Individual pods sometimes yield over 30 seeds, and in rare instances over 40 seeds. It is not known what opportunities exist to raise seed yield through more seeds per pod, or whether an increase in seeds would be offset by compensatory losses in other components of seed yield. Honeybees are the best, leaf-cutter bees the next best, and bumblebees the least effective pollinators of trefoil. Honeybees visit 10 to 12 florets per minute, and a floret may receive 12 to 25 visits if bees are abundant in the four to five days it is open. Pods are mature about four weeks after pollination and dehisce shortly thereafter if relative humidity is below 40 percent.
Seed production varies greatly from place to place and year to year.
Other areas fall within these ranges. However, yields in any one year may vary from a low of 5 pounds to a high of 500 pounds per acre. These conditions occur often, and we can relate them to yield components more easily than the other conditions. Often when flowering is severely depressed, pod set and seed set per floret decline also. The ability of trefoil to produce cyclic flushes of bloom from new growth from stem axils or crown buds, depending on the variety, is another complication in assessing seed potentials.