ANNUAL REPORT, 1945-46 " 9 



arises; for it is in the early stages of growth that magnesium is required and ap- 

 plying salts of magnesium after the symptoms appear is generally much too late. 



Long-Time Fertility Tests. (Karol J. Kucinski, Walter S. Eisenmenger.) 

 Fifty to sixty years ago a series of test plots was established to study the effects 

 on the soil and crops of a long-time fertilizer program. Where the plots were 

 treated singly with either nitrogen, potash or phosphorus, the nitrogen plots 

 showed the greatest response. Yields of hay ranged 2 to 2.5 times as great on 

 plots receiving lime as on those not limed. Rabbits fed grass grown on limed 

 plots made greater growth than rabbits fed grass grown on unlimed plots. Sim- 

 ilar results were obtained where cabbage was used to feed the rabbits. 



Sunflowers and Their Possibilities. (Karol J. Kucinski and Walter S. Eisen- 

 menger.) Although the 1945 growing season was generally unfavorable for most 

 farm crops because of abnormal rainfall, sunflowers did remarkably well. The 

 Mennonite and Sunrise varieties, which are considerably shorter than the Mam- 

 moth Russian, yielded less seed, but this disadvantage was counteracted by less 

 breakage of the stalks in wind storms. The wet season was very conducive to 

 weeds, yet the sunflowers had no difficulty in shading out all weeds growing in 

 the plots. Yield studies indicate that sunflowers will respond to liming. Heavy 

 fertilization of soil of good fertility tends to produce abundant vegetative growth 

 with the possible risk of lodging, especially during wind storms. 



Soil Conservation Research Projects. (Karol J. Kucinski and Walter S. 

 Eisenmenger.) 



Physical and Chemical Properties of Wind- Blown Soils. Laboratory and field 

 tests have been in progress for several years to determine why certain soils are 

 subject to wind erosion while others are not. A specially constructed wind tunnel 

 was used in the laboratory to supplement field observations. 



Climatological data were studied to ascertain what elements of climate in- 

 fluenced dust storms as they occurred naturally in the Connecticut River Valley. 

 It was found that rainfall has only a very small effect on retarding wind erosion; 

 while the months of January and February, the period of greatest snowfall, usually 

 have fewest dust storms. A direct relationship exists between known occurrence 

 of dust storms and the monthly prevalence of winds, particularly those of over 

 10 miles per hour. The data show that wind velocities increase in the after- 

 noon. This corresponds with the observation that nearly all dust storms occur 

 in the afternoon. 



In the comparison of the physical and chemical soil tests with wind tunnel 

 studies, it was found that the more sandj^ the soil, the lower was the initial 

 velocity at which it began to blow. The initial velocity was generally lower for 

 frozen soils than for air-dried soils. For most of the soils studied, the losses were 

 greater at low wind velocities for frozen soil than for air-dried soil; while at the 

 higher wind velocities, the air-dried soils were more erodible. It was found that 

 the organic matter content, the maximum water-holding capacity, the moisture 

 equivalent, and the hygroscopic coefficient of the soil had a direct relationship to 

 wind erosion. It was further noted that the higher the settling volume of a soil, 

 the lower were its losses in the wind tunnel. A ripple or wave pattern appeared 

 on the surface of sandy soils (non-agricultural) when blown in the wind tunnel, 

 while agricultural soils showed streaks. 



Soil moisture studies show that wet soil will not blow at any wind velocity. 

 The very top thin layqr of particles is relatively dry before it wind erodes, while 

 sublayers of soil may be relatively moist. Sandy soils blow sooner after a rain 

 because the capillary action is broken at the very surface of the sandy soil. 



