Show important place for legume crop ftp rdo not improve soil unless many conditions are first right legumes Leip imet have have had an important place in crop production for many centuries no doubt one of the chief reasons for the treat great popularity of 0 this class of crops to 18 the fact that thai under suitable conditions condl tlona they bay have hare a very desirable influence upon he crops which follow them the increased corn yields following the use of a clover clorer crop as a green creed manure to the worth of legumes for soil loll bullying purposes soil improvement the idea vt of soil improvement in 18 so BO frequently associated with the term legume that one often overlooks the fact that all legumes tire are not equally effective for this purpose according to 0 H sears assistant chief of soil biology at the college of agriculture university of illinois As a matter of fact act legumes not only differ in their ability to improve crop yields but they hey may at times even eren have a tendency to lower the fertility of the soil eoll the extent to which legumes are valuable in soil improvement will depend upon a treat great many conditions one of these conditions Is inoculation legumes are considered soil build ing crops primarily because they have access to atmospheric nitrogen pro their roots are well supplied with nitrogen gathering bacteria living within the nodules on an the roots of the plants such plants aro are said to be inoculated inoculated legumes thus may secure their nitrogen from the inexhaustible supply of the air it if not inoculated however legumes leg umon like other kinds of plants must depend upon tile the soll oll for their nitrogen BS as well UK am their ini miner il requirements and since they art hoaby feeders upon nitrogen and other plant food elements they may be the most effective of soil boll fertility grown on the lie farm to function as soll soil building crops legumes must therefore be inoculated benefits derived the method of utilizing the crop Is in another important factor in determining the benefit to be derived from the growing of a leguminous crop under tile the best conditions even inoculated legut nes secure only apart a part of 0 theli nitrogen requirements from the air approximately a third of the nitrogen found in the lie legume plants comes front from the soll it Is apparent there foro that the soil roll content of this lin ill elen element tent call be In creasea only by returning ft A portion of the plant to lie soil in ili tile form forill of roots stubble residues and as aa green ir r stable na ma A larger proportion of tile tops must bo be returned in ili the caso of sonn leg unies thau than Is necessary wath others nine tenths of the soybean soy so bean plant la IA contained within the tops while about one half the alfalfa plant Is below tile the ground thus rp wing li if lie whole soybean soy bean ij 11 and returning nothing in fit the way of manure or threshed straw would tend to deplete tile the soil aoh even though the planta w wre vre re inoculated whereas the removal of n crop of alfalfa would have anve a much less serious effect soil improvement can be accomplished therefore by returning a major portion of inoculated legumes to the lie soil in one form or I 1 another |