130 Kansas Academy of Science. 



western Kansas show differences of from ten to forty percent 

 in favor of the grain sown in furrows. 



YIELD. 



It has also been shown that the yield of grain sown in fur- 

 rows is as high, and sometimes higher, than when sown in the 

 ordinarj^ way, even when no winter injury occurs. 



The substitution of the grain drill for the old methods of 

 seeding broadcast has no doubt reduced the damage from 

 winterkilling very materially, and there is little doubt that the 

 time will come when the drills now in use will give way to 

 other types which make a larger furrow and leave more prom- 

 inent ridges for the protection of the grain. 



KIND OF SOIL AND MOISTURE CONTENT. 



A study of relation of kind of soil and moisture content of 

 the soil to temperature and winterkilling has proved a very 

 complicated and interesting problem. Who can tell, for ex- 

 ample, which is colder during the winter — a dry soil or a wet 

 soil, a clay soil or a sandy soil. If there is a difference, on 

 what does it depend? The question is not only interesting, it 

 is important, since the winter survival and spring condition of 

 important crops like winter wheat, alfalfa, clover, etc., depend 

 on the temperature to which they are subjected. 



The problem has been studied two winters by recording the 

 temperature one, three and six inches deep of three plots of 

 clay, three of silt loam, and two of sand, each containing differ- 

 ent quantities of water. Twenty-four electric thermometers 

 were used to record the temperatures. Winter wheat, winter 

 oats and winter barley were grown on each plot to determine 

 the effect on survival. 



The relation was found to be very complex, the net result 

 depending not only on the single factors studied, but also on 

 the degree and duration of cold weather, whether the soil was 

 frozen, and upon the rate of change of air temperatures. 



To be brief, two seasons' results indicate that a wet clay or 

 loam is warmer than a dry soil of the same kind (i. e., has the 

 highest daily minimum temperatures) as long as the ground 

 is not frozen, due to the specific heat and the latent heat of 

 fusion of the water contained in the soil. When the soil be- 

 came frozen, however, directly opposite results were secured. 

 This reversal was apparently due to the difference in specific 



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