Clover commands a peculiar place in the agriculture of Iowa. It, above all others, is the legume that is used by stockmen for the production of cheap protein; that fits into a systematic rotation of crops perfectly; and that undoubtedly is the best legume to use in this state for increasing the nitrogen and humus content of the soil. All of these demands are met by red clover, trifolium pratense. But at the present time, from the standpoint of acreage and value, clover is distinctly a secondary crop. It should be more extensively grown throughout the state, and no doubt a larger acreage will result when the waning fertility of our soils makes evident the need of careful and systematic farming.
Alfalfa seems peculiarly adapted to the West, but it is not as yet sufficiently well suited to Iowa conditions to supplant clover. Cowpeas and soy beans are valuable crops farther south where clover can not be grown, and they doubtless have their place as catch crops in this state.
Stevenson, W. H. and Watson, E. B.
"Clover growing on the loess and till soils of southern Iowa.,"
Bulletin: Vol. 9
, Article 1.
Available at: https://lib.dr.iastate.edu/bulletin/vol9/iss98/1