Sounds like caterpillar poop to me. It would be good to identify the type
of caterpillar you are dealing with. You could call your local extension
agent, or take a specimen to a garden center (not a big box store)--they
often have someone on staff who will know, or will look it up for you. In
general, caterpillars can be controlled by spraying with Bt. This is a type
of bacteria that is only toxic to caterpillars. They need to eat a from a
treated leaf; they stop feeding and die in a few days. On a large tree it's
difficult to spray all the surfaces, but you can still make a big dent in
the population.

I feel Bt is a good product for certain situations; however, it is important
to realize that is it indiscriminate in which caterpillars it kills--monarch
and swallowtail butterfly larvae are just as susceptible as webworms. So
when I use it I am careful to do it when it's not windy, to minimize
drifting, and to aim carefully. I treat a locust tree that overhangs my
deck for webworms, but choose not to treat trees around the perimeter of the
property where I might be putting butterflies at risk.

Cheers,
Sue

Zone 6, Southcentral PA


"PRHD" wrote in message
...
I have a dumb question...we have an ash tree that hangs over our deck.
Every
year at this time, the deck is covered in coffee ground looking stuff
falling
from the tree. At the same time, there are at least a billion little green
caterpillars/worms munching away at the leaves. I think the coffee ground
stuff
is caterpillar poop...hubby thinks it's from the tree itself, and that's
why
they call it an ash tree. (either that or he just told me that to keep me
from
being disgusted about caterpillar poop)
so, can anyone tell me, do ash trees drop some sort of "ash" ? or am I
right in
my caterpillar theory?

another question....how do you rid the tree of the things? it's a mature
tree,
was here when we bought the house, so all I know is it's an ash and it's
big.
I figured the only way to get rid of them is to spray with something...but
how
do you spray a tree that big? or is it a lost cause and we just have to
deal
with the squirmers every year?

pam