What Do Hickory Horned Devils Eat? A Friendly Guide to Their Diet

When you come across the caterpillar known as the hickory horned devil, you might find its appearance quite intimidating. However, despite its ferocious looks, these creatures are entirely harmless. As the largest caterpillar in North Carolina, the hickory horned devil can measure almost 5 inches long when fully grown.

These vibrant caterpillars munch on a variety of trees, with their preferred menu consisting of hickory, persimmon, sassafras, sourwood, sumac, sweetgum, sycamore, walnut, and other shade trees source. As they grow, their primary goal is to consume leaves to fuel their transformation into the regal moth, also known as the royal walnut moth.

As fascinating as they are, hickory horned devils aren’t considered harmful to most landscapes. Most trees they feed on can easily recover from their leaf consumption. As a result, your appreciation for these fascinating creatures can be both a visual adventure and a learning experience, all without worrying about their impact on your surroundings.

Hickory Horned Devils: An Overview

The hickory horned devil is a type of caterpillar that belongs to the Citheronia regalis species. Despite its intimidating appearance, this devil caterpillar is actually harmless.

These hickory horned devils are native to North America and have a noticeable presence in the eastern and southern regions. During their larval stage, they primarily feed on leaves from trees such as:

  • Hickory
  • Walnut
  • Pecan
  • Persimmon
  • Sweetgum

The hickory horned devil caterpillars go through a number of molts as they grow. When mature, they can reach up to 5.5 inches (14 cm) in length. Their unique appearance includes:

  • Green, black, and cream markings on their bodies
  • Yellow to orange curved horns behind the head
  • Light blue markings in some instances

These caterpillars are not dangerous or harmful to humans. In fact, their horns and spines are quite flexible and not poisonous.

So, if you come across a hickory horned devil in your backyard, there’s no need to be alarmed. Just admire its unique appearance and remember that this fascinating creature is just going through its natural life cycle before transforming into a regal moth.

Physical Characteristics

Coloration

The Hickory Horned Devil, also known as the Regal Moth caterpillar, displays a range of vivid colors throughout its life stages. As a larva, it is predominantly green, with yellow, black, brown, and orange accents. Some rare specimens may even exhibit turquoise or grayish hues.

Size and Appearance

The size of hickory horned devils varies depending on their life stage. As caterpillars, they can grow up to 5.5 inches long, making them one of the largest caterpillars in North America. In their adult moth stage, their wingspan can reach an impressive 6 inches.

Caterpillars of the hickory horned devil are known for:

  • Large, curved horns on their heads
  • Spiky, harmless spines along their bodies
  • Distinctive bands of various colors

Notable Traits

Despite their intimidating appearance, hickory horned devils are harmless to humans. They are more known for their fascinating appearance, rather than being a threat.

Some traits of the hickory horned devil include:

  • Non-aggressive behavior
  • No bite or sting
  • Rare sightings due to their nocturnal nature

Egg Stage

The hickory horned devil’s life cycle starts with the egg stage. Female moths lay clusters of eggs on the underside of host plant leaves, such as hickories and walnuts. These eggs are typically cream or light brown in color and hatch into tiny caterpillars within a few weeks. As they grow, the larvae will molt several times, gradually developing the unique coloration and traits that define this remarkable insect.

Habits and Lifestyle

Distribution

The hickory horned devil is a North American moth, commonly found in the eastern half of the United States. Its geographical range spans from central Florida up to Massachusetts, and westward to Missouri, eastern Texas, and parts of New York and New Jersey.

Feeding Habits

You might be surprised to learn that hickory horned devils primarily feed on leaves. Their diet includes a variety of tree leaves from species such as:

  • Hickory
  • Persimmon
  • Sassafras
  • Sourwood
  • Sumac
  • Sweetgum
  • Sycamore
  • Walnut

These caterpillars are known for their voracious appetite, consuming a significant amount of foliage during their growth period.

Life Cycle

The life cycle of the hickory horned devil is quite fascinating. It starts when a regal moth lays hundreds of eggs. After hatching, the tiny caterpillar begins its journey towards maturity. Over a few weeks, it goes through a series of molts, growing in size until it becomes the large and fearsome creature you might encounter.

