CHAPTER XXXV 

 ORCHARD SOILS 



All field crops are influenced more or less by the kind of soil in which 

 they are grown. The same may be said of all fruit crops. Just as some 

 land is classed as good for general crops so some may be classed as good 

 for orchard fruits and just as some is considered good for wheat but poor 

 for alfalfa, so some may be good for pears but poor for strawberries. In 

 a way the factors that are important in determining the value of a particu- 

 lar soil for field crops are also important in determining its value for fruit 

 production. However, were the judging of soils for general farming 

 purposes and for orcharding to be placed on a score-card basis the cards 

 would differ considerably in a number of respects. 



For field crops, both surface soil and subsoil are important in deter- 

 mining relative value of the land but the surface soil is generally regarded 

 as of far greater importance. For fruit crops in general they are of more 

 nearly equal significance. Indeed there are many conditions presented 

 in which there is little doubt but that the nature of the subsoil is more 

 significant than that of the surface soil. For field crops physical and 

 chemical conditions are generally considered of substantially equal 

 importance in determining productivity and suitability to individual 

 crops. Though chemical composition is likewise important in the produc- 

 tion of trees and other fruit plants, physical condition is a first considera- 

 tion. The fact that certain fruits, such as the apple, are grown with equal 

 success in some of the heavy clay loams of western New York, the light 

 sandy loams of New Jersey, the loess bordering the Missouri River, the 

 adobes of the Rogue River valley, Oregon and the volcanic ash of the 

 Hood River section of Oregon appears to contradict this; nevertheless 

 closer analysis reveals certain common characteristics of their physical 

 condition — a similarity much greater than is shown in a comparison of their 

 chemical composition. 



CONSIDERED FROM THE STANDPOINT OF PHYSICAL CONDITION 



Chief among the physical characteristics desirable in an orchard 

 soil are porosity and thorough aeration, coupled, if possible, with depth. 

 The loess soils of the Mississippi, Missouri, Rhine and Hoang-ho val- 

 leys are among the best in the world for the fruits that will grow in 

 the climates of these respective regions because they are extremely deep, 



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