26 BULLETIN 316, TJ. S. DEPARTMENT OP AGRICULTURE. 



with sediment, or cut away by the river, is too valuable agriculturally 

 to be used for forest plantations. This leaves only overflow lands 

 for forest purposes, and the condition of these is so unstable as to 

 make the artificial establishment of plantations too precarious an 

 investment to attract capital. The inferior timber on the ground 

 and the natural reproduction will therefore continue to be utilized 

 instead of better species being planted. Under these conditions the 

 probability of success in forest management is greater with willow 

 than with cottonwood. 



The main problem in the management of bottom lands is how to 

 encourage the best species. In this discussion the lands considered 

 are those lying below the 35-foot stage of the river. Above this 

 mark the willows are usually replaced by better species. The lower 

 areas are covered by a mixture of black willow, cottonwood, and 

 sandbar willow, the last being both the most prolific and the least 

 desirable. In the management of such areas the only way at present 

 of encouraging the best species is to cut intelligently the material 

 used in revetment work. By limiting the cuttings to stands of 

 sandbar willow and leaving the cottonwood and black willow, the 

 prevalence of the sandbar willow can be much reduced. In mixed 

 stands, 7 to 12 years old, where all three species occur, all the cot- 

 tonwood and enough of the black willow to stock the ground com- 

 pletely should be left. If from 200 to 300 trees of cottonwood or 

 black willow be left to the acre, the first crop of willows for revetment 

 will suffer but a slight reduction and the second crop of sprout growth 

 will receive but little shading from the trees left. The third crop of 

 revetment willows will necessarily be smaller, but such a thinning 

 can easily be made profitable; then after the period of these two 

 crops, ranging from 10 to 15 years, the original trees left will soon 

 make a complete canopy. By this method, at practically no ex- 

 pense more than directing the cutting of the brush, a worthless 

 area covered with mixed growth may be converted into timberland 

 of considerable value. In further thinnings the cottonwood, if 

 present, should be favored except on land that is receiving large 

 accretions. On such land the black willow generally survives the 

 cottonwood. 



CHARACTERISTICS OF WILLOW WOOD. 



Willow is characteristically a light wood. It varies considerably 

 in weight in different species and under different growing conditions. 

 The wood of the slow-growing species and shrubby forms is usually 

 heavier than that of the larger and more rapid-growing species. 

 The diamond willow is heavier and harder than the other native 

 willows of economic importance. There is little difference in the 

 weight of the wood of black, white, and crack willows, the specific 

 gravity ranging from 0.4 to 0.45. 



