Date: Thu, 5 Aug 1999 07:08:21 +0000 From: "Susan Farrington" <sfarrington@ridgway.mobot.org> To: cp@opus.hpl.hp.com Message-Id: <aabcdefg2817$foo@default> Subject: Thrips and chemical controls
To throw in my two cents... Sylvia is certainly right that we too
often choose to rely on chemicals, rather than looking at other
solutions. Chemicals are necessary sometimes, but I think we can all
agree that they have some nasty side effects, and when we CAN avoid
them, wouldn't it be better? Perhaps for an individual grower with
just a few plants, a pesticide is the easiest approach. But on large
scales, pesticide use can certainly be frightening, and much of the
scientific study today is aimed at reducing such use in agriculture.
As to biological controls, I'm not familiar with a wasp that attacks
thrips (although wasps DO come in very small sizes, Tom, and there
might be one small enough to parasitize thrips.) I AM
familiar with several mites and a bug that all will eat thrips:
Hypoasis miles, Ambylsrius degenerans, A. cucumeris and the Insidious
flower bug (great name!): Orius insidiosus. All are available from
the Green Spot, a company in New Hamshire: (603) 942-8925, and from
other companies as well, I'm sure. These predators would not be cost
effective for a person with a few plants, but larger growers should
certainly consider it!
Susan Farrington
> At the greenhouse at Humboldt State they use no pesticides. There are
> thrips on the sarrs and there are also wasps that are thrip parasites.
> They lay their eggs in a thrip. It isn't always pretty but it works in a
> fine natural balance. We are addicted to quick fixes and the nonsense of
> the fifties "better living through chemistry". There is ever increasing
> evidence that pesticides are very harmful to all living things. They are
> linked to lymphomas and much more. I have long been puzzled that this
> list is so protective of cp's in the wild but often seems out of touch
> with a larger picture.
> Sylvia De Rooy
>
Susan Farrington
Missouri Botanical Garden
P.O. Box 299
St. Louis MO 63166-0299
susan.farrington@mobot.org
(314)577-9402
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