226 EXPEEIMENT STATION BECORD. 



crops, and rape or Canada peas for a single crop. Sorghum showed best for a 

 summer forage, and rye or rye and vetch for a fall crop. Crimson clover was 

 not so satisfactory as vetch. In alfalfa experiments Northern seed is noted as 

 being superior to commercial seed, especially that from subtropical and warm 

 humid climates. 



From results of 25 years of crop rotation experiments, in charge of M. F. 

 Miller and C. A. Le Clair, it is stated that " a rotation alone even including 

 legumes is not sufficient to maintain soil fertility providing all crops are re- 

 moved. Rotation maintains productiveness very much better than continuous 

 cropping of any kind. A rotation of corn, oats, wheat, clover, timothy, manured 

 at the rate of seven tons annually maintains the productiveness of the soil and 

 is also financially profitable. It was found profitable to apply manure to con- 

 tinuously cropped land. Continuous fertilizing with commercial fertilizers on 

 continuous wheat at a rate sufficient to supply plant food for a 40-bu. crop an- 

 nually maintains the productiveness as high as does the seven tons of manure 

 annually. Continuous timothy with manure has been one of the most profitable 

 treatments." 



As results of studying the effect of various crop rotations on the physical 

 character of the soil, by M. F. Miller and C. A. LeClair, it is noted that " the 

 system of cropping does not infiuence the mechanical composition of the upper 

 4 ft. of soil, A system of rotation may infiuence the water retaining power of 

 the surface soil by influencing the amount of organic matter present. The sys- 

 tem of cropping apparently has no appreciable effect on the movements of air 

 or water in the subsoil." 



Experiments in the associated growth of corn and cowpeas have shown that 

 " when cowpeas are grown with corn either between the rows or in the row, 

 the nitrates of the soil are not greatly reduced below the amounts present when 

 corn or cowpeas are grown alone. Cowpeas grown with corn does not seriously 

 exhaust the soil moisture, although more water is used than in the case of corn 

 alone. The average height of the corn plant is shortened about a foot when cow- 

 peas are grown in the corn. The number of leaves on the corn plants grown 

 with cowpeas is greater at the time of harvest than on the plants where com 

 is grown alone, but the yield of corn is slightly decreased when cowpeas are 

 grown with corn." 



It appears from data gathered in a study of the development of the maize 

 plant, by J. C, Hackleman and A. R, Evans, " that the most important period 

 in the growth of the corn plant, from the standpoint of soil moisture, is the 

 period from the time the coi'u is usually ' laid by ' until the ear is practically 

 formed. There is a direct relation between the amount of moisture present in 

 the soil and the amount of growth. Clay loam soil gives a larger root develop- 

 ment than sandy loam. The growth of the vegetative part above the ground 

 is not necessarily in proportion to the root growth." 



" In a system of continuous wheat growing followed by cowpeas the same year 

 [this experiment being conducted by C. A. LeClair], the effect of remov.ing 

 cowpeas from the land results in a gradual decrease in the wheat yield, accord- 

 ing to data collected during a period of twelve years. Better results are secured 

 when the cowpeas are disked in rather than when plowed under." 



Growing field root, vegetable, and flower seeds in Canada, M. O. Malte and 

 W. T. Macoun (Canada Expt. Farms Bui. 22, 2. ser. {1915), pp. i5).— This gives 

 general suggestions as to methods of producing seeds of mangels, sugar beets, 

 turnips, carrots, swede beets, parsnips, cabbage, cauliflower, onions, celery, and 

 flowers. 



Farm crops, C. A. Zavitz {Ontai-io Dept. Agr. Bui. 228 (1915), pp. 80, figs-. 

 17). — This gives the results of tests, chiefly variety tests, of farm crops, includ- 



