Amount of Topsoil 

 Removed 



% 



Yield of Hay 



Pounds Per Acre 



Unfertilized Fertilized 



Similar yield effects were obtained 

 with oats in 1945 and with corn in 

 1946. It is obvious that fertilization, 

 which included commercial fertil- 

 izer, lime, and manure, was not cap- 

 able of completely overcoming the 

 harmful effects of topsoil removal. 

 Some clues as to why this is so are 

 shown in the following table, which 

 gives some results of physical and 

 chemical analyses of soil samples 

 taken from the various plots. 



Amount of Topsoil 

 Removed 



% 



during the past seven years has been 

 12 bushels per acre greater on the 

 plots protected with winter rye than 

 on the plots which have been left 

 bare over the winter. The yield 

 benefits from the winter rye have 

 been greater during wet summers 

 than during dry summers and has 

 has averaged about 27 bushels in 

 normal rainfall years. 



With the yield benefit there has 

 also been a soil-conserving benefit 



100 



50 







These results clearly indicate that 

 the properties of the soil which are 

 commonly associated with good tilth 

 and water-absorbing capacity are 

 significantly decreased in value as 

 the topsoil is removed and hence the 

 decreased soil productivity cannot be 

 expected to be overcome by fertili- 

 zation alone but will also require a 

 building up of organic matter and a 

 re-development of better soil struc- 

 ture. The number of years neces- 

 sary for this physical process may 

 be considerable, particularly on soils 

 which have a compact subsoil which 

 is low in organic matter. 



Therefore, save that topsoil for 

 high yields this year, as well as for 

 the future. 



J. B. Bartlett 



L. T. Kardos 



from the use of winter rye. The 

 average annual soil losses from the 

 bare plots during the past seven 

 years have been almost double that 

 from the winter rye plots. The win- 

 ter rye has been effective not only 

 while occupying the ground but also 

 in rendering the soil less erosive aft- 

 er it has been plowed in and while 

 the potatoes are growing. 



From an analysis of samples taken 

 in 1947 the degree of aggregation of 

 the soil has been found to be slightly 

 greater on the winter rye plots and 

 the proportion of crumb-size aggre- 

 gates tended to be greater. These 

 properties undoubtedly account in 

 part for the decreased erosiveness of 

 the winter rye plots. 



J. B. Bartlett 



L. T. Kardos 



Does it Pay To Grow Winter Rye 

 as a Cover Crop after Potatoes? 

 The average annual yield of potatoes 



36 



Boron Needed On Some New 

 Hampshire Crops. An application 

 of boron is necessary for maximum 