As the caterpillar prepares to pupate, it descends from its host tree and burrows into the ground. Here, it forms a pupa and overwinters until the following spring, when it emerges as a fully developed regal moth. Once they emerge and mate, the cycle continues with the next generation of hickory horned devils.

Diet

Primary Food Source

Hickory horned devils are known for their voracious appetite, primarily feeding on leaves. The caterpillars have a strong preference for hickory-type trees such as Carya and Juglans species. These trees provide the main source of nutrition for this caterpillar as it grows.

Examples of favored trees include hickory, walnut, and pecan. Hickory horned devils will feast on leaves from these trees, ensuring they have plenty of energy to continue their development.

Additional Host Plants

In addition to hickory and walnut trees, hickory horned devils may also feed on leaves from a variety of other host plants. Some examples are:

Other potential host plants include buttonbush, filbert, and even leaves from some Juglans cinerea trees. Although these plants might not be hickory horned devils’ first choice, they can still provide sustenance when their preferred trees are not available.

Here’s a comparison table of some common host plants:

Host Plant Scientific Name Type of Tree
Hickory Carya Nut
Walnut Juglans Nut
Pecan Juglans cinerea Nut
Sweetgum Liquidambar styraciflua Hardwood
Persimmon Diospyros virginiana Fruit
Ash Fraxinus Hardwood
Sycamore Platanus Hardwood

As you can see, the diet of the hickory horned devil is quite diverse and adaptable. The caterpillar’s ability to feed on a range of host plants ensures that it can find the nutrients it needs to grow and complete its life cycle successfully.

Habitat

Hickory horned devils are usually found in deciduous forests, where they can thrive and find food sources. In these forests, you’ll come across various tree species such as hickory, walnut, and sweetgum – which are some of the primary food sources for these fascinating creatures.

These caterpillars prefer habitats with a mix of tree species like hickory, persimmon, sassafras, sourwood, sumac, sweetgum, sycamore, and walnut, as mentioned on this NC State University page. By living in such environments, hickory horned devils can find plenty of food to sustain their growth.

To give you a clearer picture, here’s a list of some common tree species found in deciduous forests where hickory horned devils thrive:

  • Hickory
  • Walnut
  • Sweetgum
  • Persimmon
  • Sassafras
  • Sourwood
  • Sumac
  • Sycamore

These habitats provide a safe and nurturing space for the hickory horned devil caterpillars to grow and eventually transform into regal moths. Remember, as you explore deciduous forests, don’t be afraid of these fascinating creatures, as they pose no threat despite their intimidating appearance.

Predators and Threats

The hickory horned devil, scientifically known as Citheronia regalis, is a fascinating caterpillar with striking features, but what sort of predators and threats does it face in its natural habitat?

While you might think its large size and intimidating appearance would deter potential predators, there are some creatures that still pose a threat. For example, birds are known to prey on caterpillars, and the hickory horned devil is no exception. Some bird species, such as woodpeckers and blue jays, may be more likely to target these insects for a meal.

In addition to birds, snakes can also be predators for the hickory horned devil. Although they might not seem like the most obvious threat, snakes that are able to climb trees in search of prey may find these large caterpillars an appealing target.

When discussing predators, it’s important to also consider parasitic wasps. These insects lay their eggs inside caterpillars, and when the eggs hatch, the wasp larvae feed on the host. In some cases, hickory horned devils may fall victim to these parasitic insects, making them another potential threat.

It’s worth noting the following key points about the predators and threats faced by hickory horned devils:

  • Birds, snakes, and parasitic wasps are the main predators.
  • Despite their size and appearance, hickory horned devils are still a target for certain species.
  • Climbing snakes may pose a particular risk due to their ability to reach the caterpillars’ natural habitat.

While the hickory horned devil does face some challenges in the form of predators and other threats, its unique appearance and size can also act as a deterrent for some potential foes. Keep an eye out for these fascinating insects and be sure to give them the respect they deserve.

Moth Stage

Regal Moth

The hickory horned devil goes through a pupation stage in the soil before emerging as an adult moth, commonly known as the regal moth or the royal walnut moth. These moths are quite large and are a part of the Citheronia genus.

