THE ASSOCIATION OF FLOWERING HABIT WITH WINTER SURVIVAL IN RED AND ALSIKE CLOVER DURING THE SEEDLING YEAR OF GROWTH

Abstract

The percentage of plants that flowered in the seedling year in spaced populations of red and alsike clovers at Madison and Arlington, Wisconsin, was highest in the earliest seedings (May 15) and decreased with later seeding dates. No plants flowered in the July 15th seedings. The percentage of winterkilling during the first winter was higher in the flowering plants of each clover than in the non-flowering plants. Differences in flowering and winter survival were noted among clover strains and in winter survival among plant types within strains.Prevention of flowering in medium red clover by removing flower buds, flowering stems and/or elongating tillers resulted in greater vegetative vigour and winter survival. Plants that were allowed to flower freely in the seedling year in spaced populations had a smaller number of non-flowering crown tillers, a smaller width of crown, a lower dry weight of crown, root and total available carbohydrates in the roots, less root branching, a slightly lower percentage of total available carbohydrates in the roots, and more winterkilling during the first winter than plants that were prevented from flowering. These responses may help in part to explain the benefits attributed to clipping red clover in the seedling year.