434 CALIFORNIA FRUITS: HOW TO GROW THEM 



conducted by Mr. .G. Harold Powell of the United States Depart- 

 ment of Agriculture and his associates. Every grower of oranges 

 should familiarize himself with this work.* 



SOILS AND SITUATIONS FOR THE ORANGE 



While citrus conditions do exist through large areas of Cali- 

 fornia, there is still danger of loss and disappointment through 

 unwary individual investments and unwise locations of citrus 

 colony enterprises. The tracts of land for orange planting even in 

 a favorable citrus climate are limited in area and every citrus 

 climate has numerous places where local meteorological conditions 

 will prove destructive to the profit of the enterprise, if not to the 

 life of the trees. The orange is a hardy tree, judged within its 

 temperature limits, but there is no money in a tree which is sub- 

 jected to any kind of hardship. For this reason the selection of 

 a good depth of strong, free loam should be made, for such is 

 essential not only to good growth of the young tree, but to its 

 support through the long productive life which the orange enjoys. 

 Depth of good soil is not only a storehouse of plant food, which 

 will postpone the use of purchased fertilizers, but it is a reservoir 

 of water so that irrigation can be applied in larger amounts at 

 longer intervals. While it is quite possible to grow an orange 

 tree and to secure good fruit on shallower soils, if conditions are 

 kept just right by frequent use of water and fertilizers in just the 

 right amounts, such conditions impose heavy burdens in their 

 constant requirements of extra care and expenditure, and these 

 are handicaps of no small economic importance. The tree can not 

 live upon climate as a man may, because a tree can not speculate ; 

 it must have a good foundation in the earth as well as a good 

 outlook in the sky. 



Growing orange trees on defective soils has brought disap- 

 pointment and loss in all parts of California. Ample supplies of 

 irrigation water available have encouraged over-irrigation where 

 trees have been planted above hardpan, and drainage is absent. 

 Dying-back and yellow leaf have appeared in some groves and 

 have been accounted for by digging to find the roots bedded ii 

 mud and slush. All plantings over clay sub-soils should be guarded 

 against this danger. Digging deep holes and filling them with good 

 soil is setting a trap for the future failure of the tree unless the 

 deep hole is properly drained by the nature of the sub -soil or by 

 artificial provision. On the other hand, planting over a gravelly 

 sub-soil is often disappointing, because the water passes through 

 the sub-soil as through a sieve and the tree shows distress although 



* "The Decay of Oranges While in Transit from California," by G. Harold 

 Powell, Pomologist in charge of Fruit Transportation and Storage. Bulletin 123, 

 Bureau of Plant Industry, U. S. Dept. of Agr., Washington, D. C., 1908. 