Their bodies have a distinct coloration, with rusty-orange hues mixed with yellow bands. You’ll notice that the forewings of the regal moth have grayish and rusty-orange stripes, alongside large yellow spots. In comparison, their hindwings lean more towards the orange side, with even larger yellow markings.

Here are some key features of the regal moth:

  • Part of the Citheronia genus
  • Also known as the royal walnut moth
  • Rusty-orange body with yellow bands
  • Grayish forewings with rusty-orange stripes and yellow spots
  • Orange hindwings with large yellow markings

During the moth stage, the regal moth does not consume any food. As an adult, its primary purpose is reproduction. So, if you were wondering what hickory horned devils eat during the moth stage, the answer is simple – they don’t.

The hickory horned devil transforms from a large, colorful caterpillar to a beautiful moth. Its primary purpose is reproduction, but in this final stage, it doesn’t consume any food. So, enjoy the sight of this fascinating creature knowing that it has no dietary needs during its moth stage!

Interactions with Humans

As a fascinating creature, hickory horned devils might pique human curiosity. Despite their ferocious appearance, these caterpillars are harmless, and their horns and spines are flexible to the touch, not very sharp, and not poisonous.

You might encounter hickory horned devils on certain trees, as their diet consists of leaves from various tree species like hickory, walnut, and sweetgum. According to research conducted by the University of Florida, you don’t need to worry about these creatures damaging trees, as they usually don’t occur in large enough numbers to cause significant defoliation.

While hickory horned devils might appear frightening, educating yourself and others about these creatures can help dispel misconceptions. They play a valuable role in the ecosystem, and their adult form—the regal moth—is an attractive addition to our natural environment.

In summary, your interactions with hickory horned devils can be quite interesting and educational, as long as you approach these creatures with respect and curiosity.

Trivia and Additional Facts

The hickory horned devil is known as the largest caterpillar in North America and belongs to the Citheronia genus. It is part of the Saturniidae family and the Ceratocampinae subfamily. Some of its relatives include the cecropia moth, another giant among moth species.

These fascinating creatures have a life cycle that includes devouring plant leaves. The hickory horned devil commonly feeds on the leaves of walnut, hickory, pecan, persimmon, and sweet gum trees. As they grow, their appearance is marked by the presence of prominent spikey horns. However, despite their intimidating look, they are harmless.

While in their larval stage, these caterpillars will shed their skin several times. To move into the next stage of their lifecycle, hickory horned devils will display a unique behavior. They form themselves into a distinct J-shape and burrow into the ground where they eventually pupate within a cocoon.

In the Lepidoptera order of insects, hickory horned devils and their adult version, the regal moth, were first described by Fabricius in 1793. These fascinating moths utilize pheromones to communicate with potential mates and are generally nocturnal, making them rare to spot during the day.

A quick comparison of the hickory horned devil and the cecropia moth larvae:

Feature Hickory Horned Devil Cecropia Moth
Size Largest caterpillar in North America Second-largest caterpillar
Host Plants Walnut, hickory, pecan, persimmon, and sweet gum Preference for Rhus Tree leaves
Defensive Features Prominent spikey horns Less intimidating appearance
Ground Burrowing Yes, for pupating No, prefers tree cocoon

So, the next time you encounter a hickory horned devil caterpillar, keep in mind its unique features and fascinating life cycle. Remember, despite its scary appearance, it is harmless and plays an important role in the ecosystem by controlling plant growth and serving as prey for other wildlife.

Reader Emails

Over the years, our website, whatsthatbug.com has received hundreds of letters and some interesting images asking us about these insects. Scroll down to have a look at some of them.

Letter 1 – Regal Moth Pupa

 

a couple pictures of regal moth (Citheronia regalis) pupa
Hi,
I knowticed on your site that you guys were “lacking” images of the regal moth in its pupal stage. Well this past summer I raised some of these guys and took some pictures of the pupae. They’ll be hatching in a few months aswell. Enjoy
Ryan

Hi Ryan,
There is nothing like instant gratification. The ink was barely dry on our request and your photos were in our mailbox. We have been so busy it has taken a few days for us to post them live. Thanks for sending your Regal Moth Pupa images.

