Over the years, my biggest grape pest has been the grape flea
beetle. They wouldn't be so bad if they only ate holes in the grown
leaves but they also arrive early. The early ones wait for the leaf
buds to swell and they eat a hole and hollow out the center. Some
years, I take a thimble sized amount of pesticide (such as Sevin)
and use an artist brush to paint it on the biggest of the early buds.
That doesn't answer your question. I'm just talking.
Japanese beetles.... not too many years ago, I had never seen one
around here. I was kind of hoping it was too cold for them to live
here. Then one year, I found one. The next year, there were a few,
then several, then a bunch, then last year, there were enough to
actually do some real damage to the grape vines. Assuming the trend
continues, I'll probably spray them with something this summer.
I've never had the caterpillars. Do you have them every year or just
last year? If they return, it would be interesting to find out
exactly what they are and what they turn into when they grow up.
How organic do you need to be? Are you willing to use a natural
insecticide? Rotenone would probably be effective on both pests.
Maybe an oil spray? There are horticultural oils mad from vegetable
oil. If you want to use no pesticides of any kind, that probably
only leaves a physical barrier. Have you ever used Remay fabric? You
might try draping some of that over the top and sides of your grape
vine during the Japanese beetle season. A few might get in under it
but I bet most would just land on the fabric and wish they were inside.
Let us know what you try and how it turns out.

Steve



wrote:

gee, i'm sorta in the same area as you guise...usda zone 4 in new
hamster...and i was wondering...do either of you ever have troubles with
japanese beetles defoliating your grape leaves as well as this particularly
HUGE catepillar devouring what's left?? man!!! i had SO MANY catepillars on
my concord grape i had (ahem) catepillar manure...enough to form quite a
manure heap and make me wonder if there's any benefit to catepillar manure?

at any rate, to make a short story long, can you guys suggest any ORGANIC
method to protecting the poor little grapies from these horrid buggers??

thanks, in advance.