666 FUNDAMENTALS OF FRUIT PRODUCTION 



Probably the most striking fact brought out in a study of the chemical 

 analyses of fruit soils (Tables 17 to 22) is their extreme variability and 

 their frequent wide divergence from the averages of the soils of either the 

 humid or arid sections. It is impossible to associate certain extreme soil 

 types with special crops. For instance a single fruit crop would hardly 

 be expected to do equally well on soil like that shown in columns A 

 and B of Table 20 and those shown in Table 21. The Oahu soils con- 

 tain seven to 20 times as much phosphorus, 50 to 80 times as much potash 

 and 30 to 40 times as much nitrogen as those of the Florida coast; the 

 difference in some of the other constituents is as great or greater. Yet 

 these soils are almost equally well suited to the pineapple, though their 

 fertilizer requirements are somewhat different. The two Hawaiian soils 

 shown in Table 21 resemble each other closely, much more closely than 

 they resemble the Florida soil, but they show a marked disparity in their 

 suitability for fruit culture and the soil that is the richer in the nutrient 

 elements, nitrogen, potash and phosphoric acid, is the poorer when meas- 

 ured in terms of pineapple production. Though the first three soils from 

 Washington whose analyses are given in Table 18 show marked differ- 

 ences in composition, especially in their phosphorus and nitrogen 

 content, all are noted for their fruit production and proof that even a single 

 fruit, as the apple, reaches a higher stage of perfection in one than in 

 the others is difficult. The soil designated in Table 19 as "White land" 

 does not differ greatly in its analysis from the "Redhill" or the "Shot" 

 land, except that it contains less potash and phosphoric acid. These ele- 

 ments are present, however, in larger amounts than in some of the other 

 fruit soils whose analyses are given. Yet this "White Land" is not 

 suited to fruit production and the "Redhill" land and the "Shot" land 

 are among the best fruit soils of the state. The factor determining the 

 difference betwen them is drainage. The analyses shown in columns D 

 and E of Table 18 are particularly interesting in that both soils are from 

 near by fields on Vashon Island, Washington. The differences in compo- 

 sition as shown by the analyses are comparatively small; both are con- 

 sidered well suited to strawberry culture and the average variety does 

 well upon both soils. Yet the Clark variety is reported as thriving only 

 on the one and as failing to produce satisfactorily on the other.^^ 



Evidently the relation of the chemical composition of the soil to 

 suitability for fruit growing is far from well understood, much less 

 established. Without doubt different fruits and possibly distinct varie- 

 ties of the same fruit require, or at least grow better in, soils of somewhat 

 dissimilar chemical composition. However, since present methods of 

 analysis do not differentiate clearly between those requirements they do 

 not actually measure soil productivity as it is expressed in terms of fruit 

 production and they do not afford a very accurate index to fruit crop 

 adaptation. 



