"Jean B." expounded:

Hmmm. I haven't seen anything on them, so tomorrow I will look
closer. I did notice that my nishiki willow looked nice one day
and half naked the next day, and closer inspection revealed
caterpillars. If there are, indeed, caterpillars, can one spray
or something?

We have a new pest, the winter moth, and the caterpillars are
voracious eaters, like the canker worm. Remember last November all
those little white moths in your headlights? That's the buggers.

I have problems with the canker worms, so I spray every spring,
starting with leafout, with a BT spray on my cherries and flowering
almond. You have to start when they're young, they measure them by
instars or somesuch, when they're more than a half-inch long I think
they're too big for the BT to overcome them. Unfortunately at this
point I think only sevin will kill them, but you know all else that
will kill! If this is the first year of your infestation then the
trees and shrubs will releaf and recover. Next spring be sure to hit
them early and hard with the BT spray. Hose-end sprayers are cheap
and they spray 30' or so, so it isn't a problem to use them on
ornamental trees. Unfortunately the same can't be said of the oaks,
they've taken a hard hit, too, but they're too tall for me to spray
(

--
Ann, Gardening in zone 6a
Just south of Boston, MA
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