Hickory and some oak species have gone nuts this year and produced a bumper crop of nuts and acorns.
Foresters say that it's tough to pin down a reason, and that a combination of factors might be at play.
Jim Brandle, a professor of forestry at the University of Nebraska-Lincoln, offered a couple possible explanations:
» Trees goes through cycles of productivity. Some years, they produce a lot of fruit, other years not so much. For these species, this could be their productive year.
• This spring was cool, wet and lacked a late freeze. As a result, a greater percentage of the flowers on trees were successfully fertilized, which meant that more flowers were able to mature into nuts and acorns. A poorly timed late freeze would have prevented some flowers from being fertilized. And the species that are productive might be more partial to cool, wet weather than the ones that aren't as productive.
• Last year's extreme drought might have cued the trees to put out a greater quantity of seeds this year. When trees are under stress, they sometimes respond by producing more seed as a way of continuing the species.
“There are so many things that could come together, it's impossible to be certain exactly why this is happening,” Brandle said.