Buck Moth Caterpillar: All You Need to Know for Safe Encounters

The buck moth caterpillar is a fascinating creature with some unique features.

These caterpillars are known for their stinging spines, which can cause painful reactions in humans.

The life cycle of the buck moth starts when adult moths lay their eggs on host trees such as oaks or willows.

Buck Moth Caterpillar

Caterpillars emerge, feeding on the leaves and growing through several stages before reaching adulthood.

It’s crucial to understand some key aspects of the buck moth caterpillar, including how to identify them and handle any potential encounters safely.

Buck Moth Caterpillar Basics

Identification

The Buck Moth Caterpillar (Hemileuca maia) is a type of larva that evolves into the Buck Moth. It has a distinct appearance:

• Black body with white spots
• Long, gray spines with venom
• A resemblance to an oak twig, which aids in camouflage

These caterpillars can be confused with Nevada Buck Moth Caterpillars, but the latter has a lighter background color¹.

Life Cycle

The Buck Moth Caterpillar undergoes several stages:

1. Eggs: Laid on oak trees in clusters
2. Larvae: Hatch and grow while feeding on oak leaves
3. Pupal stage: Form cocoons and transform into adults
4. Adult moths: Emerge and reproduce

These moths typically have one generation per year².

Adult Buck Moth

Habitat and Distribution

Buck Moth Caterpillars inhabit various parts of the United States, including:

• Maine³
• Texas⁴
• Wisconsin
• Kansas

Their preferred habitats are oak trees, especially:

• Scrub oak
• Live oak
• Water oaks⁵

The larvae live on and consume these trees’ foliage, making them an essential part of their habitat.

Physical Characteristics

Stinging Spines

Buck moth caterpillars have stinging spines that are filled with venom.

When touched or threatened, these spines can release venom and cause a painful sting to humans and predators.

The venom glands of buck moth caterpillars are located at the base of their spines.

The severity of the sting varies depending on the amount of venom released. Symptoms of a sting may include:

• Immediate pain and redness at the sting site
• Swelling that spreads to nearby lymph nodes
• Small hemorrhages due to venom’s effects on the skin

Buck Moth Caterpillar

Adult Moth Features

When transformed into an adult moth, buck moths display unique features such as:

• A wingspan of 1-1.5 inches, with females being larger than males
• Feathery or saw-edged antennae, a distinguishing characteristic of moths

Comparing buck moth caterpillars to adult moths:

Stings and Medical Concerns

Sting Reactions

Buck moth caterpillar stings can cause sudden stinging, redness, and swelling in the affected area. Spines have a toxin gland at the base, which is released when they break off into the skin¹.

The pain from the sting can spread to nearby lymph nodes, and the swelling and redness can last over a week². In some cases, small hemorrhages may occur where each spine has stung³.

Allergic Reactions and Anaphylaxis

Most people experience mild to moderate symptoms from a buck moth caterpillar sting.

However, severe allergic reactions (anaphylaxis) to the venom are rare⁴.

If you know you are allergic to stinging caterpillars, it’s essential to avoid contact with them and carry an epinephrine auto-injector (EpiPen) as a precaution.

Buck Moth Caterpillar

Common symptoms of an allergic reaction to stinging caterpillars include:

• Itching
• Burning sensation
• Contact dermatitis
• Severe itching

First Aid and Treatment

If you are stung by a buck moth caterpillar, the following first aid steps can help alleviate the symptoms:

1. Use adhesive tape or a sticky brush to remove any remaining spines from the skin⁵.
2. Apply a paste of baking soda and water to the affected area to help neutralize the venom and soothe the sting⁶.
3. Take over-the-counter antihistamines and apply hydrocortisone cream to reduce itching and inflammation⁷.

When to seek medical attention:

• Difficulty breathing
• Rapid heart rate
• Facial swelling
• Shock

If you experience any of these severe symptoms after being stung, seek immediate medical attention, as they could indicate anaphylaxis.

