Explore Plants

Share

Ask Mr. Smarty Plants

Ask Mr. Smarty Plants is a free service provided by the staff and volunteers at the Lady Bird Johnson Wildflower Center.

Search Smarty Plants
    
 

Can't find the answer in our existing FAQs, submit a question to Mr. Smarty Plants.
Need help with plant identification, visit the plant identification page.

rate this answer
Not Yet Rated

Saturday - September 29, 2007

From: Houston, TX
Region: Southwest
Topic: Wildlife Gardens
Title: Caterpillars on Carolina buckthorn (Frangula caroliniana)
Answered by: Nan Hampton

QUESTION:

I have a Carolina buckthorn and last year there were interesting looking caterpillars munching on the leaves. They were camouflaged to look a bit like bird droppings. The plant database makes no mention of Carolina buckthorn as being a larval host. What species of caterpillars might they be?

ANSWER:

Mr. Smarty Plants found Carolina buckthorn (Frangula caroliniana—synonym=Rhamnus caroliniana) listed as a host plant for caterpillars of gray hairstreak (Strymon melinus), spring azure (Celastrina ladon), and painted lady (Vanessa cardui) in Caterpillar Food Plants for Central Texas compiled by Mike Quinn, Invertebrate Biologist, at Texas Parks and Wildlife Department. Unfortunately, none of these caterpillars look very much like bird droppings. Another source identified caterpillars of Henry's elfin (Callophrys henrici) feeding on Carolina buckthorn. Again, it would be a stretch of the imagination to confuse these larvae with bird droppings.

At this point, Mr. SP decided it was time to contact the butterfly/caterpillar expert, Mike Quinn, for further insight. He offered a few more caterpillars of Texas butterflies that feed on plants of the genus Rhamnus, but not specifically on Rhamnus caroliniana (=Frangula caroliniana):

Spilosoma vestalis (Family Arctiidae)

Itame guenearia (Family Geometridae)

Pero macdunnoughi (Family Geometridae)

Triphosa californiata (Family Geometridae)

Cnidocampa flavescens (Family Limacodidae)

Celastrina argiolus (Family Lycaenidae)

And, as Mike says: "Arctiids are hairy, geometrids are inchworms, limacodids are generally
bizarre, and lycaenids are slug-like. None in my opinion are particularly bird-dropping like."

Mike pointed out that the classic bird-dropping larvae are those of the swallowtails. The only swallowtail reported to host on plants of the genus Rhamnus is the pale swallowtail (Papilio eurymedon) and it doesn't occur in Texas.

Nick Grishin, a professor at Southwestern Medical Center, suggested your larvae could possibly be sawfly larvae and not butterflies or moths at all. Sawflies are a group of insects in the order Hymenoptera, the same order that contains bees and wasps. Sawfly larvae do resemble butterfly and moth caterpillars and although there is no specific reference to any of them feeding on Carolina buckthorn or other species in the genus Rhamnus, they do feed on shrubs and trees and a few might be said to look a little like bird droppings.

So, these are some possibilities. If none of these looks like "your" larvae, perhaps you will see them again next year and can photograph them to send to Mr. SP for possible identification.

 

More Wildlife Gardens Questions

Hybrid of Campsis radicans to attract hummingbirds
February 06, 2008 - Hello :) I am not new to gardening...just new with new varieties of plants/flowers. I tried to do my "homework" first before contacting you...so I do appreciate your time. Anyhoo, I'm developin...
view the full question and answer

Schedule for pollen and nectar for bees in Austin
May 27, 2010 - For beekeeping in western Travis County (Cuernavaca at Bee Caves) I need to know what nectar and pollen is flowing when. I have asked my local beekeeping club, but they are in Blackland Prairie and d...
view the full question and answer

Color year round, welcome to Austin Texas.
December 04, 2011 - I am new to Austin and want to plant colorful flowers for fall and winter that get a "wow" reaction. I have not seen much at the local nurseries. Any and all suggestions are greatly appreciated!
view the full question and answer

Native Bird Feeding in Belton, TX
July 04, 2011 - We recently bought a bird feeder and a huge bucket of non-native bird seed (I'm not sure if the whole seed mix is non-native, but I believe most of the mix is). The birds go through the whole bird fe...
view the full question and answer

Bird attracting plants in Northeast U.S.
March 22, 2004 - What plants will attract birds in zone 6 (Northeast) in the spring and early summer?
view the full question and answer

Smarty Plants's Facebook profile Support the Wildflower Center by Donating Online or Becoming a Member today.

Mr. Smarty Plants wants you to be his Facebook friend. Click the Facebook icon to add yourself to Mr. Smarty Plants list of friends.