B34 fiXtEBIMENT STATIOK RECORD. 



under test Agnelli headed the list with a yield of 2G.700 lbs. of tubers and 

 4,486 lbs. of starch per acre, the avei*age staix-h content being IG.S per cent. 

 Fiirsst Bismarck, the variety ranking first in starch content with 19.5 per cent, 

 yielded 18,307 lbs. of tubers and 3,5G9 lbs. of starch per acre. 



In fertilizer experiments, in which an application of 223 lbs. of nitrate of 

 soda and ITS lbs. each of 20 per cent superphosphate and 37 per cent potash 

 salt was used, the yield of potatoes was apparently increased from 20,897 

 lbs. — the yield of the unfertilized plats — to 24,950 lbs. per acre. The quantity 

 of starch produced per aci*e on the unfertilized plats was 4,103 lbs. and on the 

 fertilized plats 4,521 lbs. The use of the fertilizer, on the other hand, seemed 

 to have decreased the starch content from 19.7 to 18.2 per cent. 



In another series of experiments with the same varieties of potatoes the 

 effect of the application used in the previously described tests was compared 

 with the I'esults secured from the use of 134 lbs. each of niti'ate of soda, 20 per 

 cent superphosphate, and 37 per cent potash salt, given with 17,800 lbs. of 

 barnyard manure per acre. The check plats yielded 17,827 lbs. of tubers per 

 acre, the plats receiving commercial fertilizers alone 21,529 lbs., and the plats 

 treated with commercial fertilizers and bai'nyard manure 24,048 lbs. The 

 yield of starch for the 3 series of plats was 3,284 lbs., 3,622 lbs., and 4,121 lbs. 

 per acre, and the average starch content 18.3, 16.8, and 17.1 per cent, respec- 

 tively. F. W. WOLL. 



The influence of the vegetative period and of the fertilizer used on the 

 chemical composition of potato tubers, P. Vageler (FiihUiig's Landw. Zty., 

 55 (1906), Xo. 16, pp. 556-563). — It is pointed out from the results of experi- 

 ments that the specific gi-avity and the content of dry matter increase with the 

 length of the vegetative period. Mineral matter and nitrogen were not taken 

 up by the tubers after the end of July. As the vegetative period progressed 

 the quantity of stored starch increased, the increase being greatest in August, 

 but somewhat reduced in September. 



A general application of lime, barnyard- manure, or the two fertilizers given 

 together, increased the water content, ash, chlorin, potash, total nitrogen, 

 nitrogen-free extract, sugar, and dextrin of the tubers. The use of barnyard 

 manure increased the quantity of crude fiber, while liming reduced it. Without 

 a general application the use of potash increased the water, ash, chlorin, potash, 

 and protein content, and in a lesser degree the nitrogen-free extract and sugar 

 content, while phosi)horic acid increased in a lesser degree the moisture and ash 

 content, the quantity of nitrogen compounds, with the exception of the amid 

 and total soluble nitrogen content, and nitrogen-free extract. The nitrogenous 

 fertilizers largely reduced the specific gravity, ash, phosphoric acid, starch, and 

 crude fiber, while the quantity of all other components was increased by this 

 treatment. 



In connection with liming, applications of potash gave an increase in the 

 moisture content, ash, nitrogen-free extract, insoluble albuminoids, and starch. 

 The use of phosphoric acid remained neutral with reference to water, total ash, 

 chlorin, potash, protelds, and sugar, but its use increased the specific gravity 

 and the phosphoric acid, total and insoluble nitrogen, and crude-fiber content, 

 while the quantity of soluble ash, soluble amid, and albuminoid substances and 

 starch were greatly reduced. An application of nitrogen favored an increase 

 in specific gravity, water, phosphoric acid, and all nitrogenous substances with 

 the exception of albuminoids. The quantity of total ash, soluble ash, chlorin, 

 potash, starch, and to a very small degree crude fiber, were reduced through 

 nitrogen fertilization. 



With barnyard manure as a general application potash increased the water 



