Determining by plant response the retention of nutrient ions by soils
Conrad, J.P.; Adams, C.N.
Journal American Society Agron 31(1): 29-34
By allowing a soln. containing an essential element to drip upon a column of pots of dry soil responding to that element, the retention or non-retention of the element in question may be judged. After percolation has ceased, the column is taken down and the pots subsequently cropped to milo. In different tests the retention of ammonium and phosphate ions was shown by the markedly increased growth of the top pot of each column. The pots in the columns to which nitrates, nitrites, and sulfates were added showed non-retention by the rather uniformly enhanced growth in all pots of the respective columns. The method shows promise in research as well as in teaching.