882 



Detailed statements of the yield of large and small potatoes for each 

 plat, the net value of the marketable potatoes, and the net gain or loss 

 are tabulated for each experiment. 



The highest yields from fertilized plats were practically identical [in experiments 

 Nos. 1 and 2] and were secured in both cases from the chemical manures: [in experi- 

 ment No. 3] the barnyard manure gave the highest yield, though this yield was lower 

 by 20 bushels per acre than in the case of the others. In other words, the fertilizers 

 increased tlie yield 1^86 pounds per plat, or 207 jter cent in No. 1, 423 pounds or 236 

 per cent in No. 2, while in No. 3 the increase was but 2.">8 pounds or 100 per cent. 

 This would seem to indicate what is frfcjuently insisted upon, that, other things 

 being equal, fertilizers act more favorably and nniforinly on laiul in which the 

 previous culture and treatment have been good. * * * 



The number of small potatoes was also decidedly reduced by the use (if manures, 

 though it was iuipossildc to draw a strict line between merchantabk- and unmer- 

 chantable tubers. « » » 



In exjterinient No. 1 the yields from the sulphate of potash w«'re 14.8 bushels or 10 

 per cent greater than from the muriate ; in experiment No. 2 the muriate gave 20.5 

 bushels or 13 per cent more than the suliihate; in exjieriment No. 3 the yields from the 

 two were practically identical ; the yield from the use of kainit was in all cases much 

 lower than from the other forms <d' jiotash used. Averaging the three experiments, 

 the yields from the muriate and suljihate were practically identical, while that from 

 kainit was 10 per cent lower than the average of the yields from the muria e and sul- 

 phate. 



These results are in general in accord with those secured in 1800 an<l confirm the 

 statements tluii made, viz, that in the use of muriate or snljihate the main consider- 

 ation is tin- cost, the cheiiper miiriati" being (juite as elfective as the sulphate, and 

 that thi- direct applieation of large quantities of kainit is not advisaJ>le for potatoes, 

 for while the actual jxttash may be quite as etlective in increiujing the yield as in 

 the other forms, it has a ti-ndency to injure the plants and thus prevent a full 

 sl:niil. ' * 



In all the exiieiiinents there was an increase from the use of nitiogen. and in 

 experiments Nos. 2 and 3 it ]iroved necessary in order to secure a prolil. * • * 



In two eases out of three there was a greater gain from the use of dried blood. 

 With the exce]>tion ofexiieriment No. I, where the nitrate seems to have been without 

 appreciable elbet, the increase in yield from the two forms is very uniform. The 

 average yield of all the exjtenments is increased 29.ij per cent by the use of nitrate 

 of soda and 3r>.9 i»er cent by the use of dried blood. The results of these experi- 

 ments therefore sim])ly indicate that where nitrogen is found u.seful, such readily 

 available forms as dried blood may be cjuite as eft'ective as the more soluble nitrate. 



AUowino- 40 cents per bushel for merchantable jiotatoes and .^30 per 

 acre for the cost of growiiii; potatoes, exclusive of numures, "the profits 

 per acre secured from the dinciciit methods of mnntiriiii;- iip]to;ir as fol- 

 lows : " 



K\|)t 1. Kxpl.'J. Kxpt.3. 



Barnyard manure alone $4.02 — 12.40 $li.,'>2 



Barnyard manure and chemical manures 13.01 12.23 0. II 



Chemical manures alone 15.78 10. tVl 7.44 



A ])rotit is secured in all cases except tViun barnyard manure in exj)erinient No. 2. 



The chief conclusions to be drawn from these experiments are that (1) on the 

 whole the use of manures was profitable; (2) the best results were secured from the 

 use of chemical manures; (3) kainit was less etfective than either muriate or sul- 

 phate of potash, ami the sulphate did not produce larger yields than the muriate; 

 (4) nitrogen was a valuable ingredient of potato ujanurcs. 