Prevention and Control

Natural Control Methods

Buck moth caterpillar infestations can be managed through various natural methods:

• Introducing predators: Birds, such as chickadees and sparrows, feed on caterpillars and help control their population.
• Hand removal: If the infestation is limited, you can wear gloves and carefully remove the caterpillars from the host plants.
• Caterpillar-resistant plants: Planting species that buck moth caterpillars don’t favor can reduce the chance of infestation.

Chemical Control Methods

Pesticides can be used to control buck moth caterpillars if necessary:

• Bacillus thuringiensis (Bt): This bacterium is most effective on young caterpillars and can be applied to leaves as they feed on them. More information on Bacillus thuringiensis
• Sevin: An alternative insecticide that can provide adequate control of the caterpillars.

Buck Moth Caterpillar

Monitoring and Maintenance

Keep an eye on potential host plants, such as live oaks, and oak twigs. Eggs are laid in clusters during fall, so regular inspections can prevent infestations. Some signs of an infestation include:

• Growth stages: Notice changes in caterpillar size and appearance to estimate their growth stage.
• Migrating: Caterpillars moving from host plants towards lawns or buildings can indicate an infestation.
• Seasonality: Infestations tend to occur in September, so be extra vigilant during this time.

To minimize the risk of being stung by the caterpillar’s stinging hairs, wear gloves when handling infested plants and use an ice pack to reduce the swelling if accidentally stung.

Conclusion

The Buck Moth Caterpillar, a unique member of the insect world, is renowned for its stinging spines, which can cause discomfort in human encounters.

Predominantly found in regions stretching from Florida to Maine and westward to Texas and Wisconsin, these caterpillars thrive in oak-rich environments.

While their stings can be painful, understanding their life cycle, identifying features, and habitats can help in ensuring safe interactions.

As with many creatures, knowledge and awareness are key to coexisting harmoniously.

Reader Emails

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

Letter 1 – Buck Moth Caterpillar

Hemileuca nevadensis – Nevada Buck Moth Larvae?
Location: Mission Trails Regional Park, San Diego County, CA, USA
June 19, 2011 11:58 pm
We found several of these caterpillars feeding on wild Willow trees (Salix lasiandra) along the San Diego river in Mission Trails Regional Park. The caterpillars are venomous and will give a painful red rash if handled.

We have had these caterpillars for 2 weeks now at home, they seem to be slow growing and slow to progress to the different instars. I have provided them with fresh Salix every day to feed. I believe they may be some form of Buck Moth but have been unable to find the exact species.

These seem to have a brighter color and more mottled (not speckled) coloring than the H. nevadensis but not sure?
Signature: Kind Regards, Christine

Hi Christine,
Thanks for your comments on our previous posting of this Buck Moth Caterpillar and also thank you for submitting your photos.  Bill Oehlke has indicated that despite the color variation, they are Hemileuca nevadensis.  Caterpillars frequently exhibit color variations.

Letter 2 – Juno Buck Moth Caterpillar

Photographed in the Mojave
April 8, 2010
Looking for the name of this beetle and the caterpillar photographed in the Mojave near Joshua Tree NP.
John
Mojave Desert, Calif.

Dear John,
Your caterpillar is a Juno Buck Moth Caterpillar, Hemileuca juno, which is described on BugGuide as:  “early instars all black with branched spines arising from tubercles on all segments; final instar densely speckled with white, giving overall grayish appearance, except for reddish tubercles.”  BugGuide also indicates it is found from 

“New Mexico to southern California, south into western Mexico” and the habitat is “desert scrub and mesquite woodlands; adults fly during the day but are also active at night and come to light.”  Finally, “adults fly from September to December larvae from April to June.” 

We do not like posts with more than one species, so if you want us to take the time to identify your beetle (yes our research does take time) please resubmit the photo with more information.

Letter 3 – Buck Moth Caterpillar Aggregation

Possible Buck Moth?
Location: Meaux, Louisiana
March 21, 2012 3:34 am
Found a large circle of caterpillars at the base of a water oak in Meaux, LA. Pretty bizarre to watch, especially as they moved out of the circle and up the tree. A friend of mine pointed me to a Buck Moth identification on your site – and that appears likely to be what they are. Thanks!

