638 EXPERIMENT STATION EECOED. 



solids ranged from 5.39 per cent in tlie potatoes with low dry matter content 

 to 6.4!) per cent In the potatoes with high dry matter content. The percentage 

 of ash and fiber did not vary much, but the content of other nonuitrogenous 

 snl)stances increased with the dry matter. 



Experiments with barnyard manure and commercial fertilizers for pota- 

 toes, 1904-1907, \V. Christie (Ber. Hedemaikens Amts Forsogsstat. Virhs., 

 3 (1907). pp. 5-51). — The data secured in 28 different series of fertilizer ex- 

 periments with potatoes showed that the best general results were obtained 

 from 200 kg. of 20 per cent superphosphate and 100 kg. of 37 per cent potash 

 salt applied with 70,000 kg. of barnyard manure per hectare. The same 

 application with the potash omitted apparently increased the starch content 

 to some extent. An application of 350 kg. of 20 per cent superphosphate, 200 

 kg. of 37 per cent potash salt, and 160 kg. of sodium nitrate per hectare pro- 

 duced as heavy yields as the use of 70.000 kg. of barnyard manure, but gave a 

 somewhat higher starch content than the use of the manure alone. 



[Trials with sugar beets and potatoes] (Univ. Col. Reading, Agr. Dept. 

 BuL 2, pp. 12). — Cooperative sugar beet experiments were made with the 

 Kleinwanzleben and Improved White varieties. The yield of roots ranged 

 from 12* to 24A tons i»er acre. Improved White being the better yielder. The 

 sugar content of the roots varied from about 16 to IS per cent, Kleinwanzleben 

 being generally the better of the two varieties. 



The varieties of potatoes compared belonged to the Up-to-Date, Maincrop, 

 Imperator, and Abundance groups. In the Up-to-Date group 1 oz. of seed 

 potatoes produced on an average 1 lb. of crop in the tirst year, and 0.77 lb. in 

 the follownng season. The next best yield was obtained in the Imperator 

 group, being 0.S7 lb. per ounce of seed potatoes the first year and 0.51 lb. the 

 second. Results with Irish, Scotch, and English seed 4)otatoes in all trials 

 showed that the best and largest crops were obtained from the Irish and the 

 second best from the Scotch strain. 



Experiments on the defoliation of sugar beets, F. Strohmkr, H. Briem, 

 and O. Fallada (Mitt. Clam. Tech. Vers, titat. Cent. Ver. Riibenz. Indus. 

 Ostcrr.-Ungar., Xo. 198, pp. 1-12). — ^After briefly reviewing the results obtained 

 l)y different investigators along this same line, the authors present and discuss 

 the data secured in their own work. Beets were grown on 5 plats, the seed 

 being planted April 6, and the crop being hoed on April 17, May 6 and 20, and 

 June 6. On the last-mentioned date the beets were thinned and a top-dressing 

 of nitrate of soda was given. 



The comparable i-esults on the different plats were as follows : Plat 1, de- 

 foliated July 12, produced 40.25 kg. of leaves and 110.2 kg. of roots; plat 2, 

 defoliated July 30, 41.50 kg. of leaves and 104.3 kg. of roots ; plat 3, defoliated 

 August 24, 87.50 kg. of leaves and 132.5 kg. of roots; plat 4, only partially 

 defoliated ou August 24, 38 kg. of leaves and 126.5 kg. of roots ; and plat 5, on 

 which the plants were allowed to retain their leaves, 50.60 kg. of leaves and 

 174 kg. of roots. The conclusion is drawn that complete, as well as partial, 

 defoliation of the sugar beet reduces total yield as well as sugar production, 

 and that this reduction is greatest when the leaves are removed immediately 

 preceding that period of growth in which the greatest sugar formation in the 

 leaves takes place, which is about the end of July and the beginning of August. 

 It was further found that early and complete defoliation increased the ash 

 content and the crude fiber of the roots and in general reduced their quality. 

 Defoliated beets showed about the same changes that are shown in beets grown 

 with insufficient light. The data also indicate that the oxalic acid content of 

 the dry matter of the leaves is considerably higher during all phases of the 



