WORK OF THE UNITED STATES FOREST SERVICE 



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Figure 17. — Cottonwood planting crew in action in South Dakota ; 1-year seedling 

 being planted 4 feet apart in rows 8 feet apart. 



Figure 18. — When planted on an Oklahoma farm March 5, 1936, these cottonwoods were 

 1-year seedlings. The photo was taken November 10, 1936. The trees are growing 

 into an effective shelterbelt designed to keep sand from a river bed from being deposited 

 on a valuable field. 



Field windbreaks provide protection from winds in a region where 

 natural means of protection are largely lacking. They serve also as 

 snow traps and furnish shade. The trees help to prevent the quick 

 drying and subsequent "blowing" of soils by checking the velocity 

 of the winds. Similarly they protect growing crops from critical 



