Flighty Oaks. In the National Arboretum's parched herbarium, where dried plants date to the 1790's, Alan Whittemore is providing needed acorn perspective. A year after few fell in parts of the U.S., the botanist says hungry squirrels and an anxious press--which breathlessly wondered, Is it climate change?--can relax.
Oak trees, he explains, don't have regular cycles or produce big harvests every year. Factor in weather--cold, wet springs impair pollination; hot, dry summers hinder maturation--and you've got acorn variability.
UCLA biologist Victoria Sork concurs. Back in the 1980s she tallied two near-zero year in eastern Missouri. The next fall? A bumper acorn crop. "We have to be careful about reading too much into one year," she says.
Meantime, says botanist Rod Simmons, the next boom year will be a boon year for all. One huge oak can drop up to 10,000 acorns, so well-fed squirrels are likely to heard and forget their leftovers--and thus plant trees far and wide.