Ladino clover, smooth brome grass. Kentucky bluegrass and bentgrass were grown in greenhouse pots to determine the relative uptake of K by the species when grown separately, and to study the competition for K when Ladino clover was grown in association with each of the three grasses. This was to determine to what extent the theory of differential cation uptake by plants of different root cation exchange capacity can explain the disappearance of legumes from pasture mixtures as a result of plant competition for K. Potassium uptake by plant species at low levels of soil K was closely correlated with root cation exchange capacity. The relative K compatibility was smooth brome (best). Kentucky blue (intermediate) and bentgrass (poorest). Because of the strong attraction and high uptake of K by roots of bentgrass, it was impossible with practical rates of K fertilization to maintain an adequate K supply for the associated Ladino clover.
No takes yet. Share an insight, caveat, or question.
Gray et al. (1953) studied this question.