Why does the Loring Greenough witch hazel next to the fence by South Street open its thread-like bright yellow blooms in the frigid temperatures of mid-February, when there are no pollinators about? Bees and butterflies do not fly when temperatures fall below 55°…
This question intrigued University of Vermont biologist Bernd Heinrich, the author of the popular nature study Ravens in Winter. He could see no pollinators around nearby witch hazels in bloom in late winter when he inspected them during the day. So he stole out at night in icy Northern New England temperatures with a flashlight. To his astonishment, he found inconspicuous brown owlet moths feeding on the nectar. The moths are capable of shaking themselves out of their winter torpor by shivering until they are warm enough to fly. They apparently evolved together with witch hazels to have this symbiotic relationship.
The side benefit to the garden lover is that something this bright and cheery blooms so early as a promise of spring. The similar yellow forsythia, for which many people mistake witch hazel, does not normally bloom in New England until early April.
Come enjoy a walk around the Loring Greenough grounds and see if you can find the two yellow witch hazels, along with white snowdrops starting to poke out of the ground!