i()i6 



BETTER FRUIT 



Paffc 7 



Maintaining Soil Fertility Largely A Local Problem 



A. G. Craig, Before the Washington State Horticultural Association, Wenatchee, Washington, December 9, 1914 



THE experiment stations of tlie states 

 of the I'nited States and of Europe 

 have devoted more attention to tlie 

 subject of fertilizers and soil fertility 

 than any other subject in the annals of 

 agriculture. Farmers and fruit growers 

 have also expended vast sums of money 

 experimenting with commercial ferti- 

 lizers. The results of the experiments 

 have been somewhat contradictory and 

 the literature on the subject is more or 

 less confusing. This is proof that the 

 subject of maintaining soil fertility is 

 more or less of a local problem. 



We often hear it said that Washing- 

 ton soils are well-nigh inexhaustible, 

 and indeed it is true that they are rich 

 in many of the elements of fertility. 

 But we now know from experience that 

 the continuous cropping of wheat in 

 the Willamette N'alley in Oregon has re- 

 duced the >ield of wheat from sixty 

 bushels per acre to as low as ten 

 bushels per acre. This is true to a 

 smaller deg}'ee in our own fertile wheat 

 belt. The following is copied from 

 Bulletin No. 121, Pennsylvania Stale 

 College Agricultural Experiment Sta- 

 tion: 



"There is an important need for fer- 

 tility in any orchard that is actively 

 producing and gi-owing. The actual 

 extent of this need can be approximated 

 chemically by determining the average 

 composition of apple wood, leaves and 

 fruit, and by applxing these figures to 

 wdiat may be considered good annual 

 amounts of these products. This we 

 have done both for apples and for a 

 25-bu.shel crop of wheat, with lesults 

 shown in Table I. The annual weights 

 for apples are based on a yearly ]jro- 

 duction of 1(1(1 pounds each of wood and 

 leaves, ami of fourteen bushels of ajj- 

 ples per mature tree. All these amounts 

 are distinctly less than those actually 

 observed and reported, but inasnuich as 

 they give an annual yield of 490 bushels 

 per acre of thirty-five trees they are 

 considered sullicient for the jnesent 

 purpose. 



"In the first place it will be noted that 

 in total food draft the apples exceed the 

 25-bushel wheat crop in every constit- 

 uent except phosi)horic acid, and in that 

 they fall behind bs only half a pound. 

 Notwithstanding this fact, the trees are 

 usually able to maintain themselves 

 much better and longer than wheat. 

 This is probably largely because of 

 their much longer season of root activ- 

 ity, their more natural demands, the 

 annual return of most of the ]dant food 

 in their leaves, and their ability to cur- 

 tail production for one or more seasons 

 when conditions become unfavorable. 

 Without going into details, however, it 

 is quite evident that very important 

 amounts of plant food are annually re- 

 moved by an apple orchard. Scarcely 

 any soil can furnish all these materials 

 indefinitely in the amounts and at the 

 times re(iuired, and unless proper assis- 

 tance is rendered tliere nuist come a 

 time when iiroduclion is mateiially re- 

 duced and off seasons occur. 



"Returning to the table, it is of inter- 

 est to note the relatively large amounts 

 of nitrogen, potash and lime, and the 

 comparatively small amount of iron an- 

 nually taken up by the apples. Nearly 

 all the lime lemains in the wood and 

 leaves, while a large proportion of the 

 potash finds its way to the fruit. 



"This large amount of lime seems to 

 have some significance, so far as the 

 wood is concerned, because, as shown 

 later in several of our experiments, its 

 application has resulted in c(jnsiderable 

 improvement in growth. In the fruit, 

 howevei', very little lime is required, 

 and hence its application should not be 

 expected to afVect the yields materially, 

 and this corresponds with our tield re- 

 sults. Moreover, the total efTect of add- 

 ing lime alone is surprisingly small, in 

 comparison with the large amounts that 

 are taken up. Either these amounts are 

 merely drawn in and deposited mechan- 

 ically by the transpiration stream, and 

 hence are largely without physiological 

 significance, or else the average soil is 

 still able to su])pb' the needed lime. 



"In view of the large amount of 

 potash carried by the fruit, one might 

 suppose that its addition to the soil 

 would be very important in improving 

 \ields, and this idea has been widely 

 proclaimed, especially by those consid- 

 ering only the chemical conii)osition of 

 the fruit. As indicated later, however, 

 it seems tliat most orchard soils are 

 already sufficiently supplied with potash 

 in available forms and that the chief 

 shortages occur in the nitiogen and 

 jihosphates. This is the case notwith- 

 standing the fact that the latter mate- 



rials are actually retiuired 

 able smaller amounts. 



"From these facts it is 

 there is comparatively I 

 between response 

 ments in the case 



in consider- 



evident that 



little relation 



and total require- 



of plant food and 



that something more than a knowledge 

 of the cbenncal composition of the fruit 

 and wood is needed before one can 

 properly fertilize an orchard. Even 

 with the additional knowledge of the 

 composition of the soil, the problem is 

 not nuich simplified, because it is im- 

 possible as yet to duplicate sufficiently 

 the conditions existing in any soil. 

