March, 1922 



BETTER FRUIT 



Page Nine 



Soil Fertility As Related to Orcharding 



By Clayton L. Long 



Extension Horticulturist, Oregon Agricultural College 



I HE most successful orchardist is the 

 one who recognizes the several 



T 



^ necessary tundanientals ot fruit 

 growing and is capable of classifying them 

 in order of their importance for his own 

 particular orchard. These essentials he 

 groups as follows: 



1. Soil management, including the main- 

 tenance of a proper soil moisture, an abun- 

 dant supply of organic matter incorporated 

 in the soil and a sufficient and properly 

 balanced soil fertility. 



2. Pruning, for the purpose of maintain- 



Two groups 

 of food 



I 



Necessary 

 Elements 



Air 



Food 

 Soil 



Food 



Carbon 

 Oxygen 

 Hydrogen 



Nitrogen 



Phosphorous 



Pot.issium 



Calcium 



Magnesium 



Sulfur 



Iron 



Sources of 

 Supply 



Amounts needed 



Factors limiting total supply 



Air 



Air or water 



Water 



Organic Mattel^ 

 Mineral Matter 

 of Soil 



Soil 

 Soil 

 Soil 

 Soil 

 Soil 



95 + % of food 

 Requirements 



5 - % of food 

 Requirements 



Amount green color leaf sur- 

 face exposed to good lifht. 



Size of feeding and root area 

 and amount of available soil 

 fertility. 



(Nitrogen carrying organic 

 matter being limiting factor. 



distribution of the fruiting wood and for 

 facilitating pest control. 



3. Pest control, including the preven- 

 tion or cure of economic injury from 

 rodent, insect or disease pests. 



4. Thinning of the fruit for the pur- 

 pose of producing a more marketable 

 at a greater profit to himself. 



ing a more equal distribution of light to orchard. No one of them is decided upon phosphorous and potassium— are used lor 

 the entire leaf surface; a common sense or adopted before he determines the effect growth and production m larger quantities 



and may, m the future, become limiting 

 factors in fruit growing, but to date have 

 been supplied in amounts great enough to 

 meet all needs for growth and production. 



it will have upon the system as a whole or 

 upon any one of the others. 



Each step in his system of orchard man- 

 agement either tends to bring this year's 

 crop of fruit to maturity in the most profit- 

 able condition or to maintain the vigor of 

 the tree against its own natural tendency 

 to become old or devitalized. He carries 



These four fundamentals of his business on his orchard practices for the continuation 



THE remaining element, nitrogen, large- 

 ly supplied by the organic matter of 

 the soil, is the one to first disappear from 

 cultivated soils. The organic matter, being 



considers individually, but of a fairly vigorous wood growth as well as the most unstable part of the soil, rapidly 



he not only 



collectively, together making up the one 



most profitable method of handling his 



Compare this apple yield, grown with alfalfa as 

 cover crop, with that in opposite photo. These 

 demonstration tracts arc at Freewater, Oregon. 



to bring about an annual crop of large, 

 perfect, well colored fruit. 



Soil management, the first of these four 

 essentials, and by far the most fundamental, 

 is the subject here treated. The manage- 

 ment of anything, to be a real success, 

 should be based upon a thorough knowledge 

 of the subject to be managed. An orchard 

 soil is no exception. While it is impossible 

 here to make a thorough study of any part- 

 icular orchard soil, it is possible to study 

 a general one. Such a soil is a porous mass 

 of rock and organic p.irticles, moistened 

 with that water retained after thorough 

 under-drainage, ventilated by a slow circu- 

 lation of air and alive with minute organ- 

 isms. 



There are ten elements of materials 

 necessary for tree growth or fruit produc- 

 tion. These are carbon, hydrogen, oxygen, 

 nitrogen, phosphorous, patassium, calcium, 

 magnesium, sulfur, and iron. No fruit 

 tree can live or produce without all of 

 these. 



The first three elements, carbon, hy- 

 drogen and oxygen, usually available in 

 unlimited quantities from air and water, 

 make up approximately ninety-five percent 

 of a fruit tree and its crop. The other 

 seven, nitrogen, phosphorous, potassium, 

 calcium, magnesium, sulfur, and iron com- 

 bined supply the other five percent or 

 thereabout. The last four, calcium, mag- 

 nesium, sulfur, and iron are used by fruit 

 trees in very limited amounts and are suf- 

 ficiently supplied in common orchard soils. 

 Where alfalfa is used as a permanent cover- 

 crop in the orchard, sulfur may be used to 

 advantage. 



Two of the remaining three elements — 



decays and disappears under the usual 

 {Continued on page 26) 



Here is typical apple tree, fruiting on a tract 

 having grass cover crop. It is the same age as 

 the tree shown in opposite column on this page. 



