The American Chestnut Foundation - Field Guide to the American chestnut tree

The American Chestnut Foundation - Field Guide to the American chestnut tree:

Field Guide for locating, pollinating, and harvesting
nuts from flowering American Chestnut Trees

Pollen testing - It does you no good to pollinate your tree with dead pollen. It is best to test pollen if possible. It may be advisable to test it every day or so during the pollination season. Chestnut pollen is easily germinated if floated on drops of 1% table sugar (or glucose) in non-chlorinated water, and held at 85°-90° F for one hour. Examine under a microscope at 30-100x magnification. Good pollen should show 15-60% of the grains with tubes (as long as the grains) growing out of them.