Removal of plant food in thinning corn
1926
Davidson, J.
Corn seedlings removed during two successive thinnings were analyzed to determine their content of nitrogen, potassium, and phosphorus. The pulled-out corn seedlings removed considerable quantities of nitrogen and potassium from the hills, but left behind small quantities of the phosphorus originally contained in the seed. During the week between the first and second thinning about twice as much potassium and nitrogen was absorbed by the corn seedlings as during the period between planting and the first thinning. Nitrates and ammonium salts were present in the young corn seedlings in appreciable quantities. The application of sodium nitrate and ammonium sulfate increased the absorption of nitrogen, potassium, and phosphorus by the seedlings consistently during the period between planting and the time of the first thinning, but this effect became less pronounced a week later at the time of the second thinning. The importance of prompt thinning and of avoiding overplanting is emphasized.
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