Letter 2 – Royal Walnut Moth

 

Can you ID this one ?
Hi
I found this moth in Fairfield Glade, Tennessee, can’t seem to find a match documented so far, can you help?
Thanks
Steve

Hi Steve,
This is a Royal Walnut Moth also known as a Regal Moth. Its caterpillar is the fierce looking Hickory Horned Devil.

Letter 3 – Royal Walnut Moth

 


I took a picture of this moth as it hung on the outside of a bug zapper! Any idea what it is??

The Royal Walnut Moth is the adult of the Hickory Horned Devil

Letter 4 – Regal Moth

 

Citheronia regalis
My name is Kristine and I am from Columbia, Maryland. I found this moth right outside of my door a few weeks ago. I looked at the pictures of moths on your website and happend upon one submitted by a Jeremy in Columbia as well. It also happend to be the same species of Moth that I saw. I thought it was funny and I wondered if he lives somewhere in my apartment complex. Anyway here is the pic! Thanks!
Kristine

Hi Kristine,
While we have no way of knowing if you and Jeremy live in the same apartment complex, we can assure you that insects have intricate biological clocks to assure they will be able to successfully mate and reproduce. Mature individuals in the same vicinity will emerge with startling simultaneity, and this is especially critical with Saturnid Moths like the Regal Moth which only lives a few days as an adult.

Letter 5 – Royal Walnut Moth

 

Huge Moth!
Andy

Hi Andy,
This is a Royal Walnut Moth or Regal Moth, the adult form of the Hickory Horned Devil.

Letter 6 – Royal Walnut Moth

 

Virginia Moth and eggs
This moth was found this morning. By lunch we saw the eggs. Can you identify the moth? We saw the same kind last year. It’s about 3 or 4 inches long, really big.
Sheri

Hi Sheri,
The Royal Walnut Moth is also known as a Regal Moth.

Letter 7 – Royal Walnut Moth

 

moth identification help
I guess I send as an attachment. This morning I went out in my backyard and he was on my tomatoe stick . I put some asparagas fern on to the stick and he climbed over on that. He’s very fuzzy.. I am in Roanoke Virginia
Nancy Anderson

Hi Nancy,
The Royal Walnut Moth or Regal Moth is the adult form of the Hickory Horned Devil.

Letter 8 – Royal Walnut Moth

 

Moth identification
Hello,
I wondered if you could tell me what moth this is? It was approx. 3 1/2" long Thank you
Collene
Western North Carolina

Hi Collene,
This Royal Walnut Moth is sometimes called the Regal Moth.

Letter 9 – Royal Walnut Moth

 

cecropia moth?
Hello! My kids and I recently came across this moth on the side of a local building. I have attached two photos. One of which contains my seven-year-old’s hand for scale. I am wondering if this is a Cecropia Moth. We live on Maryland’s Eastern Shore.
Thank you,
The Shenals

Dear Shenal Family,
This is a Royal Walnut Moth or Regal Moth, not a Cecropia Moth.

Ohh, I’ve only just seen that you have about a million pictures of these on your site. Sorry. I’ll look harder first, next time.

Letter 10 – Royal Walnut Moth

 

Regal Moth?
Hello bugman,
first of all i think your website is awesome. I found this moth (I think it is a Regal moth) at work right after i got off last night(July 15th) I live in Seymour, Tennessee, and i work just 5 minutes down the road. Anyway, I hope you can use this picture! God Bless!
Michael Davis

Hi Michael,
You are correct. The Regal Moth is also known as the Royal Walnut Moth.

Letter 11 – Royal Walnut Moth

 

Beautiful Moth
I can’t tell you how many times my kids have brought in some bug and had me look it up on your site. It is really a wonderful resource for parents and kids exploring the insect world in their backyards. Thank you so much for keeping the site up and running, it is always our first stop when researching a new found critter. I’m not sure what type of moth this is, I haven’t searched the site yet, but it was so pretty the kids insisted that I take pictures and send them to Whatsthatbug.com . I have loaded them into photobucket you may use them if you would like. If you want the actual file in jpg format I can send that as well. Enjoy and put them to use if you need them!
Elaine

Hi Elaine,
We are guessing that by now you know that this is a Royal Walnut Moth or Regal Moth, Citheronia regalis, because we just posted a photo of two adults on a fence post yesterday. We are happy to include your photo on our site as well and hope your children enjoy seeing their moth online. We eagerly await getting our first yearly photos of the caterpillar, the Hickory Horned Devil, beginning in mid to late August and peaking in September.

