There is much evidence that chestnut pollen is largely carried by
insects although this has not been fully established. The Chinese
chestnut is largely, although apparently not wholly, self sterile; more
than a single seedling or grafted variety should be included in any
planting. Several seedlings or several varieties would be better. In
seedling plantings, all trees that produce inferior nuts should be
removed in order to avoid danger of undesirable pollen influence,
either on nut characters, or on the genetic makeup of the embryos if the
nuts are to be used as seed.