FIELD CROPS. 227 



always most injurious when made 10 weeks before planting. With au increased 

 yield of dry matter there was usually a decrease in nitrogen yield. 



On clay soils the application of straw did not uniformly decrease the yields. 

 In the presence of alkaline fertilizers and nitrate of soda the straw showed a 

 greater injury to dry matter and nitrogen yields than in the presence of acid 

 fertilizer and nitrate of soda. In the presence of alkaline fertilizers without 

 nitrate of soda the injury was less than with the nitrate, while in the presence 

 of acid fertilizers without nitrate of soda the effect of the straw was similar to 

 that in the presence of alkaline fertilizers with the nitrate. Where there 

 was injury with the deep application of straw it was always greater than 

 with the shallow application. In the presence of nitrate of soda the early 

 (10 weeks) application of straw seemed to produce greater injury to the 

 crops than the late application, while in the absence of nitrate of soda the 

 late application of straw apparently caused the greater injury. With an 

 increase in yield of dry matter, the nitrogen yield decreased. 



The data are given in tabular form. 



On the details of development of cereals, O. Schmidt (Land'W. Jahrh., ^5 

 {1913), No. 2, pp. 261-32Jt, pi. i).— This reports results of experiments to dis- 

 cover characteristics tliat may be used to determine different varieties. 



It is noted that with the exercise of great care varietal differences in the 

 root systems or in the leaf and si)ike arrangements may be detected, especially 

 in the seedling cereal. Great differences were observed in the length of the 

 vegetative period and the lateness or earliness of the shooting of the spike, but 

 these differences could not serve as variety characteristics as they were so 

 much influenced by climate, and in the young plant by size, specific weight of 

 the seed, and morphological characters. From the results of the investigation, 

 therefore, the author concludes that the observed characteristics of any variety 

 iiiay vary. 



The normally formed cereal stalk and its significance, H. Plahn-Appiani 

 (Ztschr. Pflanzenzuclit., 2 {19U), No. 1, pp. 27-^7, figs. ^).— This article dis- 

 cusses the relations of length, thickness, and weight of internodes. 



It is pointed out that these relations are not influenced to any considerable 

 extent by heredity, and should not be considered a factor in selection breed- 

 ing, since they were more influenced by environmental factors such as stand, 

 weather, and mechanical injury, as by insects, animals, or wind. The correla- 

 tions of these structure factors of the internodes seemed to have no bearing 

 on the yield. 



Experiment to determine the influence of age and light on the germination 

 of grass seeds, H. Reiling (Keimversuche mit G-mseni zur Ermittlung des 

 Einflusscs, den Alter und Licht auf den Keimprozess ausiiben. Inaug. Diss., 

 Univ. Jena, 1912, pp. 87). — Experiments are reported with Holcus lanatus, Poa 

 pratensis, Alopecurus pratensis, and Festuca pratensis. 



It is noted that the smaller seeds of these species are not at an optimum con- 

 dition for germination immediately after harvest, but approach that condition 

 in about 6 mouths. Light is a favorable factor to germination, but with in- 

 creased age of the seeds seems to be less important. Good ventilation and dry- 

 ness of the seeds during storage favored the germination process. The data 

 are given in tabular form. 



Some practical hints in breeding grasses, Raum (Ztschr. Pflanzenziicht., 2- 

 {1914), No. 1, pp. 39-50). — This article discusses methods of stock and seed 

 propagation, transplanting seedlings, prevention of cross fertilization, and 

 harvesting the mature plants. 



Alfalfa and sweet clover, G. Roberts, E. J. Kinney, and H. B. Hendrick 

 {Kentucky /Sto. Bui. 178 (1914), pp. 3-34, fiffs. iO).— This bulletin contains in- 



