Monday, September 28, 2009

Tent Worms vs Woolly Bears

Can't have my woolly bears maligned, so here is some info regarding the two different creatures. The tent caterpillars are the nasty destructive ones and I remember them dripping from the trees, landing in my hair or going down my collar. Very unappealing. That said, I don't really want a woolly bear walking about on me either--prickly little feet!
How could we ever be bored? I greatly enjoy the discussions and the curiosities raised by our respective blogs.
From Wikipedia, the free encyclopedia
Tent caterpillars

Tent caterpillars are moderately sized species in the genus (Malacosoma) in the moth family Lasiocampidae. Species occur in North America, Mexico, and Eurasia. Twenty-six species have been described, six of which occur in North America. Some species are considered to have subspecies as well. Although most people consider tent caterpillars only as pests due to their habit of defoliating trees, they are among the most social of all caterpillars and exhibit many noteworthy behaviors.
Tent caterpillars are readily recognized because they are social, colorful, diurnal and build conspicuous silk tents in the branches of host trees. Some species, such as the eastern tent caterpillar, Malacosoma americanum, build a single large tent which is typically occupied through the whole of the larval stage while others build a series of small tents that are sequentially abandoned. The forest tent caterpillar, Malacosoma disstrium, is exceptional in that the larvae build no tent at all, aggregating instead on silken mats that they spin on the leaves or bark of trees. Tents facilitate aggregation and serve as focal sites of thermal regulatory behavior. They also serve as communication centers where caterpillars are alerted to the discovery of new food finds.
Pyrrharctia Isabella
[woolly bears]
The banded woolly bear larva emerges from the egg in the fall and overwinters in its caterpillar form. It survives winter freezes by producing a cryoprotectant in its tissues. Once the weather warms, the larva devours all the grass and weeds it can, pupates, and becomes an adult, which then lives through the summer. It is the larvae of this species which are the subject of common folklore, which has it that the forthcoming severity of a winter can be predicted by the amount of black on the caterpillar; this is the most familiar woolly bear in North America. But in fact, larvae produced in the same clutch of eggs can vary from mostly red to mostly black, even when reared under the same conditions, and this variability invalidates any actual temperature-related trends that may otherwise be evident. In fact, the orange band will grow towards the ends of the body, with the black bands decreasing in size, as the larva matures.


  1. Hullo you,
    Online at the same time, Huh. Was just going back to my stuff after goofing off to post when I saw you on my dashboard and as usual, can't resist....

    Ref reading the stripes;

    guess its important to stop and work out which way the bloomin thing is pointin' otherwise you could be way out!!!


    ps. just had to put silly in for my word verification. Are you trying to play with my mind here??

  2. You now have me racking my brains, trying to remember what UK tent caterpillars look like. i can only think of caterpillars (tent ones? Cannot remember) from my childhood, which had a bright blue stripe along them . . .

    I am wondering about the woolly bears, and the weather, and thinking if you had one of those warm/cold, warm/cold winters, would they then be uniformly banded?!

  3. BB; I found lots of info on the web about woolly bears. It seems that those who study such things have determined that the striping can vary amoungst "bears" from the same hatching of eggs. Probably regional differences in coloring as well. The weather prediction re the bands of color is [of course] a bit of folk lore, but don't we cherish such things.
    Al; if you think the stripes on the caterpillar itself are confusing, can you imagine Mr. Teale and his experiments, shaking up several and remembering which ones were headed in which direction?
    As I say, we never have to be bored, maybe just a bit "silly."