Earwiggy yikes!

[Frederick W. Schueler]

Everyone,

For some time I've been trying to figure out how to make the Parsnip
Webworm into an effective biocontrol for Parsnips -
https://ngtimes.ca/does-mowing-down-the-golden-parsnips-sustain-them/ -
and I recently wrote:

"In the case of Parsnip, the biocontrol agent, the Parsnip Webworm Moth
(Depressaria radiella), arrived on its own, two centuries after their
host plant had been introduced as a garden vegetable, and had evolved
low levels the toxins that inconvenience the Webworms. In the late 1990s
when (documented by analysis of herbarium specimens) the toxins had been
selected back up to European levels, alarms were raised about the
toxicity of 'Poison Parsnip,' and herbicidal and mowing control of
Parsnip began. Both control methods prevent the Webworm from completing
its life cycle, leaving fields and roadsides golden with Parsnip
flowers. On our land we let the Parsnips mature, and this year enormous
numbers of Webworms have woven their brownish web-bundles over flowers &
immature seeds, actually killing some plants, as well as eating up most
of the reproductive potential on most plants."

While it's clear that mowing or herbiciding Parsnips will prevent the
Webworms from completing their life cycle, I've wondered if there may be
parisitoids which go after the Webworm pupae in the Parsnip stems, and
was going to take some stems into a container and see if any little
Wasps emerge from them.

But today we had to trim some Parsnips that were in the way of walking
around the trailer, and when I opened the little webs on them to see how
big the Webworm caterpillars were, there were no caterpillars, but three
of the little webs contained Earwigs.

Google AI says "Earwigs often use the silk webs and bored hollow stems
created by parsnip webworms as convenient daytime shelter. Once the
webworm larvae finish feeding on the flower clusters and move into the
stalks to pupate, nocturnal earwigs move into these protected cavities
to hide from the sun and dry air."

So this is a "wikipedia moment," and a new complication in trying to
understand the relationship between the 'nips and their Webworms.

fred.
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---------Frederick W. Schueler & Aleta Karstad ------------
Fragile Inheritance Natural History - https://fragileinheritance.ca/
6 St-Lawrence Street Bishops Mills, RR#2 Oxford Station, Ontario K0G 1T0
on the Smiths Falls Limestone Plain 44.87156° N 75.70095° W
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Earwig (english substantive for Forficula auricularia): an omnipresent
reminder that humanity is not acclaimed as the dominant species on the
globe, a conclusion recorded in the Earwig’s neatly folded dorsal
Scriptures and revealed by its inscrutable appearance wherever it is not
wanted. ”The earwig can, at the end of its ‘earthly course’ rise up to
kinship with God and eternal life.” Friedrich Nietzsche, 1881, Daybreak:
Thoughts on the Prejudices of Morality, p 47.

[Frederick W. Schueler]

On 8/8/2026 11:37 AM, Frederick W. Schueler wrote:
> But today we had to trim some Parsnips that were in the way of walking
> around the trailer, and when I opened the little webs on them to see how
> big the Webworm caterpillars were, there were no caterpillars, but three
> of the little webs contained Earwigs.

* this may not have indicated any displacement of the caterpillars,
though, since there are now holes in the stems of some of the Parsnips,
made when the caterpillars go into the hollow stems to pupate - I hadn't
anticipated this since most of the webs looked too small to contain a
fully grown caterpillar.