WILLOWS : THEIR GROWTH, USE, AND IMPORTANCE. 9 



posed grove was practically destroyed, while the other gave promise 



of unimpaired vigor for another 10 or 20 years. 



In young willow plantations cattle, horses, sheep, and hogs eat 



the green shoots with avidity, and much damage may be done during 



the first 10 years of the life of the plantation. After that a small 



amount of browsing is often beneficial, as it clears the main stems 



of watershoots and small branches. Further injury by stock after 



this consists in barking the tree trunks, which hastens decay. The 



effect of grazing on the soil in the plantation is very harmful, and low 



yields and early decline mark the plantation where this practice is 



common. 



FLOODS. 



Willows on the flood plains of streams are more or less subject to 

 injury during periods of high water. This has been noted as especially 

 bad in willow plantations where the crop is pollarded, leaving a 

 trunk from 8 to 10 feet in height. The injury to the trunk from 

 floating debris and ice has resulted in the shortening of life, so that 

 one or even two or three crops grown on a 7-year rotation have been 

 lost. Such injury can be prevented by cropping at the ground and 

 allowing the young vigorous shoots that are removed every few 

 years to receive the blows rather than the stump, on the health of 

 which depends the life of the pollard. 



LIFE HISTORY OF THE BLACK WILLOW. 



COMMERCIAL RANGE. 



Of the native American species the black willow is by far the most 

 important, on account of its wide range and its rapid growth under 

 a variety of soil and moisture conditions. Over the greater part of 

 its range this species is a tree willow and generally of considerable 

 size. As a timber tree the black willow reaches its best develop- 

 ment in the rich alluvial bottom lands of the lower Mississippi River 

 and the lower portions of its tributaries. The quantity of merchant- 

 able black willow is much smaller than that of the cottonwood that 

 formerly grew in this region, but to-day the cottonwood is rapidly 

 disappearing and there is little doubt that there will soon be as much 

 standing black willow as cottonwood between Cairo, 111., and Baton 

 Rouge, La. On the whole, however, it will average much lower in 

 quality. 



Most of the willow stands are found below the 35-foot stage of the 

 river. They often occur above this mark, but are generally old trees 

 and on being cut are replaced by cypress, gum, locust, ash, or other 

 hardwoods. The same holds true for cottonwood to a large extent; 

 the reproduction of old stands is very uncertain and the under story 

 species generally takes the ground. 

 8210°— Bull. 316—15 2 



