56 IOWA DEPARTMENT OF AGRICULTURE. 



and in 1902 but 48,449. The highest yield of the decade was 19 bushels 

 per acre, in 1895. In 1901 the average yield was 17.6 bushels and in 1892, 

 17 bushels. The yield for 1902 has not yet been reported, but will prob- 

 ably be heavy. The average for the ten years is 15.6 bushels per acre. 



If the acreage of winter wheat in Iowa is anywhere near correctly 

 reported in the figures above quoted, and if it has decreased as steadily 

 and as materially as they seem to indicate, it is pertinent to ask, why? 

 While a small grain crop may not be an absolute necessity to the Iowa 

 farmer, it is a practical necessity. Successful farming in Iowa or in 

 any other state or country makes it imperative that crops be rotated 

 for the double purpose of conserving and restoring fertility and to keep 

 the land in good mechanical tilth. The clovers and grasses are vital 

 in such a rotation in this state, and the study of the best nurse crops 

 for them is an important one. What will be the result of tentative ex- 

 periments with new leguminous plants, it is too early yet to know, but 

 at the present time clover is the one legume upon which the Iowa farmer 

 can depend to restore to the soil the fertility which he can remove with 

 other crops. Clover he must have, for the double purpose of forming 

 a balanced ration for his growing stock and dairy cows, and to draw 

 upon the air for the nitrogen, the most important element in plant nu- 

 trition. The question of securing a stand of clover has become a most 

 serious one throughout the state, and in considering the claims of any 

 small grain crop to recognition, its value as a nurse crop for the young 

 clover must be given much weight. 



Assuming that the clover will be sown with a nurse crop, as it is in 

 this state in ninety-nine cases out of every hundred, success in securing 

 an even and thrifty stand will depend largely upon: First, getting it 

 in early and covered pToperly; second, giving it a sufficiency of sun- 

 light; third, getting the nurse crop off the ground before the hot days 

 of July. Winter wheat enables these requirements to be fulfilled as well 

 or better than does any other small grain crop. First, it is sown in the 

 fall, and the clover can be sown at any time during the fall, winter or 

 spring, at pleasure, preferably on the last snow in the spring. It can be 

 harrowed in, if thought desirable, without injury (usually with positive 

 benefit) to the wheat, if the ground be not too wet. Second, the wheat, 

 if drilled in north and south as it should be, gives the sunlight oppor- 

 tunity to reach the young clover plant nicely. Third, the wheat is har- 

 vested early, and as it stands up well the clover suffers little injury by 

 the change from shade to sunshine. As compared with oats, winter 

 wheat is very much superior as a nurse crop. The oats cannot be sowed 

 until the ground is fit to work in the spring, and as a result the clover 

 is not sowed for from one to three weeks later than with wheat. It not 

 infrequently happens that it is not properly covered, owing to frequent 

 spring rains between the time the oats is sowed and the clover, and even 

 when covered sufficiently to germinate, the field is often left rough for a 

 meadow because of the impossibility of getting onto it with a harrow. 

 The oats makes a denser shade than the wheat, thereby increasing the 

 danger of smothering the clover; it is much more likely to lodge, espe- 



