Big Oil, Chemical & Farm Machinery companies provide superb Monarch Butterfly Breeding Habitat

Robert Dana robert.dana at
Wed Aug 14 10:03:31 EDT 2002

John is right on this--the milkweed plants under the corn are not seedlings. These are shoots from root fragments created by tillage. I don't know anything about how glyphosate affects common milkweed (A. syriaca), but if John is right in what he says about this, one could ask whether there will be much milkweed survival after a few years of treating the field. The idea that these "seedlings" will continue to be available from seed blown into the field doesn't hold up. It would take at least 2 growing seasons after germination for a plant to get large enough to support monarch development (even then, a single caterpillar would have to go through several plants to reach maturity). Because A. syriaca is strongly rhizomatous, colonies near the field edge will continue to extend rhizomes out into the field, but these won't get more than a few feet into the field.


p.s., John, the grass is probably giant foxtail, Setaria faberi. We don't see reed canary or orchard grass much in cultivated fields.

Robert Dana, Ph.D.
Natural Heritage and Nongame Research Program
500 Lafayette Rd, Box 25
St. Paul, MN 55155
651 297-2367
Email: robert.dana at

>>> "John Shuey" <jshuey at TNC.ORG> 8/12/02 5:32:24 PM >>>

Now try and keep my story straight here - I've been talking from the first
post about the corn - bean rotation and the impact roundup ready beans have
on weeds.  (and ultimately most cropland in this particular rotation)

So I looked at the photo link and here is what I see:
  1.. Its right on the edge of the field - you can actually see stuff that
looks like dense reed canary or orchard grass one row to the left.
  2.. The milkweed in the foreground is not a seedling - looks like 2 yr old
nursery stock to me (which means that it is probably from a root fragment or
a 3+year old seedling)
  3.. Look at the soil - you can see it right??  This is not in conservation
tillage but rather traditional plowed.  I see no signs of soybean stubble
(or any of last year's crop residue for that matter) indicating that it is
not likely that this came out of recent roundup ready beans or herbicide
resistant corn.  In fact - it looks like a traditional field to me (I'd be
trying to work with this farmer if he were practicing in Indiana to get
better practices on the ground)
So what you see is a very typical distortion from Paul.  He takes one piece
of information, builds on it, and then tries to defend the universe that he
so loves.  Here's what he initially said:

    <According to Iowa State entomologists It turns out most of them breed
on milkweed plants
     <growing WITHIN the canopy of crop monocultures such as corn and
soybeans I got to
    <see this first hand during a visit to the area of
    <Morris, Minnesota on July 28 - Aug. 1
     <As you view the following pictures, bear in mind:

      <a) Monsanto and Dupont provided the crop seeds and herbicides that
help the crop to flourish

Dupont may have have something to do with this field, but when I pointed out
that it was very unlikely that Monsanto did (if it has milkweed growing in
it), Paul jumps on his "better living through chemistry" defense of all
things chemical.

I rest my case.

And again in the name of full disclosure, we also have a great relationship
with Dupont, and actually manage a Karner Blue population on land that they
own near Lake Michigan.


John Shuey
Director of Conservation Science
Indiana Office of The Nature Conservancy

-----Original Message-----
From: Paul Cherubini [mailto:monarch at] 
Sent: Monday, August 12, 2002 8:43 AM
To: jshuey at 
Cc: leps-l at; TILS-leps-talk at 
Subject: Re: Big Oil, Chemical & Farm Machinery companies provide superb
Monarch Butterfly Breeding Habitat

John Shuey wrote:

> So - you're telling me that a plant that often spends 2-4 years as a
> "seedling"  (4 or fewer leaves per plant and usually less than 6cm tall)
> while it builds its root system, must manage to seed in at a density that
> carpets the ground and supports monarch larvae (one mature caterpillar of
> which would need to consume several of these tiny plants).

The ground beneath the canopy of GMO corn and soybean plants, especially
at the perimeter edges of the fields, rather frequently has almost a carpet
of milkweed seedlings. In this picture I put in arrows
pointing to three milkweed seedlings, but there are actually
many more seedlings in this photo that are difficult to see.  So as a
caterpillar munches down one seedling it will just wander off
and find another one in the immediate vicinity.

> Paul- you're just making this stuff up aren't you?  It's obvious that you
> actually have no first hand experience with the plants or agricultural
> systems that you are talking about, and that you are willing to
> wildly based on absolute and total ignorance.  Stick to bullshitting your
> California friends 'cuase us simply prairie folk don't buy into to your
> stories.

John, I am just reporting and expanding a bit on the findings of
Iowa State Professor John Pleasants and his colleagues. THEY are the
brilliant Ag school Ph.D's that know midwestern agroecosystems inside and
out and deserve credit for enlightening us about the importance
of agricultural habitats to monarch butterflies.

As a matter of fact, two years ago I mistakenly argued here that milkweed
was not common in corn and soybean fields because one does not see too
many mature weeds of any kind growing in these fields. The
fields appear weed free as in this picture 

It is only when you go looking inside the canopy of these
crop plants that you see the numerous milkweed seedlings like this one 

Paul Cherubini


   For subscription and related information about LEPS-L visit: 

More information about the Leps-l mailing list