October through mid-November is the typical flowering time for Witch Hazel. The last of the blossoms of this fall-blooming shrub can still be seen in parts of the Northeast. Its long, bright-yellow petals and the presence of a sweet-smelling nectar tell you that Witch Hazel flowers are pollinated by insects. However, there are very few insects present this late in the year and its pollinators have been elusive to the human eye. With the exception of syrphid, or hover, flies, I have never seen any insects visiting these flowers.
It turns out that I was observing them at the wrong time of day. Naturalist Bernd Heinrich discovered that a group of owlet moths called winter moths are active on cold nights and regularly visit Witch Hazel. These moths have the ability to heat themselves by using energy to shiver, raising their body temperatures by as much as 50 degrees in order to fly in search of food. Solved is the mystery of what pollinating insects are still active this late in the year!
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