About 5/20/2011, we had a bunch of moths swarm the outside of the house. My guess is that they’re the same and I’ll have moths galore in 2 months and some pretty bare oak trees. Do they look like the same to you?

More pics at http://goo.gl/oOA22 – welcome to use any of them as you wish (sadly, the moth pics aren’t very good at all – but I guess I’ll get another chance).
Signature: Mike

Hi Mike,
We concur with your identification of these Buck Moth Caterpillars, Hemileuca maia, and there is a nice matching photo on BugGuide, though they do not have any images that document the interesting formation the caterpillars make when they aggregate.  These social caterpillars also have protective spines that will produce an irritating sting if they are carelessly handled.  That is probably a deterrent to predators like birds that swallow caterpillars whole.

The moth photo you provided is not a Buck Moth.  Rather it is a Salt Marsh Moth, one of the Tiger Moths.

.

Letter 4 – Buck Moth Caterpillars

Trying to Identify….
Location: Slidell Louisiana
March 31, 2011 8:15 pm
This cluster of black caterpillars was on my oak tree & I cant figure out what its name is. Any Help would be appreciated.
Signature: Thank You Karen

Hi Karen,
Though your photo does not have much detail, we believe that based on the general appearance of the caterpillars, their communal feeding, and the host tree of Oak, that these are Buck Moth Caterpillars, Hemileuca maia, based on photos and information posted to BugGuide.  Handle Buck Moth Caterpillars with caution as they are a stinging species.

Letter 5 – Nevada Buck Moth Caterpillar

What is this bug?
Location: San Diego California
June 21, 2011 11:12 pm
Hi, I was wondering if you could identify this catipillar
Signature: Robert Ramirez

Hi Robert,
This is now the third report we have gotten in the past few weeks that there are unusually large numbers of Nevada Buck Moth Caterpillars, Hemileuca nevadensis, in the San Diego area this year. 

See here and here for additional photos and information.  Please do not handle Nevada Buck Moth Caterpillars or any related species as the spines can cause a nasty contact dermatitis.

Letter 6 – Newly Emerged Buck Moth

Subject: Orange/black moth
Location: Baton rouge, La
December 12, 2013 12:23 pm
Crazy looking moth on my window sill in Louisiana.
Signature: Brad

Hi Brad,
Your moth is a Buck Moth in the genus Hemileuca, and they typically fly during the autumn where then are encountered in wooded areas by deer hunters.  We found an article Louisiana State University Agricultural Center because of the large numbers of Buck Moths last December in Baton Rouge. 

We found the article to be a bit alarmist, though it is true that large numbers of moths will mean more Buck Moth Caterpillars in the spring.  It is also true that Buck Moth Caterpillars should not be handled because of the spines which could sting folks who handle the caterpillars carelessly.  We believe your Buck Moth is Hemileuca maia, and it has recently emerged from the pupa, so its wings haven’t yet properly expanded.

Thanks for the speedy reply. I’ve lived in Louisiana forever and have never noticed one before, but I am certainly familiar with the stinging caterpillar.
Brad

Letter 7 – Buck Moth Caterpillar

caterpillar ID
Hi there,
Would you be able to ID this for me? I found it at Goose Lake in the campground on Hwy 24, just outside of Little Fort, British Columbia. Thanks very much.
Jody Foster

Hi Jody Foster,
This is some species of Buck Moth Caterpillar in the genus Hemileuca, but we are not certain of the species. BugGuide has images of caterpillars.

Update: (12/14/2007) your recent Hemileuca photo
Hi, I was looking at your site today and saw the photo of the Hemileuca photo from British Columbia dated: 12/13/2007. I think the species would be one of the following: Hemileuca eglanterina eglanterina Hemileuca hera Hemileuca nevadensis Hemileuca nuttalli These are the only Hemileuca spp. found in British Columbia. I’m not sure of the exact species but I thought I’d narrow it down to these four species.
Ryan

Letter 8 – Buck Moth Caterpillar

Unidentified caterpillar from West Palm Beach, Florida
Hello there,
I hope you can help me identify this caterpillar. I was hiking through a Florida scrub natural area in Boca Raton and came across hundreds (maybe thousands) of these guys tearing into the local scrub oak trees. They really liked the new growth! They were only found on the oaks – so they are very specific. They also sting! What are they?
Ann Mathews
Environmental Analyst
Palm Beach County
Dept. of Environmental Resources Management

