Reply to post by Mike Campbell, on May 27, 2003 at 17:53:48:
There are male tree cultivars, but there is a warning at the following linked site about some that were introduced as males but turned out to be late-flowering females. No names were given. Deal with well-established nurseries and research male cultivars and get a guarantee of the tree's sex. If you already have a tree in the ground but don't know its source, then you basically have to wait, I think.
Someone planted many Ginkgo trees at Chico State campus 25 or 30 years ago, and most of them turned out to be females. Most of those have been removed, finally. Over the years I noticed some generalized things about the differences between male and female trees. Females tend to have sparser foliage and a lighter color of leaf, almost a yellow-green rather than bluish-green. Females also seem to tend towards leafing-out a bit later and defoliating earlier than males. Also, the largest Ginkgo trees I've seen have been males, although variables such as quality of individual rooting area, quality of planting stock, exact age, etc. are unknown.
