Interspecific competition between seeds: relative planting date and density affect seedling emergence

For Senecio vulgaris and Poa annua, probability of emergence significantly decreased with an increase in total seed density. Neither the density of conspecifics nor heterospecifics alone could explain this decline in the probability of emergence. For these 2 species and Capsella bursa-pastoris the rate of emergence accelerated in the presence of previously planted seeds. This acceleration involves a response to leachate from previously germinated seeds. -from Authors