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Show 7 Local Soil Scientist Writes Last of Articles 5 to Of ntv The Nitrogen Problem of Sanpete Countv Soils ' ' By MltKOM MAKCIIAXT, Soil Scientist 'Cil Soil Conservation Service, Mt. l'lciistmr ere -tic Nitrogen in tlu soil is very closely associated with tlic ich organic and hioloyical life of tlie soil. 1 lie plants use nitrogen in the form of initrate nitroo'en. i They obtain this from manure, or- panic matter, or it can bo directly applied as a commercial fertilizer ete in the form of ammonium sulfate. The only organisms that can 9t assimilate and use the inert at- W'tl mospheric nitrogen of the air are the nodule forming bacteria found i in the roots of alfalfa, peas, and "I other legumes. If enough niois- S a ture and organic matter are pres ent for these bacteria to use as a source of food and energy, they will "fix" additional nitrogen from )Up the air. This element forms a part of the bacteria and upon the completion com-pletion of the cycle., the bacteria erg die and the nitrogen in combina- er tion with oxygen, becomes avail- , able as plant food. This is a very delicate relation-to relation-to ship which can be seriously inter fered with by many seemingly unimportant un-important items. Some of these id, items are: Addition of too much jjj water (over-irrigation for too long a period) ; low soil temperatures "5 during the growing season, or the ; j lack of organic matter. The pres- ence of large amounts extremely 1 coarse fiberous crop residue, or manure with large quantities of )up straw bedding included will also i depress yields of crops sensitive to ' lack of nitrogen. All or any one of the above con-ditions con-ditions will adversely affect the carbon-nitrogen ratio of the soil i si- and result in temporarily de- creased yields. The best source of nitrogen, though it may be limited, is barn- !3I yard manure. No farmer is on safe economic gs ground who buys commercial ni- trate fertilizers and who does not fully utilize all available barnyard manure. en We have no quarrel with com- r a' mercial nitrate fertilizers, they are en useful and desirable if used not to replace manure, but to supplement it. As previously stated, nitrogen is a very unstable element in the y soil. It is not practical to build im I up and store any large amount in da - the soil for future use. One should il- try to achieve a- supply and bal- T.e ance of the nitrogen liberating -'.' agents. This will assure a con- e tinuous process of releasing nitro- gen for the plant. he k Soil tests for nitrogen contents are not reliable unless made re-1 thruout the growing season. The most practical method of peatedly over a period of time farming is to build up the organic content of the soil to a point where one is assured of an adequate supply sup-ply of this element at the right time for the plants' needs. This can be achieved thru crop rotation, use of barnyard manure, green manure and the use of commercial com-mercial fertilizers as a supplement. supple-ment. Sweet clover, vetch, and other crops turned under when gTeen will furnish excellent results as a green manure. Another practice is to plow under the last cutting of alfalfa at the end of the rotation. One handicap of green manures in Sanpete is that farmers are j loath to turn under a potential . crop of fodder. Many feel that they need the feed more than the fertilizer. This if often true, but in many instances it is jumping over a dollar to pick up a dime. The benefits of the green manure will more than compensate for the sacrifice of the one cutting of hay. |