23 



Table 16*^ Doptli of humus layer of surface soil and 1923 gr^pe 



yields, Barrett vineyard, LaTvton, Michigan 1/ 



I " ■iiinii m iiiw» m ii.iiiil 11 I II I ■ H W>l ■ ■iiii u I n il ■! i n r iil ■ B m ilw «n lliii « !< ■ i ii m ^MX»i— — M— ■— 



Dopth of 

 humus layer 

 (inches) 



Average yield 

 per acre 



Under 3 

 3 to 5 

 6 to 9 

 ^ver 9 



Total or average 



Tons 



1/ Pvortridge, N. L* and Yoatch, J. 0. Fertilizers and Soils in Relation 

 to Concord Grapes in rSouthv/os tern Michigan. Michigan Agricultural Experi- 

 ment Station Toch* Bull. No. 114* 1931. p. 33, table 6* 



Tahlo 17 ♦ - Results from fertilizer applied to v;oak and vigorous 



grovTing vinos, Barrett vineyard, Lar/ton, Michigan, 1924-1929 1/ 



Weight of 

 prunings, 1923 

 (pounds per vine) 



0.1 to 0.5 

 0.6 to \..% 

 1#1 tn> 1,5 

 1»S and over 



Average 



—— — — I II I wtmmmtmmm i * | 1 * i 



Grape 

 yields 

 per acre 

 (check 



plats) 



» .i*u.iii " LI I II ; 



Tons 

 1.22 



s»ie 



2»71 



3*46 



Increase in yield over check plats for plats 

 fertilized as indicated 2/ 



■ I " ■! ' ■< ■I -■ H « '. ll»illli« ■ II ■ <l A \ 



Aimri0- : Ni- 

 niiira : trate 



2^37 



Tons 



0^89 

 .55 

 #43 



• 55 



Nitrate 

 phos-- 



\ phate 



Tons 



1.02 



• 79 

 41 



• 



«:, 6® 



.^0 



Tohs 

 1.65 

 1.21 

 1.17 



■» « 



1 ''■' 



« CuX, 



Ni- 

 trate 

 potash 



Tons 

 1.53 

 1.21 

 1.28 

 .64 



1»16 



Nitrate 



phosphate 



potash 



Tons 

 1.49 

 1.41 



.73 



1,24 



Average 



all 



plats 



Tom 



1.3£ 



1.03 



1.04 



.63 



1,00 



immmmmmmtmmmim 



>«PI>M*—|III » «'H »! > M »H«.»4W | < » 



Value per acre of increased yield over cost of 

 fertiliser* 2/ at 19E8 pricea 3/ 



©.6 



J 

 % 



to -t^S 1 



X 



to lr5 : 



la 



to 1.5 ; 



1.6 



and over • • 



Average : 





Dollars :I>ollai*^p 



rt 



4 



6 : 



10 



1© 



14 



2 



R : 10 



Dollora :Do liars ;Doilar3 



15 



14 

 6 



15 



14 



16 



2 



14 

 12 

 -1 



13 



10 



Dollars 



13 

 8 

 3 



10 



1/ Adf;pted from table 10, page 37, Michig?3,n Agricultural Eitperiment Station i 



Tech. Eiai, No. 114. 



2/ See footnoto 4, table 15, for rates of applying fertilizer. 



3/ See footnote 1, table 15, for prices of fertilizer ajid grapes. 



