Re: Iris Borers
- To: Multiple recipients of list <i*@rt66.com>
- Subject: Re: Iris Borers
- From: "* G* C* <j*@erols.com>
- Date: Sat, 31 Jan 1998 10:54:49 -0700 (MST)
ECPep@aol.com wrote:
>
> Is the borer protected from Cygon use after hatched and inside, that is not on
> any surface, of the plant. Can the borer be dispatched at any age or is it
> safe from Cygon after reaching the rhizome (where I presume it does most of
> the damage)
>
>
Claire -- Speaking from experience, I am sorry to tell you that the
borer apparently is unaffected by Cygon once it is inside the plant. I
find that Cygon spraying in the early spring is very effective, but
there are always a few borers that survive (i.e., fewer than a dozen
among hundreds of clumps). This is despite the fact that I soak the
plants, spraying from all angles, in an effort to get complete
coverage. This apparently means either that (1) they were already
inside the plant when I sprayed, or, (2) in some way, the soaking missed
them, or (3) they hatched from eggs missed by the spraying. I would hate
to think that there is more than one hatching cycle and that the moth
can deposit eggs after the spring spraying which then hatch that same
growing season. My most costly losses have been when seedlings have been
discovered with serious borer damage in July or August, after showing no
prior evidence of borer activity. At any rate, these few borers have
fattened up on irises that have been soaked with the systemic. Anyone
want to offer more testimony for beneficial nematodes?
Griff Crump, along the tidal Potomac near Mount Vernon, VA
jgcrump@erols.com
