Subject: Re: safe insecticide?

From: [email-masked] (Pollinator)
Date: 9 May 1996 09:42:13 -0400

In article <[email-masked]>,
[email-masked] (Irene) writes:

>Subject:	safe insecticide?
>From:	[email-masked] (Irene)
>Date:	Wed, 8 May 1996 15:07:13 GMT
>
>Hello, everyone,
>
>I   need to know of insecticides that can be sprayed on plants that won't
>decimate bee populations.  
> I am conducting an herbivory experiment this summer, and my plants are
>bee-pollinated (Atropa belladonna, and Datura, in the Solanaceae- the
>potato family).  
>I expect the insects to be a combination of lepidopteran insects and flea
>beetles, and I don't know what else.  

    If your crop is not blooming, bees will not be present, so you need
not be concerned with bees picking up poison.  (I assume you will keep the
crop free of blooming weeds that might attract bees.)

    If the crop is blooming, the label of the proposed material will tell
you what you need to know.  The label directions are not only informative,
they are the law.

    There are two types of bee directions.  One is for materials that are
only toxic by direct contact, and the other is for materials that are
toxic by direct contact and by residue.

    If the label indicates only toxicity by direct contact, you can 
monitor to see the time that the bees finish foraging the blossoms and
make the application after cessation.

   If the residues are toxic, there are tables in most pesticide manuals
that tell how long the toxicity lasts.  Will bees be foraging again within
that time?  If so, switch to a non-residual material.  Another factor is
the blossom of the particular plant.  If the blossom opens in the morning,
and closes in the afternoon, never to reopen, you could use more residual
materials, because the bees will not contact it.

   The greatest hazard occurs from bees gathering contaminated pollen.  It
is carried externally, and the field bee that carries it may be
unaffected, but it will then be fed to brood and young bees that secrete
brood food, causing dieoff, as long as the contaminated pollen lasts. 
Hives can be killed outright, or lose a whole generation of young, making
them consumers rather than producers.  I have fed tons of corn syrup
trying to help bees recover from pesticide misuse, sometimes sucessfully,
sometimes not, but always expensive.

    I live in an area with a lot of agricultural and mosquito spraying,
and I have always been afraid of liability problems, if I were to collect
and sell pollen, though there is certainly a great demand for it.  I fear
that a lot of pollen is sold untested, that is badly contaminated.  Honey
is processed internally by the bee, so poisons would be lost in the honey
stomach of the dead bees, and honey has always tested remarkably pure.

    Powdered forms of carbamates, organiphosphates, and microencapsulated
forms are most often gathered with pollen, as grains size is often
similar.

    Would that all applicators were as cautious as you.  Thank you.

[email-masked]    Dave and Janice Green,  PO Box 1200,  Hemingway,  SC
29554

Practical Pollination Home Page
http://users.aol.com/pollinator/polpage1.html

Afterthought:  Your caterpillars may be susceptible to Bt, which is not
toxic to bees.  A strain of Bt was used for many years to combat wax worms
in supers of comb.  That is another possible alternative.

[email-masked]                                   Dave Green
Practical Pollination Home Page    
http://users.aol.com/pollinator/polpage1.html  
PO Box 1200, Hemingway, SC    29554