

 pubescence, later dull green. Buds are dark reddish purple, flat- 

 tened, acute, three-eighths of an inch long. 



Leaves. Come out of the bud convolute, are oblong or oblong- 

 ovate or lanceolate, gradually narrowed at both ends, wedge-shaped 

 or rounded at base, crenately-serrate, acute. When full grown are 

 thick and firm, smooth, bright green above, glaucous or silvery white 

 below, from three to five inches long, from an inch to an inch and a 

 half wide. Midribs are broad, yellow ; petioles slender ; stipules 

 leaflike, semilunate, acute, dentate, about one-fourth of an inch 

 long, deciduous. 



Flowers. Catkins appear in very early spring, before the leaves, 

 over an inch long, two-thirds of an inch thick, white and silky be- 

 fore the flowers open. Stamens two with long slender filaments. 

 Ovary is elongated, downy, long-stalked and crowned with a short 

 style and broad spreading stigmas. 



Fruit. Capsule, cylindrical, long pointed, pale brown and downy. 



This willow is common along the banks of streams and 

 ranges from Nova Scotia to Manitoba and south to Dela- 

 ware ; west to Indiana and Illinois and northwestern Mis- 

 souri. 



The leaves and twigs of many willows are subject to gall 

 growths caused by the stings of insects. The great cone-like 

 buds, an inch or more long and three-fourths of an inch in 

 diameter which are found at the tips of the branches of Salix 

 discolor especially, are an interesting example of these. One 

 often sees a Pussy Willow, growing by or fairly in the bed of 

 a small stream, virtually covered with these monstrous buds. 

 But open one of them with a sharp knife and within will be 

 found the sleeping larva of a gall-fly. This bud is formed of 

 many overlapping scales which are crowded and modified 

 leaves, all diverted from their normal purpose and com- 

 pelled to serve as the covering of an enemy. 



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