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cottonwood groves, are greatly in need of renewal, it is here especially 

 recommended. 



Hardy long-lived species, preferably evergreen, should be planted 

 in regular order among the trees of mature or deteriorating groves. 

 Unless grass and weeds are very rank it will not be necessary to pre- 

 pare the soil before planting nor to cultivate afterwards. When, 

 however, the young trees of the understory expand and require more 

 growing space, the mature trees of the upper story should gradually 

 be removed. 



Approved : 



JAMES WILSON, 



Secretary of Agriculture. 



WASHINGTON, D. C., January 25, 1908. 



[Cir. 145] 



