Show DIET deficiency CUTS CROP YIELD lack of essential foods reduces productivity by HERBERT L GARRARD diagnosing the ailments of sick crops and prescribing the restora tives is a science that can t turn urn losses into profits on amer american can farms many of the destroy the productivity of crops are d due ue to diet deficiency elenc y to a lack ot of such essential plant foods as nitrogen phosphoric acid and potash in the soil and just as telltale tell tale symptoms are present when human beings are ill so growing plants reveal their infirmities by various signs even in the early stages of growth these signs of ill health are readily discernible sickly seedlings with narrow leaves thin stalks poor root formations and tips ot of leaves tinted a reddish brown hue tell a story ot of starvation for necessary plant nourishment ish ment with oats tor for example a deficiency ot of potash in the soil will be evident in a reddish coloration of the leaves as early as eight days after sprouting the foliage of potatoes shows a dark green in the early stages of potash starvation in in the case of tomatoes there is a purplish leaf coloration when the plants are starved for phosphorus corn that is suffering from diet deficiency is easily recognizable when nitrogen is lacking it develops a streaked yellow leaf when potash is missing the edges of th the e leaves are fired or scorched and a spotty yellow streaking cpr spreads eads over them fortunately it is possible even in the growing season to apply correctives fec rec tives once the ailment has been diagnosed tests in corn belt states have proved that with corn still in the early stages of growth it is possible to side dress the plants with fertilizer to correct dietary deficiency the use of pounds per acre of mixed fertilizer containing potash in early july on 15 cornfields on a soil high in lime content in a midwestern state resulted in an increase of bushels per acre compared with fields not treated for potash starvation but while plant food deficiencies can sometimes be corrected during the growing season the sure preventive is to have the soil tested before planting time county agents or agronomists at the state agricultural college are prepared to analyze soil samples and provide farmers with information concerning the fertilizer needs of their soil the tests will reveal whether there is is a lack of nitrogen phosphoric acid or potash by following the recommendations ions thus obtained farmers can replenish depleted soil resources and be reasonably sure of growing healthy productive crops |