Subject: changing larvae food

From: Gene Bilney <[email-masked]>
Date: Tue, 17 Sep 1996 18:41:55 -0500

Has anyone every experimented with changing a larva's food for 
another? Say you found a Cecropia caterpillar on a silver maple
tree. You take it home and you want to feed it apple leaves in-
stead. Will the larva start eating the apple and survive or will
it not eat and die? Thanks
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From: Michael <[email-masked]>
Date: Wed, 18 Sep 1996 09:21:19 -0700

Gene Bilney wrote:
> =============================================================Howdy, I raise Luna and Imperial.  I have started my Luna on Hickory, and 
switched to Sweetgum (they seem to grow faster on it & like it more).  
And they all did fine.  I have heard from Pete, a cecropia breeder, who 
says that you cannot switch Cecropias.  I'll try them next year.  I have 
also found several caterpillars "walking" thru my yard that I place on 
whatever I think they'll eat (based on research).  They almost always 
continue their eating ways.  And, I can't imagine that, by chance, I put 
them back on the exact same host they came from.  Good Luck, Mike

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From: [email-masked] (Pete Honl)
Date: Wed, 18 Sep 1996 11:14:44 GMT

I have been successful at changing the host plant of  cecropia after
they were a few days old.  I couldn’t get older larva to change.

Apparently this isn’t a strict rule.  While raising polyphemus on
birch, I had to leave town for a few days.  I asked my wife to feed
the larva while I was gone.  I forgot to mention they needed birch.
When I returned, they were happily eating basswood leaves!

Pete Honl

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From: [email-masked] (Charles Sartwell)
Date: Wed, 18 Sep 1996 02:12:07 -0500

A beast with a broad host range like Cercropia should be able to survive
the change from one food species to another. Most caterpillars prefer new
foliage to old; select the newest apple leaves.

In article <[email-masked]>,

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From: [email-masked] (Charles Sartwell)
Date: Sat, 21 Sep 1996 03:16:53 -0500

Another sometimes exception is western blackheaded budworm, Acleris
gloverana, pest of hemlock, spruce, and true firs of forests in coastal
areas of western North America, particularly Alaska and British Columbia.
When endemic, blackheaded budworm usually is found defoliating single
trees from the bottom of the crown upward and from inside of the crown
outward. However, when epidemic, it sweeps the countryside over thousands
of acres making little distinction between old and new foliage.

For most caterpillars showing preference for new over old foliage, the
preference is most evident in early larval instars. This may be more the
case for caterpillars associated with conifers than those associated with
angiosperms. It might be a factor influencing life histories. Conifers
generally put on new foliage just in the spring and early summer.
Angiosperms may flush new foliage throughout a greater part of the year.

> 
> While you guys are all making a lot of common sense, I have come across a 
> very important exception.  Some species feed on Rhus laurina.  Whether 
> cecropia will do so or not, I don't know, but, so I'm told, R laurina 
> stores all its protective toxins in the newer foliage, necessitating the 
> use of older foliage as food for species using it as a host.  One taxon 
> that uses R laurina is Datana persicua californica, which I found near 
> Santa Susana Pass (at the northwest corner of the San Fernando Valley) in 
> Los Angeles County, several years ago.  I have not seen it since, 
> incidentally.
> -- 
> Pierre Plauzoles   [email-masked]
> Canoga Park, California

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From: [email-masked] (Liz Day)
Date: Sun, 22 Sep 1996 12:45:30 GMT

I have heard that if you want to switch foods, do it right after a
larva sheds its skin.  At this time they haven't eaten in a while
and are ravenous.

Liz Day
[email-masked] 
Indianapolis, Indiana, central USA, 40 N latitude.

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From: [email-masked] (Pierre A Plauzoles)
Date: Fri, 20 Sep 1996 19:58:42 GMT

Reposting article removed by rogue canceller.

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From: [email-masked] (Pierre A Plauzoles)
Date: Thu, 26 Sep 1996 08:40:45 GMT

>larva sheds its skin.  At this time they haven't eaten in a while

Hmmm.  Makes sense to me.  By contrast, I have heard that a/ only certain 
will switch at all, and b/ those that will should be switched only after 
the second molt.  Whether this makes any sense to you or not I don't 
know, but I tried some Hyles lineata from the Mojave Desert (California) 
and some 80-90% switched very (!!) readily to grape, but a few refused 
stubbornly as mules.  Three died and two pupated early, producing dwarf 
adults in A-1 condition.  Some eight or so hesitated and then switched, 
going on to fully normal development without further ado.

Would you have expected that from this species?  Not I!