Camping Caterpillars

Yes, I am aware that the gardening year has come early in North America.  And it has discombobulated just about every plant species and human gardener beyond any historical measure.  Now, similarly scrambled, it seems the insects are joining the parade.  Early, Early, Early.

I noticed this weekend that I already had two of these delightful little fuzzy caterpillar nests in a young ornamental cherry tree.  I tend to lump all these creepy, crawling little blights under the term "webworms", but a little research tells me that in my area, in the Spring and in a cherry tree, these are likely Eastern Tent Caterpillars (Malacosoma americanum).  The real webworms, (Hyphantria cunea) occurs in the fall and are less discerning upon which trees they inflict.  Of course, my invasion could be gypsy moths or Forest Tent Caterpillars, but to discern the differences, I'd have to let these barely visible white caterpillars mature a little bit, and I'm not about to do that.  Odds being what they are, for the sake of simplicity, let us just call these Eastern Tent Caterpillars. 

As an interested amateur biologist, I was fascinated to read how their tents are oriented to face the southeast, taking advantage of the strongest rays of the early Spring sun to warm them up in the cooler air.  And as a veterinarian, I was previously unaware that they have been linked to "Mare Reproductive Loss Syndrome."  It seems that when pregnant mares are fed the caterpillars, they abort.  No one is sure of the exact pathogenesis, but the causal link is well established.  I'm astonished that the link was even made; I mean, who sits around watching their pregnant mares eat Eastern Tent Caterpillar nests?

Regarding control of these little beasties, I find myself doubtful about the common recommendation to simply tear a hole in the silk to let the birds get at the caterpillars.  What would stop the caterpillars from reforming their "tent", since they reportedly add to its size every day?  I'm therefore sad and embarrassed to admit that I resorted to dousing these babies with a Sevin drench.

In my defense before the court of the WEE (Wild-Eyed Environmentalists), this tree is an ornamental and doesn't produce edible cherries so both the birds and myself are safe.  But them caterpillars are toast!