A Salisbury resident emailed me last week and was concerned about his oak trees. They were doing quite well but had no acorns for the past two seasons. He was wondering if there was a problem with his trees. There are a few situations that will cause oak trees not to produce nuts. Environmental and weather conditions are an important factor in acorn production. When oak trees bloom in the spring, they are often subject to uncommon weather conditions. The flowers of oak tree species are diecious type meaning the male and female parts are separated but located nearby on the same tree. Female and male flowers may not mature at the same time to pollinate. The female flower is very small and are only fertile for a short time in the spring, sometimes only for a week. If there is a weather problem such as a late frost or heavy rainfall during the fertility period, the fragile bloom may be damaged or destroyed and there will be no fruit. Poor pollination is a common problem with many species of oaks pecan and other trees. It can vary from one tree to another or one area or another. It just depends on the time of year and tree’s condition. Extreme temperature fluctuations, droughts and flooding have a tremendous influence on the overall health of the tree also a basis for poor acorn pollination and premature acorn drop.

Darrell Blackwelder is the retired horticulture agent and director with the North Carolina Cooperative Extension Service in Rowan County. Contact him at deblackw@ncsu.edu .