2 . 



liable to be damaged by the exposure. The mulch has another disad- 

 vantage in that it furnishes a congenial harbor for mice and all kinds 

 of insects. A mulch of hay or straw is less objectionable around 

 trees set in the sod, where it is inconvenient or undesirable to culti- 

 vate. Along a hedgerow, for instance, a mulch may be of great 

 benefit. 



SPACING THE TREES. 



The advantage to be gained by continued cultivation of a forest 

 plantation makes rather wide spacing advisable, even though certain 

 species which have a spreading habit may require pruning so that the 

 trunks may grow clear and the cultivation not be impeded. Compen- 

 sation for the wide spaces between the rows can be secured in large 

 measure by setting the trees closer in the rows. The spacing of many 

 plantations is 4 feet by 4 feet, but trees set in that way can be culti- 

 vated only two or three years. Spacing 2 feet by 8 feet gives the 

 same number of trees to the acre, and makes it possible to continue 

 the cultivation much longer. Species which need more room can be 

 set 3 feet by 8 feet or 4 feet by 8 feet, and, as they grow, the space 

 required can be obtained by removing the less promising individuals. 

 The less cultivation that is to be given a plantation the closer the trees 

 should be set; for, in the absence of artificial methods of conserving 

 the soil moisture, the stand itself must be dense enough to shade the 

 ground and furnish a litter which will maintain the proper moisture 

 conditions. Without this the threes will neither grow rapidly nor 

 preserve their vigor. On the semiarid plains, however, wide spacing 

 and frequent cultivation will produce better trees than close spacing 

 and little cultivation. 



SITUATIONS WHERE CULTIVATION IS UNNECESSARY. 



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 con- 

 siderable adjoining areas. In such situations the supply of water 

 may be concentrated on any desired part of the depression by run- 

 ning furrows to it from the surrounding slopes. This method has 

 been successfully used by some of the most progressive western 

 farmers. 



FALL CULTIVATION HARMFUL. 



Cultivation should not be continued too late in the fall, for it tends 

 to produce tender young shoots after the normal growth has ceased, 

 which may not be able to withstand the winter. The wood should 

 have time to harden before cold weather sets in. If the ground has 

 been kept clean, weeds will give little trouble after the middle of 

 August. 



[Cir. 54] 



