Jun 23, 2025
In the eastern part of their range, Columbia silk moth caterpillars hatch from tiny eggs, laid on hackmatack (aka tamarack, aka eastern larch) trees. This deciduous conifer, common in the northeast, is the primary food source for these caterpillars. After their cocooned over-winter transformation to a moth, they no longer eat or drink. They’ve only got a couple of weeks on the wing to find a mate, and lay eggs on another larch. Late may to early July is the best time of the year to spot one of these large moths, as well as their cousins, cecropia and luna moth. So double check the side of your house if you forget to turn off the outside light this week.