 A chemist may detcrnnne the total 

 amounts of plant food present, but he 

 cannot yet determine their actual avail- 

 ability to the tiees with sufficient accu- 

 racy to be of much value. 



"The ])ractical and proper fertiliza- 

 tion of an orchard, therefore, becomes 

 an experimental problem, and its solu- 

 tion is dependent primarily upon the 

 pomologist or horticulturist, supple- 

 mented by local tests. In other words, 

 the question is not so nuich what 

 amounts of plant food are annually 

 taken up, noi' what amounts are pres- 

 ent, but rather it is what responses are 

 made when certain kinds and (|uantities 

 of plant food are actually added to an 

 orchard soil." 



Results From the Johnson Orchard 

 Experiment. 



"In this ex])eriment fertilizers were 

 applied per acre as follows: Actual 

 nitrogen, .")0 ]5ounds; actual phosphoric 



TABLE I.— THE RELATIVE PLANT-FOOD DRAFT OF WHEAT AND APPLES. 

 (In pounds per acre annually, based on American and Cierman .iverages.) 



Wheal 

 Grain 

 Lbs. 

 Annual weights 1,,'jOO 



Nitrogen (N) 



Phosphoric acid (P0O5) . 



Potash (KoO) " 



Lime (CaO) 



Magnesia (MgO) 

 Ire " ~ 



(FeO) 

 TARLE II.- 



.■iO.O 



in.o 



i).8 

 (I. .SI 



.■i.n 



A pple 

 11'oorf 

 Lbs. 

 3,500 



ll..-! 

 .'i.li 

 (i.fi 



29.1 

 ■1.1 

 0.,5 



Apple 



Leaves 



Lbs. 



3,500 



2.5.6 



5.3 



15.9 



29.5 



8.9 



1.5 



Apple 



Fniil 



Lbs. 



24,500 



16.2 

 6.4 



41.5 

 3.0 

 3.4 

 0.8 



.\pple 



Total 



Lbs. 



31,500 



53.1 

 15.3 

 64.0 

 61.6 

 16.7 

 2.8 



-INFLUENCE OF FERTILIZATION ON YIELDS (JOHNSON ORCHARD). 



1<)08 



1909 

 1910 

 1911 



(Yields in pounds per plat and luishels per acre annually 



I'lul: 1 2 .7 /» ."5 6 7 



Nitrogen Xitrofp'n Phos. Camp. 



Cheel: and anil Cheek and Ferli- Cheek 



Plios. Patash Potash lizer 

 Lbs. Lbs. Lhs. Lbs. Lbs. Lbs. Lbs. 

 90 52S 237 446 57 '/j 759 211 



1908-1912. 

 ,V 



.1/(1- 



niire 



Lbs. 



278 



.1 

 Lime 

 Lbs. 



10 

 Cheek 



Lbs. 

 106 



675 



2,575 



283 



1912 1,024 



Totals 4 years 



0,018 

 3,265 

 7,563 

 1,225 



5,257 



) ,822 



7.816 



696 



1,932 



3.168 



617 



1,382 



3,089 

 3,552 

 1.227 

 1,;t85 



6,621 



2,108 



8,2119 



ISO 



2,008 

 1 .629 

 1,362 

 1,226 



3,5.31 

 6.119 

 4.S71 

 6,698 



1,216 



3.185 



388 



741 



1 ,266 



3,505 



100 



474 



4,557 18,071 15,591 7,099 9,253 17,127 6,225 21,252 5,.530 5,351 



Average yield per 

 acre I bushels) . . . . 



Caiu over av. cheek 



542.1 



377.9 



213.0 



293.5 



277.6 

 103.4 



513.8 180.7 



637 



105.9 160.; 



463.3 —8.3 



Produce 



Wheal, 25 bushels 



yVheat straw. 1 Ion 



Vetch hay. 3 tons 



Alfalfa hay, 6 tons 



Timothy, 2 tons 



Potatoes, 201) bushels . . . 

 Apples, 300 bushels . . . . 

 Fal cattle. 1. 11(10 pounds. 



Milk, 10,000 poinids 



Rutter, 500 pnuiuls 



36 



10 



1211 



:iOO 



48 



40 



90 



25 



57 



1 



Fresh kale, 30 tons 240 



TABLE in. 



Pounds 



Nitrogen Polash Phos. 



14 

 125 



150 



48 



60 



82 



1 



12 



0. 



190 



6 



2 



ll 



25 

 "6 



11 



Nitrogen 



$ 7.20 



2.00 



21.011 



60.00 



9.60 



8.00 



18.00 



5.00 



11.40 



.20 



18.00 



-.Market Value- 



Potash 



•J0.35 



.85 



6.25 



9.00 



2.75 



4.90 

 .05 

 .75 

 .01 



9.50 



Phos. 



•?0.75 



.25 



1 .68 



:j.oo 



.75 

 .85 



1.35 

 .85 

 .85 

 .02 



6.00 



Total 



$ 8.30 



3.10 



31.93 



72.00 



13.10 



12.45 



24.25 



5.90 



13.00 



.23 



63.50 



