278 IOWA DEPARTMENT OF AGRICULTURE. 



1,090 pounds of straw and 7 bushels 2 pounds per acre. On the plot on 

 •which Banner oats had been sown with clover in 1897 there was an addi- 

 tional yield of 2,850 pounds of straw and 10 bushels 30 pounds of oats. 



The reason for the small increase in two of the plots was because the 

 land was of much inferior quality as compared with the others. The re- 

 sult of these tests show that the average yield of grain on the four plots 

 with clover exceed by 11 bushels one pound per acre the yield of those on 

 which no clover was used. Bear in mind that this is what we call one- 

 crop clover, sown in 1897 and turned under in the fall. 



The next year these plots were again sown to Mansury barley. With- 

 out going into details it is enough to say that the average increase the 

 second year over plots of the same character that had not been sown to 

 clover in 1897 was 8 bushels 31 pounds. On this the station comments as 

 follows: 



"These results are indeed remarkable. They show in the case of the 

 plots under consideration that the plowing under of a single crop of clover 

 sown with the grain in 1897 produced a wonderful increase both in straw 

 and grain. The crop of straw when compared with the adjoining plots on 

 which clover had not been sown was increased 78 per cent in 1898 and 35 

 per cent in 1899. The grain was increased 28 per cent in 1898 and 29 per 

 cent in 1899." 



In 1899 the station plowed a field of four acres four inches deep. The 

 soil was a sandy loam of medium quality. On two acres of this land bar- 

 ley had been sown in the spring of 1898 and with it ten pounds of clover 

 seed. One acre had been in brome grass. Half an acre had been sown to 

 a mixture of pasture grasses with clover and half an acre to a mixture 

 of pasture grasses without clover. It was sown to Bavarian oats with the 

 following result: 



The acre of oats after brome grass yielded 33 bushels, 8 pounds. The 

 half acre after pasture grasses without clover yielded 36 bushels, 16 

 pounds; the half acre after pasture grasses with clover 46 bushels, 4 

 pounds; the half acre after pasture barley with clover yielded 43 bushels, 

 28 pounds, or a difference of 10 bushels, 4 pounds per acre in favor of the 

 crops grown after plowing under clover. 



A similar line of experiments were conducted in the year 1900 with 

 the following results: The crop grown was New Zealand oats. The in- 

 crease in the yield after wheat with clover was 1 bushel 52 pounds; after 

 barley with clover 2 bushels 12 pounds; after oats with clover 2 bushels 

 '(2 pounds per acre. On this the station comments: 



"This yield was the smallest at any time obtained where clover had 

 been plowed under and was probably due in part to the fact that the grain 

 with the clover was sown a week later than usual and the subsequent 

 growth of the clover was light and unsatisfactory." 



A similar line of experiments in plots continued in the year 1901. 

 There were six plots in number, two sown with wheat, two with barley and 

 two with oats; and one of the plots in each case sown with clover and one 



