13 



larger trees, but since it makes its appearance late in the season it is 

 seldom serious. 



WHITE WILLOW. 



White willow has about the same light and moisture requirements 

 as cottonwood, to which it is closely related. It also is a river-bottom 

 tree, but, unlike cottonwood, it is capable of forming and maintain- 

 ing an exceptionally dense stand. When planted close together the 

 trees put on an excedingly rapid height growth, and form tall slender 

 stems, well cleared of branches. In natural pruning white willow is 

 perfect. The branches are brittle at the base, and are often shed in 

 such quantity that they accumulate between the rows and may be 

 gathered for kindling. 



It makes better fuel than cottonwood. It is easily split, and when 

 well seasoned makes a fence post which will last about six years. For 

 a dense windbreak it is surpassed only by the evergreens. All in all, 

 it is a desirable tree to plant in moist situations, and especially in 

 the sandy, porous soils of the river valleys. It can be planted pure 

 or in mixture with cottonwood. Cuttings are generally used as the 

 planting material for both species. 



A single row of willows often brings good results, both for low, 

 dense windbreaks and for fuel and posts. This tree is practically 

 free from frost cracks. The foliage remains green in fall, even 

 after frosts occur, a proof of its hardiness. Caterpillars occasionally 

 defoliate the trees. If they come early in the season and their pres- 

 ence is considered serious a spray may be used. Sheep and hogs 

 devour the leaves and twigs greedily. They keep a forest well 

 cleaned of stump sprouts, and have been used for that purpose. Gen- 

 erally, however, the dense canopy prevents the formation of sprouts. 



Because of their rapid growth, both cottonwood and white willow 

 are commercially profitable when planted on bottomland. At an 

 age of 20 years cottonwood averages a height of 72 feet, which means 

 an annual height growth of 3.6 feet. For the same period the white 

 willow has a total height of 50.4 feet, or an average height growth 

 of 2.53 feet a year. 



For this age cottonwood groves average 560 trees to the acre, and 

 yield 3.56 cords of wood a year, while white willow has 1,700 trees 

 to the acre averaging 3.42 cords. From this comparison it will be 

 seen that what cottonwood gains in rate of growth in the individual 

 trees is more than compensated for in white willow by the larger 

 number of individuals to the acre. As a lumber tree the former 

 produces an annual net return per acre of $10.57. As a post tree, 

 the latter produces a net return of $24.01. 



[Cir. 145] 



