FIELD CROPS. 143 



than November. Autumn and early winter applications seem to give the best 

 results, as a large quantity of mold can then be worked up with the harrows 

 the next spring. 



" In places where gas lime can not be obtained, and where the tor grass exists 

 as small, isolated patches, the best method of eradication would be to dig it 

 out with a suitable spade to a depth of 3 in. Where large patches occur on 

 land which is not on too steep a slope, the tor might be plowed out. The turf 

 would require to be knocked about with chain or grass harrows until dry. 

 It should then be burnt or left until killed by the weather. . . . Flowering 

 should be prevented by mowing, grazing with sheep, or burning, and young 

 tufts should be grubbed out and burnt when first seen." 



Breeding experiments with winter wheat at Svalof, 1910-1912, H. Nils- 

 son-Ehle (Sveriges Utsadesfor, Tidskr., 22 (W12), No. 6, pp. 307-33J,, pis. 3).— 

 New varieties of winter wheat bred at Svalof and adapted for southern or cen- 

 tral Sweden are described and discussed, and the yields obtained during the 

 3 years are given in detail. 



Some germination experiments, 1910-11, M. Heinrich {Landw. Vers. 

 Stat., 78 {1912), No. 3-Ji, pp. 165-118). — In the case of Anthoxanthum odor- 

 atum, the seeds germinated best in darkness and in a temperature ranging 

 from 5 to 20° C. and changing every 5 days. With Avcna elatior, an increase 

 of 12.7 per cent in the germination was secured when the hulls were removed 

 from the seeds. Poa trivialis, P. pratensis, P. compressa, and P. nemoralis 

 all germinated better in direct sunlight than in diffused light or darkness. 



Contradictory results were obtained with all the tests in regard to germina- 

 tion of seeds placed in cotton, filter paper, sea sand, yellow sand, garden soil, 

 and meadow soil under various degrees of moisture and a uniform periodical 

 change in tlie temperature. 



Seed analyses: Their interpretation and use, S. F. Armstrong (Jour. Bd. 

 Agr. [London], 19 {1913), No. 10, pp. 827-834) .—The author points out the 

 importance of seed analysis, since seeds constitute by far the most variable 

 material the farmer has to purchase; and are at the same time, weight for 

 weight, the most costly. The entire success or failure of a crop (and even of 

 succeeding crops) may also be wholly determined by the kind or condition of 

 the seed sown. Causes of the variation in the purity and germinating capacity, 

 the object of seed analysis, interpretation of results, certificates of purity and 

 germination, and tables showing the 1 per cent by weight grading, are dis- 

 cussed. 



In the author's opinion, to arrive at the cultural value of seeds " it is neces- 

 sary not only to know the percentage of pure seed present, but also the germina- 

 tion capacity of the latter. And here again it is important to urge that it is 

 not merely the proportion of seeds which manage to germinate, but rather the 

 nature or quality of the germination, which is the real measure of the value 

 of the seed. For example, a sample of perennial rye grass which germinates 

 up to 90 per cent in the course of 16 days is not nearly so good as a sample 

 which gives a germination of 90 per cent in 6 days, other things being 

 equal. . . . 



"It is generally agreed that the formula : 



Percentage purity X Percentage germination 

 100 

 gives the real or cultural value of any seed. The main purpose of this article 

 is to show that while this formula is true in theory, yet in practice an addi- 

 tional statement is required indicating the nature of the impurities present 

 and the quality of the germination process. It is on such points as these that 

 seed stations can give reliable information. The numerous seed impurities are 