Letter 12 – Royal Walnut Moth

 

Need Help IDing a Moth
My aunt found a very pretty and large moth in her backyard. We tried finding the type online but its a hard search since i know absolutely nothing about them. I attached a few photo’s for you. thanks for all your help.
Trevor.

Hi Trevor,
This is a Royal Walnut Moth or Regal Moth, the imago of the Hickory Horned Devil.

Letter 13 – Royal Walnut Moth

 

Moth Identification Help
Hello, I found your site tonight after seeing an unusual (what I assume to be a moth) bug that sparked my interest and I hope you can help me since my research turned up nothing and I am still curious. It was found outside under my porch light at about 11pm in Alpharetta, Ga. Thanks,
Jon

Hi Jon,
This is a Royal Walnut Moth or Regal Moth. Perhaps, come September, you will be lucky enough to see its amazing caterpillar, the Hickory Horned Devil.

Letter 14 – Regal Moth

 

Bright red and yellow moth in FL!
My friend in North FL found this enormous moth in her garden. Neither she nor I can find any identification for this gorgeous creature on the internet. I was hoping you could help!! What on earth is this thing?? It squirted yellow goo at her when she tried to relocate it to a safer part of her yard. Weird and cool moth!

This beauty is a Royal Walnut Moth or Regal Moth, the adult form of the frightening, but harmless Hickory Horned Devil Caterpillar.

Letter 15 – Royal Walnut Moth

 

Bugman:
My son found a very large caterpillar several months ago. We kept it and watched it make its cocoon. It just came out of the cocoon this morning. Here is a picture. Please tell me what kind it is. Sorry I didn’t take a picture of the caterpillar or cocoon. Thanks,
Tom Pace

Hi Tom,
This gorgeous moth is known as the Royal Walnut Moth or Regal Moth. The striking caterpillar is called a Hickory Horned Devil. We get numerous moth and caterpillar photos, but we are sadly lacking in a pupa image.

Letter 16 – Royal Walnut Moth

 

Large Spotted Moth
Fri, May 15, 2009 at 10:24 PM
This month (May), we found this large moth on our backyard fence in the piney woods of East Texas. The wings were tan, with orange stripes and yellow spots. The body was large and orange. The entire moth was as large as the palm of my hand. My neighbor tells me she’s seen these around before, but I had never seen one.
Cheryl
East Texas (Lufkin)

Royal Walnut Moth
Royal Walnut Moth

Hi Cheryl,
This is a lovely Royal Walnut Moth or Regal Moth.  The caterpillar is the equally impressive, but frightening, though harmless, Hickory Horned Devil.

Letter 17 – Royal Walnut Moth

 

Big red/white(yellow?) moth
Thu, Jul 2, 2009 at 9:22 AM
Hi! I found this moth this morning hanging out in my yard. I was wondering if anyone had any ideas of what it could be? thanks!
Danielle
Charlotte, NC

Royal Walnut Moth
Royal Walnut Moth

Hi Danielle,
This beauty is a Royal Walnut Moth or Regal Moth.  In about September, we will begin receiving identification requests for its spectacular caterpillar, the Hickory Horned Devil.

Letter 18 – Regal Moth

 

Giant Orange Butterfly
July 16, 2009
I found this bug sitting on the ground at my apartment. It is about 2 or 3 inches long. The pictures I took pretty much explain everything else. Thank you!
Katie
Cary, NC

Regal Moth
Regal Moth

Hi Katie,
This is a Regal Moth or Royal Walnut Moth, not a butterfly.  The Regal Moth only lives a few days as an adult and it does not feed.  It mates and dies shortly after.

Letter 19 – Regal Moth blocks Handicap Entrance

 

Great Site I found my answer
July 24, 2009
I found this on the help button at the gas station on my way home from work yesterday. I’ve been searching for a couple hours to find what kind of moth this is. I was very intrigued with this, as I am will all critters.
After finally finding your site, I found this is a Regal Moth. It was very interesting to read about my find.
Sheila Mc
Griffin, GA

Regal Moth affects ADA Compliance
Regal Moth affects ADA Compliance

Hi Sheila,
Thanks for your kind letter.  Your identification of a Regal Moth or Royal Walnut Moth is correct.  We hope the ADA Compliance Folk at the gas station don’t catch wind of this situation.  We would hate to hear that measures will be taken against moths because this individual is blocking the handicap call button.

