Seeds of Melilotus alba and M. officinalis were sown in four different—sized openings in Canada bluegrass, a dominant of an old field. A relationship between seed germination and size of opening in the sod was not apparent but early seedling survival was correlated (P<.01) with size of opening, the larger openings yielding a greater number of viable seedlings. The areal extent of the dominant plant in the old field thus appears to regulate the number of sweetclover plants at an early stage of their life cycle.