THIRD ANNUAL YEAR BOOK — PART VI. 



283 



growth it must have light and heat above as well as moisture below, and 

 just here is where most farmers fail. They sow clover with a "nurse 

 crop," so-called. That nurse crop, generally oats or spring wheat, is a 

 rank grower and so shades the ground that the plant cannot have sufficient 

 light. The leaves of the plant can't do their work in darkness. The 

 growth is made through the leaf by taking up the carbon dioxide, or as it is 

 generally called, the carbonic acid of the air, dissolving it by means of its 

 green coloring matter, exhaling the oxygen and using the carbon to build 

 up the plant, for this is absolutely necessary. Unless it gets light and 

 plenty of it. the plant can't grow, and just in proportion as the nurse crop, 



Group of Short-Horns, winners of the Grand Beef Herd prize at Iowa State Fair, 

 1902. Owned by G. M. Casey, Clinton, Missouri. 



so-called, shuts off the light, just in that proportion does it weaken the 

 clover plant, the weakness being shown by the lack of color in the ieaf. 

 Therefore if you use a nurse crop, use one that grows as slender in the 

 stalk as possible, with as narrow a leaf as possible, and that matures as 

 early as possible. It is for this reason that we advise sowing the earliest 

 kind of every kind of spring grain whether wheat, oats or barley, when used 

 as a nurse crop for grass seeds. The reason why so mnay farmers succeed 

 in getting a stand of clover when putting it on rye or winter wheat or 

 cats and using these as grasses, is because the constant cropping of the 

 grass by the cattle keeps down the "strangling crop" (for that after all 

 is the true name of the nurse crop so-called), and permits the young plants 

 to have the light they so much need. Weeds act in the same way, and the 

 only reason why we sometimes recommend sowing some kind of grain 

 with clover when the land is very foul instead of giving it the full use of 



