TREES AND SHRUBS 317 



fashion. This is a very common orchard practice in notable 

 orchard districts, as for instance, the Hood River Valley 

 of Oregon. 



Under good systems of orcharding, almonds, pears, 

 peaches, cherries, apricots and oranges are spaced about 

 24 feet apart; apples about 30 feet; walnuts about 38 

 feet; and other trees in like proportion. This wide spac- 

 ing makes necessary several furrows for irrigation between 

 the rows of trees, if the soil is to be saturated thoroughly. 

 Young trees have light water requirements, and one fur- 

 row, not too far from the row of trees is then usually 

 sufficient. Older trees with wide-spreading roots make it 

 necessary to move the furrows farther away. As time goes 

 on, several furrows are made between the rows of trees, 

 so that the farmer is certain that the roots, wherever 

 they may be, are given an ample supply of water. How- 

 ever, if the furrows are carried too near the trees at the 

 beginning of growth, the roots may strike upward and 

 remain near the surface. For that reason, the furrow is 

 placed at some distance even from the young tree, so 

 that the roots will be made to grow downward in search 

 of the moisture soaking down from the furrow. By this 

 method it is possible to establish deep root-systems, which 

 are of first importance in producing trees that may endure 

 ooccasional droughts and always make the best use of 

 the water stored in the soil by rains or irrigation. 



Small furrows, carrying little water, are usually placed 

 about 2^2 feet apart. Deeper ones carrying more water 

 are placed 3 to 4 feet apart. Some orchardists place the 

 furrows 7 or 8 feet apart but make them very deep, and 

 depend on lateral seepage to. moisten all the soil. On 

 average arid soils it is possible that a distance of 7 or 

 8 feet apart for deep furrows is really better than the 



