 Most commercial cultivars are hermaphroditic; cultivars that produce only functionally female flowers require the presence of male trees.Male trees are seldom found, as vegetative selection has favored hermaphroditic clones that produce a high proportion of functionally female flowers and a much lower number of flowers that produce pollen.Over 3,000 greenish-white flowers occur in male panicles, each with five to seven anthers and a nonfunctional ovary.