FIELD CROPS. 881 



Studies as to the competition of cereals indicate that " a larger percentage 

 of plants originating from shrunken seed than plump seed are crowded out." 

 This Indicates the importance of natural selection in maintaining vigor and 

 yield. 



In a test of 16 varieties of corn Hogue Yellow Dent and Leaming produced. 

 8,530 and 7,155 lbs. of dry matter per acre, respectively, these being the highest 

 yields. 



The amounts of organic matter and nitrogen added to the soil by alfalfa and 

 clover roots were determined. In 1 field 2.3 tons per acre of organic matter 

 were added by the first 8 in. of alfalfa roots, and 0.9 ton by the 3 in. stubble. 

 Another field contained 3 tons per acre of organic matter in the first foot of 

 soil, containing 125 lbs. of nitrogen, and another field 1-year old 2 tons of 

 organic matter and 72 lbs. nitrogen. A clover field sown in the spring showed 

 in August 1.25 tons of organic matter in the roots and 44 lbs. of nitrogen, and 

 2.25 tons of organic matter and 137 lbs. of nitrogen in the tops. An old alfalfa 

 field showed 2.55 tons of organic matter and 105 lbs. of nitrogen per acre in 

 the first foot of soil, and 2.05 tons of organic matter and 65 lbs. of nitrogen in 

 the next 10 ft. 



Five crops of winter wheat produced on summer tilled land at the North 

 Platte substation show that "a fair average of wheat planted at the proper 

 time and of the standard variety is 46.7 bu. per acre. This is 6 bu. more than 

 twice the yeld from land, not summer tilled." 



Two common spring wheats have averaged 20.96 bu. per acre or 2 bu. less 

 than the 4 leading durum varieties during the past 4 years. Among oat 

 varieties Kherson held first place without a close rival until 1908 when the 

 Burt oat was introduced. Since that time the yields have been about equal. 

 Common six-rowed barley averaged. 39 bu. per acre on summer tilled land as 

 compared with from 20 to 25 bu. on land continuously cropped. It has proved 

 the best variety for this region. 



On disked corn fields oats yielded 38.6 bu. per acre, barley 35.3, emmer 34.9, 

 durum wheat 23.4 and hull-less barley 18.4 bu. during the past 4 years. As 

 compared with broadcast seeding and harrowing " drilling has increased, the 

 yield of spring wheat 7.4 bu. per acre, of barley 7.7 bu., of oats 10.3 bu. and of 

 emmer 10.8 bu." 



During the past 6 years from 10 to 35 varieties of corn have been tested 

 with an average yield of 25 bu. per acre and a range from almost a failure to 

 52 bu. per acre. Substation Calico, a medium-size corn, may be considered one 

 of the best. 



A brief progress report of rotations and tillage methods indicates that sum- 

 mer tillage has increased the yield of spring grain but not sufficiently to warrant 

 urging its general adoption. It has more than doubled the yield of winter 

 wheat. Corn has usually yielded more heavily with continuous cropping but 

 in 1910 it yielded 2J times as much on summer tilled land as on any of that 

 continuously cropped. 



Soil moisture studies indicate that the moisture content may be increased to 

 an indefinite depth depending on the character of the soil, precipitation, and 

 tillage. Water to the amount of 6 or 8 acre inches may thus be accumulated. 



Alfalfa growing is discussed and directions are given for securing a sorghum 

 crop. 



[Nevada field crops experiments], P, B. Kennedy and G. H. Tbtje {Nevada 

 Sta. Bui. 73i, pp. 19, 20, 29-31, 33-35).— A brief progress report of alfalfa 

 investigations precedes short histories and descriptions of Medicago ruthenica, 

 S. P. I. 24,451 ; M. falcata, S. P. I. 23,625 ; Grimm alfalfa, S. P. I. 25,102 ; Old 



