rec.gardens.ecosystems homepage -> archive: MOD$990502.13298@rec.gardens.ecosystems



Subject: Re: Captan fungicide question
From: "Don & Jeanne Chapman" <chappy@gowebway.com>
Organization: VCNet - Internet Access of Ventura Country (vcnet.com)
Date: Sun, 02 May 99 11:23:06
Message-ID: <MOD$990502.13298@rec.gardens.ecosystems>
References: <MOD$990430.14026@rec.gardens.ecosystems> <MOD$990501.4344@rec.gardens.ecosystems> <MOD$990501.8592@rec.gardens.ecosystems>



Rev Chuck wrote in article
<MOD$990501.8592@rec.gardens.ecosystems>...
>
> Orangerose wrote:
> >
> > Of particular concern to me (with Captan) is the data on the residual effect
> > within the plant. Also, since it is a fungicide, I would assume that Captan is
> > quite toxic to beneficial fungi.
Some fungicides are more harmful to beneficial mycorrhizal fungi than
others. In general, the contact-type fungicides and seed coatings seem to
do little harm. However, soil drench fungicides and systemics can be very
damaging.

Just as with broad-spectrum insecticides (which kill off everything, good
and bad insects alike), the idea of destroying all fungi (helpful as well
as harmful) is coming to be seen as bad strategy for growers. Many types
of fungus are essential to plant health and performance, and most others
are indirectly helpful (decomposing organic matter into forms plants can
use), and only a very few are harmful. And, most important, if there are
good populations of beneficial types, they will help keep the "bad guy"
fungi away from plants (again, much like beneficial insects help growers).

Instead of looking for "something to pour on the problem", gardeners would
do much better to encourage the beneficials down there. The results would
be much better.

>
> Looked at the abstracts. Apparently low toxicity, but is an unnaturally
> "perfect" apple worth the unknown risks? Residual effects would be of
> concern to composters, wine and hard cider makers. I wonder if soil
> residues might decimate symbiotes, lessening nutrient availability.
>
> As it now stands, I found a nearby Mom and Pop feed store that carries
> untreated seeds. Helps to get away from the corporate retailers.
>
> > Where's our bio-organics expert? (Mr. Chapman?)
>
> Any relation to American folk hero "Johnny Appleseed" Chapman?

Possibly. Jonathan Chapman was a nurseryman who actually dealt more with
seedling trees than seeds, but I obviously do feel some kinship in spirit.

Don Chapman
Chappy's Power Organics
3200 Corte Malpaso, #107
Camarillo CA 93012
Info & Orders <http://www.bio-organics.com>