426 EXPERIMENT STATION RECORD. [Vol.35 



Spring manuring of potatoes liad a somewhat better after-effect on peas than 

 fall manuring. Deep plowing in of both manures for potatoes had a better 

 effect in spring and a poorer effect in fall on the following pea crop than 

 shallow plov/ing. The after-effect of stable manure was greater for peas than 

 that of green manure. Spring manuring of beets had a better effect on the 

 following bean crop than fall manuring, and deep plowing was better than 

 shallow plowing. Stable manure had a better after-effect on beans than green 

 manure. 



Spring manuring of potatoes had a better effect on the rye crop following 

 peas than did fall manuring. Stable manure in this case had a better after- 

 effect than green manure for rye as did also the deep plowing as compared to 

 shallow plowing. 



With rye following beans no difference was observed between fall and spring 

 manuring with green manure, but with stable manure the spring manuring had 

 the greater effect. The after-effect of stable manure on rye following beans 

 was better than the after-effect of green manure. Deep plowing in the fall 

 was better in this case also than shallow plowing, while by spring manuring 

 with green manure the reverse was true. With stable manure depth of plow- 

 ing had no effect. 



The role of nitrifying bacteria in the decomposition of manure, V. G. 

 Smibnov (Zhur. Opytn. Agron., 16 (1915), No. 5, pp. 329-374). — Experiments 

 with artificial manure prepared from horse and cow excrement, sterilized and 

 inoculated with soil nitrifying bacteria under aerobic and anaerobic conditions, 

 are reported. 



Under anaerobic conditions nitrogen losses in the form of free nitrogen were 

 considerable from manure inoculated with nitrifying bacteria. Under aerobic 

 conditions the nitrogen losses were small. 



It is concluded that the participation of nitrifying bacteria in the decom- 

 position of manure served to reduce the quantity of ammonia nitrogen present. 

 Under anaerobic conditions the losses of ammonia nitrogen increased steadily. 

 This is taken to indicate an increase of combined ammonia and a decrease of 

 free ammonia. As the results did not agree no general conclusions were drawn 

 regarding the transformation of albuminous nitrogen. It was further found 

 that the phosphoric acid content of the manure remained unchanged under 

 both aerobic and anaerobic conditions. 



With reference to the conservation of manure and the prevention of nitro- 

 gen losses, it is concluded that conditions should be such as to retard the de- 

 velopment of nitrifying bacteria and to favor the formation of organic acids 

 which will combine with ammonia. 



Green manuring experiments, J. A. Voelckeb (Jour. Roy. Agr. Soc. England, 

 75 (1914), pp. 295. 296; Woburn Expt. Sta. Rpt. 1914, pp. 12, IS; abs. in Jour. 

 Bd. Agr. [London], 22 (1915), No. 4, p. 353). — It was found in these experi- 

 ments that rape was the best green manure for wheat, with mustard second, 

 while the crop after tares was the smallest of the three. 



The activity and availability of insoluble nitrogen in fertilizers as shown 

 by chemical and vegetation tests, F. R. Pember and B. L. Haetwell (Jour. 

 Indus, and Engin. Chem., 8 (1916), No. 3, pp. 246-251, figs. 2). — Pot culture 

 experiments conducted at the Rhode Island Experiment Station with oats, rye, 

 and millet to determine the availability of the nitrogen of dried blood, tankage, 

 castor pomace, rape meal, sodium nitrate, calcium nitrate, cyanamid, and a 

 number of other nitrogenous fertilizers are reported, together with laboratory 

 tests of the activity of the water-insoluble nitrogen in these fertilizers by the 

 alkaline and neutral permanganate methods. 



