CORN, WHEAT, OATS, BARLEY, RYE 79 



best plants for green manures. It grows well in the soils most 

 in need of assistance and is very hardy. As a pasture it can be 

 used both in the fall and in the spring. It can also be used 

 effectively as a soiling crop. 



Rotations for small grains. — The advantages of a crop rota- 

 tion over continuous culture have already been given under 

 corn, likewise a short list of standard rotations. Therefore, 

 they need not be repeated here. Barley and rye do not appear 

 in the rotations, but barley may be substituted for oats and rye 

 for wheat in any of the rotations where it seems to be desirable. 

 Like^^dse rye may be used in practically all rotations as a catch 

 crop to be plowed under for a green manure. 



Small grains practically always follow inter-tilled crops 

 regardless of the rotation. There are good reasons for this 

 practice, as follows: 



(1) The inter-tilled crop helps to prepare the soil for the 

 small grains. 



(2) Small grains are more delicate feeders than tilled crops 

 and consequently cannot take advantage of coarse manures and 

 organic matter. 



(3) Small grains can endure a more exhausted soil than tilled 

 crops. 



(4) Permits of equal distribution of farm labor. 



(5) Land is kept more fully occupied with crops. 



(G) Small grains serve as nurse crops for grass and clover. 



The matter of the place in the rotation of any one crop is 

 not so important, however, as the matter of rotating. 



Rotation of crops is absolutely essential to an economic system 

 of maintaining soil fertility. 



Improvement of small grains. — The same methods are avail- 

 able for the improvement of small grains as for corn, namely : 

 introduction, selection and hybridization or crossing. 



Until the present time, introduction in the case of small grains 

 has been far the most important in the Ignited States. This 

 is naturally to be expected since the small grains were groAMi 

 hundreds and in some cases thousands of years in Europe 

 under very diverse conditions before America was discovered. 

 During that period many varieties with special adaptation were 

 developed, many of which have been introduced into this coun- 

 try and have immediately come into prominence in regions 

 similar to the region from which they were introduced. Sev- 

 eral agencies have played an important part in the introduc- 

 tion, namely. United States Department of Agriculture, seed 



