Show GREEN ONE OF OLDEST METHODS USED TO IMPROVE SOIL ix n 4 11 11 r J red clover ranks high in importance among leguminous crobu although green Is one of the oldest methods used to maintain or to increase the productivity of the soil there have been enough new developments in the practice and in the plants used for the purpose in recent years to make desirable the publication by the united states department of agriculture of farmers bulletin 1250 green by C V riper piper end and A J Pl cleters eters the subjects discussed range from arora a definition of the term green means the turning under of any crop while green or soon after ripening tor for the purpose of soil improvement pro to descriptions of the many crops that are used for land betterment in most regions of the united states and in some other countries the use usa of special green manure crops says the bulletin Is much more general in the south than in the north in the semiarid semi arid regions tor for reasons made clear under dry farming green manures are not used but in irrigated areas in the west depend upon them to a great extent to increase Inci ease the yield of fruit crops benefit soil these crops that are grown primarily as roughage tor for feeding the soil produce both chemical and physical effects that are of benefit to plants that succeed them when a green manure crop Is turned under the various fertilizing elements that ha have hae e gone into the making of the crop are returned to the soil and a quantity of organic matter not before in the soil Is added and in addition to improving the physical condition serves as food for beneficent bacteria one of the most I 1 important functions of organic matter in the soil Is to keep up the nitro nitrogen geu supply the bulletin gives three ways in which this is done 1 growth of nodule bacteria on roots of leguminous plants 2 the making of nitrates by soil bacteria from organic nitrogen in ili the roll eoll and 3 growth of bacteria and molds that teed feed on plant waste naste in the soil and take nitrogen directly from the air these processes may be stimulated by adopting the proper practices and suitable crops satisfactory cover crops crop legumes are of course the most satisfactory cover crops under most conditions and all legumes do not have the same strain of nodule bacteria for instance that of clover Is different from that of alfalfa and that of the cowpea Is distinct from that of the soy bean these selective tiNe associations of plants and bacteria make inoculation of the soil necessary where the crop has not been previously y grown either by scattering soil from a field where the crop to be sown has been grown recently or by using an artificial culture A strain of bacteria will often inoculate differ 6 A 6 l 1 f i 4 1 I A field of soy beans a good home grown feed rich in protein and excellent for dairy cows ent closely related le legumes guines alfalfa bur clover find and sweet clover nodules are produced by the same strain a different train strain inoculates most of tile detches vetches vet clies ches its as well ieli ns as the field and gaiden peas still another strain lg Is apparently used in common by red nl al slice and crimson cloi clovers ers the question oft often n arises whether a crop should be turned under fur for green manure fed on the faim or sold belil as hay bay the authors sum sain up the argument its as follows where a forare forace ci cina op can bo be grayed or advantage advant advantageously ag foil fed and the manure returned to tile he lani land this will be most profitable whore insufficient live stock Is heit or where the soil Is poor and in need of organic matter a preen green crop way may often be worth more if turned under lt it la 19 known that the turning under of a green manure crop may effect the yield of subsequent crops even to the lie third bear ear and this tact fact should bae weight when the question of selling a legume liny bay crop or turning it under Is considered A regular farm practice green in some furm form should be part of the regular farm practice prattled on most of the farms east of the hundredth meridian and on irrigated land elx where rotations should be arranged so as to in a green manure allure lu crop between regular crops without sacrificing direct money or feed crops preference should he be given to a legume it if possible the value of these crops Is determined by the quantity of humus formed measured by the tonnage of the crop the physical changes brought about in ill the soil and the quantity of nitrogen taken ken froni from the air and added to tile the soil there are probably other factors that are as yet but bui little understood it Is said that green manure in orchards checks certain diseases and improves the quality of the fruit order of importance the leguminous crops grown in this country listed in the bulletin I 1 in n order of importance are red lied clover alfalfa alslee clover sweet clover cow pens peas peanuts sy soy beans velvet beans m 41 4 1 kiy Q y br A aws sy i i wy I 1 3 W Z y 1 I 1 ill t e t N 6 A R 1 W ON P M 4 1 an excellent stand of alfalfa crimson clover field peas vetch japan clover bur clover and white clover A few others such as grass peas fenugreek and horse benna beans are grown to a small extent in restricted strict ed localities non crops that are considered as useful green manures manure are grasses buckwheat weeds needs and some plants of the mustard family that are used more in europe than in this country the bulletin contains more than 40 pages of valuable information ont on these liese I 1 plants and the ways of handling them also tables of results that show their value in lu increasing creasing Ore returns turns A copy may be obtained free by addressing the department of agriculture wash ington D C |