DlYISIOy OF CEEMISTRT 105 



SESSIONAL PAPER No. 16 



est and most available forms in wLich to furnish plant food as fertilizers. In order to 

 investigate the relative merits of various forms and applications of fertilizers for the 

 potato crop under the particular conditions of soil, climate, etc., obtaining at Frederic- 

 ton, N.B., and Kentville, N.S., land was set aside, in the spring of 1913, at the Experi- 

 mental Stations at these respective places, and a more or les< comprehensive plan, 

 including the use of the various forms of nitrogen, phosphoric acid and potash com- 

 monly found in fertilizers, inaugurated. The field work has been under the control of 

 Mr. W. W. Plubbard, Superintendent at Fralericton and Mr. W, Saxby Blair, Super- 

 intendent at Kentville, to whom I am indebted for the data and records given in this 

 report. 



Experiments at Frederkton, N.B. 



Fifteen plots of one-tenth acre (A to 0) and three of one-half acre each (P. Q. 

 and R.) were measured off. The series included three check plots, upon which no fer- 

 tilizer was applied. 



The soil was rather light sandy loam, fairly uniform in character' and apparently 

 well drained naturally. For many years it had been in hay and the last previous man- 

 uriiig had been two or three years prior to this experiment. In October, 1912, it had 

 been ploughed and during the first week of May, 1913, it was thoroughly worked with 

 the disc harrow. This was followed by cultivation continued every ten days until the 

 time of planting. Shallow furrows were then opened up 30 inches apart and to a depth 

 of 3^ inches. 



The fertilizer was distributed by hand as evenly as p.>ssiblc along the bottom of 

 the furrows and lightly covered with soil. Commercial New Brunswick White Stock 

 potatoes were used as seed and planting was done on June 19th. 



Throughout the season due attention was given to the pr€p?r cultivation of the 

 crop, which was twice sprayed with Bordeaux mixture and Arsenoid. The vines were 

 killed by frost on September 28th, but digging had to be deferred until October 23rd, 

 owing to continued wet weather, which, however, did not adversely affect the crop. 



In Table I the various fertilizers and the amounts applied per acre are given, 

 together with the total and marketable yields of potatoes obtained. Ne': results after 

 deducting the cost of fertilizer have been calculated, valuing the maiketble tuber at 

 44 cents and the culls at 20 cents, per bushel, thus showing the gains and losses per 

 acre from the use of fertilizers throughout the series. 



Experiments at Kenta'ille, N.S. 



This series comprised twenty-four plots of lio acre each and ii^.cluded four to 

 which no fertilizer was applied, to serve as checks. 



The land had never been cropped and was only clea'red of stumps the previous 

 season, many roots still remaining. The soil was a sandy loam of medium to poor 

 quality?, but fairly level and uniform. 



The fertilizer was broadcasted evenly by hand and harrowed in just before plant- 

 ing. A uniform strain of Green Mouniain potatoes was used for seed. The rows 

 were 33 inches apart. Planting was on June 6. Cultivation was given as necessary 

 and the crop was twice sprayed with Bordeaux mixture and Paris green. At the 

 close of the season the ' stand ' appeared to be exceptionally even. The crop was 

 du^ September 30. The data and calculations therefrom, similar to those given for 

 Fredericton, are presented in Table IL 



