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boles formed than those growing in the fields where more complete culti- 
vation was performed. Those growing in the more open fields and where 
the most complete cultivation as to keeping the soil cleaned of all forms 
of outside growth seemed to grow more bushy and to cease growing earlier 
in the summer than the others. The only reasonable opinion to be given 
for this fact is that they were more exposed to the heat of the sun, nothing 
formed a covering to the soil to prevent evaporation and the trees were 
deprived of any sort of shade protection. No forest influence was thrown 
around them. 
It must not be inferred from the discussion of the cultivation here 
given that no cultivation is needed. The young trees must be given culti- 
vation necessary to protect them from weeds and other wild forms of 
growth immediately around them. . . . . The trees at the reservation 
are given the cultivation that can be performed with the means supplied, 
and no more. If more means were provided they would be cultivated 
more and better results might accrue.” 
It can be seen that the Board of Forestry recognizes the fact that 
they are not caring for the young trees in the best possible manner. A 
crop of weeds is not the best way to prevent evaporation from the soil. 
The maintenance of a dust mulch by cultivation will do this and will not 
use food material stored in the soil. A dise harrow or a five-toothed cul- 
tivator run through between the rows after each rain during the summer 
will keep up the dust mulch and keep down the weeds. In other words, 
a forest crop should be cared for just as a corn crop, except that the 
period of cultivation is longer, sometimes three or four years. 
Thinning.—The maximum number of trees per acre at maturity is 
about two hundred. It has already been shown why thinning is bene- 
ficial, so only this remains to be said: a few years after the plantation 
has become well established the process of thinning should begin. The 
weakest and poorest trees and those crowding better ones should be re- 
moved here and there to make room for their more vigorous neighbors. 
Gradually this process should continue, the material being utilized, until 
at maturity the woodlot has the requisite number of good trees and also 
has provided for a permanent supply. 
[28 —23003 ] 
