100 Species #50: Spring cankerworm
May. 15th, 2011 12:15 pm![[personal profile]](https://www.dreamwidth.org/img/silk/identity/user.png){kind=small}
urbpanEDIT: THIS IS ACTUALLY THE CATERPILLAR OF THE WINTER MOTH, WHICH APPEARS AT ENTRY 100.
Spring cankerworms (Paleacrita vernata) seem to use humans as a larva dispersal method. This photo was not taken in the yard, but the caterpillar originated there, and was transported to work on my sweater.
This week you can't walk in my yard, or anyplace with trees in eastern Massachusetts, without encountering an inchworm dangling on silk. It may hang there in the air, fall on your clothes, or become entangled in your hair. These little caterpillars aren't really trying to land on you, but there are so many of them, that it's almost inevitable. They hatched from eggs glued to the trees a few weeks ago, and set upon the task of defoliating the new leaves as they unfurled. Don't worry about the trees--the hardy ones will produce new leaves to replace the ones skeletonized by the cankerworms. The sudden irruption of this species and others is important fuel for the spring bird migration.
This species is amazingly variable, from pale green to brown to almost black, many but not all individuals sporting a longitudinal stripe. They descend on silken threads and may be blown to another edible plant--almost any of our commonly planted urban and suburban trees including apple, birch, maples, and oaks. Eventually they descend to the ground, and burrow in to pupate, emerging some 10 months later. Females are wingless, like winter moths, and crawl up tree trunks to find a place to lay eggs; males have bushy antennae to detect the scent of the females, and wings to carry them there. The adults are small moths the color of tree bark.
Spring cankerworms (Paleacrita vernata) seem to use humans as a larva dispersal method. This photo was not taken in the yard, but the caterpillar originated there, and was transported to work on my sweater.
This week you can't walk in my yard, or anyplace with trees in eastern Massachusetts, without encountering an inchworm dangling on silk. It may hang there in the air, fall on your clothes, or become entangled in your hair. These little caterpillars aren't really trying to land on you, but there are so many of them, that it's almost inevitable. They hatched from eggs glued to the trees a few weeks ago, and set upon the task of defoliating the new leaves as they unfurled. Don't worry about the trees--the hardy ones will produce new leaves to replace the ones skeletonized by the cankerworms. The sudden irruption of this species and others is important fuel for the spring bird migration.
This species is amazingly variable, from pale green to brown to almost black, many but not all individuals sporting a longitudinal stripe. They descend on silken threads and may be blown to another edible plant--almost any of our commonly planted urban and suburban trees including apple, birch, maples, and oaks. Eventually they descend to the ground, and burrow in to pupate, emerging some 10 months later. Females are wingless, like winter moths, and crawl up tree trunks to find a place to lay eggs; males have bushy antennae to detect the scent of the females, and wings to carry them there. The adults are small moths the color of tree bark.
