1918] FIELD CHOPS. 735 



the results fully discussed. Tabulated data show the total dry weight of the 

 shoots and roots of the crops and weeds, and tiie average dry weights of the 

 shoots of each. In addition to the pot experiments, an attempt was made to 

 throw some light on the question of toxicity by a series of water cultures made 

 in 1915, in which v/heat was grown alone and with S. arvenis and A. agrestis. 



No evidence or indication was forthcoming to show that any toxic action was 

 involved. It was obvious, ho\\ever, that the mere competition of plant with 

 plant, irrespective of species, had much to do with plant development, and that 

 the time and duration of such a competitive check were the chief factors 

 involved. Differences between pots in each set were regarded as accidental 

 and not due to any inherent quality of the soil, as no definite correlation was 

 observed between the 1915 crop from any one pot and the 1916 crop from the 

 same pot. This is deemed to be further evidence of the absence of toxic sub- 

 stances, or at least of any toxin capable of remaining in the soil unchanged 

 from one season to the next. 



Wheat-rye hybrids, E. A. McFadden (Jour. Heredity, 8 {1917), No. 7, pp. 

 S35, SS6, fig. 1). — The author describes a wheat-rye hybrid secured from a 

 cross of Turkey winter wheat with Swedish rye in the summer of 1915. 



The most noteworthy differences between the hybrid and its parents were the 

 number of spikelets on the normal spike and the length of the culms. The 

 hybrid possessed 14 or 16 pairs of spikelets per spike, with culms intermediate 

 in length between the two parents. The plant was thrifty in appearance and 

 produced 25 vigorous culms that developed heads and also several tillers that 

 did not develop fully. The first spikes to appear produced no seed, due to the 

 failure of normal pollen grains to develop. A few of the flowers on later spikes 

 were hand-pollinated with pollen from Kharkov winter wheat, resulting in the 

 production of three seeds, two of which produced vigorous plants in the fall 

 of 1916, although neither survived the winter. 



Assuming that hardiness is a recessive unit character, the author asserts that 

 the hybrids could not be expected to survive a winter when nearly all unpro- 

 tected wheat winterkilled. Working on this hypothesis, hybridization work 

 along the same line was to be continued in tJie summer of 1917 on a larger 

 scale, and the Fi and Fj plants carried through the winter in a greenhouse. 



Winter forage crops, P. B. Kennedy {California Sta. Circ. 189 {1918), pp. 

 11). — Brief notes are presented regarding the production and use of the fol- 

 lowing crops for winter forage in California : Field peas, common and hairy 

 vetch, horse beans, rape, kale, giant marrow cabbbage, white mustard, root 

 crops, bur clover, sweet clover, miscellaneous grasses, rye, and barley. 



Report of the department of agriculture [of New South Wales] for the 

 year ended June 30, 1916, G. Valdee {Rpt. Dept. Agr. N. 8. Wales, 1916, pp. 

 25-29, 36-Jt2, 99-102, 109, 110, US, lU-116, pis. 4).— Field tests at several ex- 

 perimental centers are reported with wheat, corn, oats, potatoes, cotton, rice, 

 and numerous forage crops. 



[Field crops work in Java], C. van Rossem {Dept. Landb., Nijv. en Handel 

 [Dutch East Indies], Meded. Agr. Chem. Lab., No. 15 {1917), pp. 135). — Fer- 

 tilizer and cultural experiments, chiefly with rice, and studies of economic phases 

 of agriculture on the island are reported in detail for the year 1915-16. 



The production of alfalfa seed in southern Idaho, L. C. Aichee {Idaho 

 Sta. Bui. 101 {1917), pp. 20, figs. 9). — Approved methods of alfalfa seed pro- 

 duction under irrigation in the Snake River Valley of southern Idaho are 

 described, and production on dry land is briefly outlined. Alfalfa seed is said 

 to be produced in this region at elevations ranging from 2,000 to 5,000 ft., the 

 principal factors involved being climate, moisture, wind, and insects, especially 



