THIRTY-FIFTH ANNUAL CONVENTION. 233 



even when the crop is havested for hay or seed increase in soil 

 nitrogen will result from the decay of the roots left in the soil. 



In most soils of this state nitrogen is the limiting element 

 of fertility, and anything that will increase the nitrogen supply 

 of the soil will increase the soil's productiveness. The cow- 

 pea, having this ability to secure nitrogen from the atmosphere, 

 not only produces more abundantly than a crop not having this 

 power, but leaves the soil in better condition for crops which 

 follow. 



Mr. H. T. Neilson, of the United States Department of Ag- 

 riculture, in Farmers' Bulletin No. 318, in speaking of the effect 

 of the cow-pea upon the following crops, says : "The increase in 

 yield of wheat due to the cow-peas is generally given as from 

 three to five bushels per acre. At the Missouri Experiment Sta- 

 tion, an increase in yield of 63 per cent, with oats and 49 per 

 cent, with wheat following cow-peas as a catch crop was secured. 

 The Arkansas Experiment Station reports, as an average of four 

 years' test with wheat, an increase in yield of 25 per cent, from 

 plowing under cow-pea stubble in the fall, 39 per cent, from 

 plowing under cow-pea vines, and 42 per cent, when cow-peas 

 were grown each year as a catch-crop between the wheat crops, 

 only the stubble of the peas being plowed under." 



At this Station we have sown cow-peas as a catch-crop be- 

 tween the wheat crops for the past five years, plowing under 

 the entire growth of peas about the middle of September, two 

 or three weeks before seeding to wheat. The cow-peas have been 

 sown each year soon after wheat harvest, in close drills, at the 

 rate of about one bushel of peas per acre. The field was usually 

 double-disked ahead of the drill. Both plots were plowed on the 

 same date and given similar preparation before seeding. The 

 field used for this work was upland soil low in fertility. The 

 yields for the past five years are given in table II. 



Each season the catch crop of cow-peas has given an in- 

 creased yield of wheat and the effect has been accumulative, the 

 increase in yield being gradual from year to year. The first year 

 of the trial there was a difference of only one bushel in favor of 



