CAES Newswire

 College of Agricultural & Environmental Sciences UGA Cooperative Extension
Menu
Published on 10/25/23

Unveiling the fearsome hickory horned devil

By Emily Cabrera
Regal moth looks into the mirror to see a hickory horned devil
The caterpillar relies on its appearance to deter attackers and, when disturbed, aggressively twists and writhes on the ground to defend itself. In its final, less terrifying form, the regal moth displays autumnal-colored wings in shades of deep orange with gray stripes and yellow spots. (Art by Jay B. Bauer)

With a name that conjures the spookiest Halloween imagery, the hickory horned devil (Citheronia regalis) caterpillar is a marvel of nature's creativity, boasting a fearsome-looking appearance that is both off-putting and intriguing.

With its mint-green body adorned in tubercles with jet-black tips, this nightmarish caterpillar appears dangerous, but don't let appearances deceive you. This creature is no monster, it's a marvel of adaptation.

This time of year, unsuspecting passersby may have the rare chance to spot this spectacular caterpillar as it drops from trees. Plump from months of feeding on the leaves of hickory, black walnut, sweetgum, pecan and persimmon trees, this 6-inch behemoth has all the nutrients it needs to burrow into the ground for the cooler months ahead. Entombed in an earthen cell, it will soon undergo the process of metamorphosis.

Will Hudson, a professor in the Department of Entomology at the University of Georgia’s College of Agricultural and Environmental Sciences, ensures us this gruesome-looking caterpillar is more enchanting than it is menacing.

“Those fearsome-looking spines are, in fact, soft to the touch and pose no danger to humans — they don’t sting or bite,” he said. “Its threatening appearance is simply an evolutionary defense mechanism to ward off predators.”

The caterpillar relies on its appearance to deter attackers and, when disturbed, aggressively twists and writhes on the ground to defend itself.

“They’re also not considered to be a pest,” said Hudson. “While they can certainly eat a lot during the summer months, they’re not gregarious, so you don’t have infestations that could defoliate a tree.”

In early spring, the native insect emerges from its underground tomb, having traded its spooky spines for large, graceful wings adorned with striking patterns as the regal or royal walnut moth (Citheronia regalis).

In its final, less terrifying form, the regal moth displays autumnal-colored wings in shades of deep orange with gray stripes and yellow spots. With a wingspan of up to 6 inches, it’s a marvel to behold.

“It’s a very special caterpillar,” said Hudson. “We shouldn’t try to assess how valuable an insect is as it pertains to us. Just enjoy it if you get a chance to see one.”

So the next time you go on a walk, keep watch for this Halloween-worthy creature, and remember, there's often more to creepy crawlies than meets the eye. Contact your local UGA Cooperative Extension agent for help identifying things that go bump in the night (or, better, cool insects).

Emily Cabrera is a writer for the College of Agricultural and Environmental Sciences at the University of Georgia.

Authors:
Emily Cabrera
Experts/Sources:
Will Hudson
University and state leaders cut the ribbon during the Science and Ag Hill dedication ceremony. (Chamberlain Smith/UGA) CAES News
UGA dedicates first phase of Science and Ag Hill modernization 11/01/24
The University of Georgia held a dedication ceremony on Oct. 30 to celebrate the completion of the first phase of renovations to modernize research and instruction facilities and infrastructure on UGA’s Science and Ag Hill. This area of campus, located just south of Sanford Stadium, includes buildings dedicated to a variety of scientific disciplines such as biology, physics, geology and agricultural sciences.
CAES doctoral students Sofia Varriano and Leniha Lagarde follow farmer Clay Brady to the pasture where many of his chickens are kept. CAES News
UGA researchers study how free-range chickens influence farm sustainability 10/31/24 Maria M. Lameiras
Researchers in the University of Georgia College of Agricultural and Environmental Sciences are studying how pastured and free-range chickens impact ecosystems on integrated crop-livestock farms. Supported by a $749,000 grant from the U.S. Department of Agriculture’s National Institute of Food and Agriculture, entomology doctoral student Sofia Varriano and her thesis advisor, agroecologist and systems biology Professor Bill Snyder, are testing the promise of integrated crop-livestock agriculture to increase the sustainability of smaller farms.
The study represents the most detailed and comprehensive picture to date of the health of the monarch fall migration in Eastern North America. (Photo courtesy of Pat Davis) CAES News
The monarch butterfly may not be endangered, but its migration is 10/22/24 Leigh Hataway
With vigorous debate surrounding the health of the monarch butterfly, new research from the University of Georgia may have answered the biggest question plaguing butterfly researchers. Why are the wintering populations declining while breeding populations are stable? Published by the Proceedings of the National Academy of Sciences, the study suggests that monarchs are dying off during their fall migration south to Mexico.
Jennifer Berry, Apicultural Research Professional and Lab Manager for the UGA Honey Bee Program, recently achieved her Ph.D. and Triple Dawg status. She has been working with the Honey Bee Program at UGA for over 20 years. (Photo by UGA College of Agriculture and Environmental Sciences.) CAES News
Queen bee: Berry turns a sweet hobby into research and impact 08/20/24 Brandon Ward
Jennifer Berry has always been interested in insects. As a child, she would spend time in the woods behind her house, fascinated by the multi-legged life that lived among the trees. In summers, Berry visited her grandparents’ Missouri farm, where her grandfather would take her to a buzzing tree to collect bits of honeycomb. After safely smoking out some of the bees, he would hold Berry up to see the hive and take a couple of small combs for them to enjoy. “I always wanted more,” she said.
LiceCheck CAES News
A back-to-school guide to the nitty-gritty on head lice 08/12/24 Allison Johnson
As students return to school, head lice often become a common concern for administrators and parents. Understanding how to prevent and manage head lice infestations is crucial for maintaining healthy environments in schools and at home. Allison Johnson, the Pesticide Safety Education Program coordinator for the University of Georgia, provides essential information and advice to help mitigate the spread of this pesky pest.
European paper wasp on nest. CAES News
Ouch! What just bit me? 08/08/24 Elmer Gray
As autumn approaches and the stifling heat of summer begins to cool down, spending more time outdoors may be on your radar. But, as Georgia is home to many stinging and biting insects, fall fun can turn into a minefield of discomfort. Elmer Gray, a research entomologist with the University of Georgia College of Agricultural and Environmental Sciences and specialist for UGA Cooperative Extension, shares information on some of the season's most common culprits, urging residents to stay vigilant and take preventive measures.