Letter 20 – Regal Moth

 

colorful, large moth?
July 5, 2010
We found this bug in Tennessee outside on our front porch. At first we thought it may be a butterfly, but looks more like a moth.
R Hallums
Clarksville, TN

Regal Moth

Dear R Hallums,
Your speculation that this is a moth is correct.  It is a Regal Moth or Royal Walnut Moth, and it is the adult form of the Hickory Horned Devil, the largest North American caterpillar.

Letter 21 – Regal Moth

 

Subject: Moth
Location: June 17th, Cincinnati, Ohio
June 17, 2012 4:58 pm
I was on the back deck of my house cleaning and noticed this bug. I thought it was a moth of some sort, and not knowing many types of moths, wondered if you would know what type it is/
Signature: Hi

Regal Moth

Dear Hi,
This is a Regal Moth or Royal Walnut Moth.  Your photo does not really do it justice.  The appearance of a Royal Walnut Moth in late spring or early summer means that you may get a Hickory Horned Devil sighting in late summer or fall.  The Hickory Horned Devil is the caterpillar of the Royal Walnut Moth.  This is our first sighting report this year of this beautiful moth.

Letter 22 – Prepupal Hickory Horned Devil

 

Subject: What is this bug?
Location: Marietta, GA
September 6, 2012 2:46 pm
This bug was found where my husband works in Marietta, GA. He took the picture today (Sept 6th) and they work in an industrial park near a small lake, trees, pine straw, etc. We have no idea what it is, can you help?!?
Signature: Ashley F.

Prepupal Hickory Horned Devil

Hi Ashley,
This caterpillar is commonly called a Hickory Horned Devil, and its shape has been altered because it is prepupal, meaning it is about to transform into a pupa.  It appears to be on a hard surface, indicating it was unable to find a place to dig prior to pupation, which is the typical progression of events.  Hickory Horned Devils have been compared to Chinese Dragons by our readers.

Letter 23 – Regal Moth

 

Subject: Moth?
Location: Irmo, SC
July 24, 2016 7:12 am
My neighbor found this in her house last night and promptly threw it back outside! What is it??? Any idea?
Signature: Frances O’Toole

Regal Moth
Regal Moth

Dear Frances,
This beauty is a Royal Walnut Moth or Regal Moth, the adult form of the Hickory Horned Devil caterpillar, arguably an even more impressive creature.  We are sad that our first report this year is a dead individual as they are so much more impressive while living.  Regal Moths only live a few days, so this individual may have actually died of old age.

It wasn’t dead yet…. they captured it in there house and put it back outside…

Letter 24 – Regal Moth

 

Subject: Regal Moth
Location: Hocking Hills, Ohio
July 30, 2017 1:24 pm
On our weekend stay in the hills of South East Ohio we had this visitor outside of our cabin. Thanks to your site, I can see it is a Regal Moth. Pretty wild looking! Unfortunately it appears it was on its way out, it couldn’t fly, it was just flapping its wings repeatedly.
Signature: Mark

Regal Moth

Dear Mark,
Thanks for adding your lovely image of a Regal Moth or Royal Walnut Moth to our archives.

Authors

    by
  • Bugman

    Bugman aka Daniel Marlos has been identifying bugs since 1999. whatsthatbug.com is his passion project and it has helped millions of readers identify the bug that has been bugging them for over two decades. You can reach out to him through our Contact Page.

  • Piyushi Dhir

    Piyushi is a nature lover, blogger and traveler at heart. She lives in beautiful Canada with her family. Piyushi is an animal lover and loves to write about all creatures.

4 thoughts on “What Do Hickory Horned Devils Eat? A Friendly Guide to Their Diet”

    • Yes. It should be exposed to weather conditions so that the adult moth emerges at the appropriate time to find a mate and procreate.

      Reply
  1. I live in Maryland on the Chesapeake Bay. This is the first time in my 62 years that I have ever seen a regal moth. There are about 20 of them flying around my place of business.

    Reply

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