Ask A Scientist© Botany Archive

  
name        Neil
status      other
age         30s

Question -     I have a "Pin Oak" tree. There are these (I don't know what you would
call them)slug, not slug. I just planted this tree 3years ago. It
stands 7 feet tall and is no wider than 3 feet. Any way, these so-call-
ed slug things, start out very small, approx. 1mm wide by 2-3mm long.
They grow in size, by eating or sucking the juice from the tree. They
seem to eat or suck the new formed buds from the tree. I find them
underneith on the branchs, but more so toward the ends. These pests
are cleverly hidden. You wouldn't know their an insect until you look
very close such as I did.
Ants are attracted by them. The ants can't harm them because they
have some type of armor on the out side. The ants are how I found these
pests. They grow in size and when you poke them, their pusy like.
I never see them move. I only see new little ones each day.
There killing my tree I planted for my son!!! Please, what are they?

sounds like caterpillars.

http://www.dnr.state.wi.us/org/land/forestry/fh/insects/gmguide.htm
http://www.forestworld.com/forestry/outreach/pestalerts/oakleaf/oakleaf.html

contact your local agricultural extension office for help.

Sincerely,
Anthony R. Brach, Ph.D.
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