FORESTRY AND CONSERVATION 387 



for this pest, for when once established among trees it is almost im- 

 possible to eradicate it. 



Cultivation should cease at midsummer, in order not to encour- 

 age too late growth and consequent danger of winterkilling. There- 

 after large weeds can be cut out with a hoe, or a thin crop of oats 

 or buckwheat can be sown among the trees to hold the soil during 

 the drying winds of late summer and early autumn. After the 

 leaves fall, a shallow furrow turned against the trees will prevent 

 exposure of the roots by the late fall and early spring winds. 



The best implement for cultivating young trees is a harrow- 

 tooth cultivator. The horse hoe, with its varied attachments, is 

 useful in the tree plantation, as well as in the fruit and vegetable 



garden. During the first year a two-horse cultivator can be used, 

 ut it should always work shallow; the result, however, is not so 

 satisfactory as with the finer-toothed machine. 



Two or three years, depending on distance and upon the season, 

 should be sufficient for the cultivation of any carefully designed 

 mixture of forest trees. At the beginning of the second season all 

 blanks should be reset, and again the third spring. This should 

 insure a full stand of trees. Thereafter the knife and pruning 

 shears must take the place of the cultivator. 



In river and creek valleys, where water is found at from 5 

 to 20 feet below the surface, cultivation is not ordinarily necessary 

 after the trees are thoroughly established. The same is true in many 

 places on the upland, where shallow depressions catch the run-off 

 from considerable adjoining areas. In such situations the supply 

 of water may be concentrated on any desired part of the depression 

 by running furrows to it from the surrounding slopes. This method 

 has been successfully used by some of the most progressive western 

 farmers. 



Pruning a Young Plantation. In a properly designed planta- 

 tion of forest trees very little pruning is necessary, though the 

 temptation to use the knife is often great. If in passing through 

 the plat a tree of upright habit is found to be forked near the ground, 

 or to be forming two leaders, one of the branches should be cut away. 

 If the shade-enduring trees are found to be overtopping the light- 

 demanding kinds, the former must be headed in. This rule, however, 

 must be used with judgment. It will often happen, as with the oaks, 

 that the more valuable species is seemingly harmed by its neighbors, 

 when in reality it is making strong root growth, and is none the 

 worse for the temporary overtopping. 



Many trees, like the black wild cherry, form a mass of fine 

 branches while young and look as though they would never make a 

 leader and grow to a single trunk. These snould be permitted to 

 grow without pruning in thick-set plantations. As soon as their 

 neighbors begin to crowd them one of the many branches will take 

 the lead, and the plant will assume tree form, the many lateral 

 branches dying off as the stem grows upward. 



It is no advantage to "trim up" young trees by the removal of 

 their lower branches when they reach a height of from 12 to 20 