Hi Ann,
This is a Buck Moth Caterpillar. Visually, it matches the New England Buck Moth Caterpillar, Hemileuca lucina, that we found on BugGuide. Oak is the food plant. The map we found does not list the range as far south as Florida. A related species, the Eastern Buck Moth, Hemileuca maia, is found in Florida, but the caterpillar looks different than your specimen. It also feeds on Oak. At any rate, we are sure of the genus and the fact that it is a Buck Moth.

Letter 9 – Buck Moth Caterpillar

Really BIG caterpillar
Dear Bugman,
I live in Appomattox, VA, and we saw this caterpillar on the trunk of an oak tree. We don’t see it at night, but we have seen it every morning in the same place. It is very large–about 3 1/2 inches in length, and about 1/2 inch in diameter. I looked through your 9 pages of caterpillars, but nothing looked like it. It looks like it would sting. I love your site!!! Best regards,
Nina Eagle

Hi Nina,
We found your caterpillar on BugGuide. It is an unidentified Buck Moth Caterpillar in the genus Hemileuca. It was found in Texas, also on an oak tree.

Letter 10 – Buck Moth Caterpillar

Subject: Mourning Cloak Caterpillar?
Location: Lebanon, TN
May 23, 2012 9:34 am
Mr. Bugman,
I found this caterpillar at the park and my mom says it might be a mourning cloak caterpillar. Do you think she is right? That’s me holding it on a stick.
Thanks!
Jovie
Signature: Jovie

Hi Jovie,
The the Mourning Cloak has a black spiny caterpillar, we believe this is a Buck Moth Caterpillar, Hemileuca maia, which you may verify by comparing your caterpillar to this image on BugGuide.  It is also noted on BugGuide that:  “Caterpillar is variable, with base color ranging from black to almost white.

Thorax and abdomen densely flecked with white dots. Many-branched spines can deliver a painful sting” and “Larvae feed on Oaks, Quercus, especially Scrub Oak, Quercus ilicifolia. Wanders in later instars.” 

This late instar was probably wandering to find a good place to pupate.  By comparison, the Mourning Cloak Caterpillar has a row of red spots along the back that is missing from your caterpillar.  

Letter 11 – Buck Moth Caterpillar

Subject: Caterpillar in utah
Location: Hwy 95, south of Hite
May 16, 2013 10:40 am
We found a strange caterpillar in the desert of southern Utah on Hwy 95 south of the town of Hite on the Colorado river. We looked in the books and on line and could not find the little guy! He was about 3 inches long hiding in some Mormon Tea plant.
Signature: Chris

Hi Chris,
This spiny guy is a Buck Moth caterpillar in the genus Hemileuca.  Here is a similar looking individual from BugGuide that is identified as Hemileuca griffini and Bugguide only has sightings from Utah.  According to the Butterflies and Moths of North America: 

“Habitat: High desert scrub.  Range: Southern Utah south to central Arizona, west to southern Nevada.”  The site also notes:  “Populations should be inventoried and monitored to determine conservation status and impact of grazing on habitat.”  BugGuide also has these remarks: 

“This species is considered to be threatened, due to its restricted range, and possible threats to its habitat from grazing of livestock. (4)  Like other species in this genus, H. griffini caterpillars have venomous spines that cause a painful sting.”

Letter 12 – Buck Moth Caterpillar

Subject: Can you ID this caterpillar?
Location: California, MD
July 21, 2014 1:25 pm
The best I can guess is that it’s a type of brush footed butterfly larva. I’d love to know what type of adult it will become and what it feeds on. The kids would like to hatch it and then release it.
Signature: Laura in SoMD

Hi Laura,
While many Brushfooted Butterfly Caterpillars have spines, including the Mourning Cloak Caterpillar, this is actually the caterpillar of a Buck Moth, and considering your location, it is most likely Hemileuca maia, based on this BugGuide image.  Handle the Buck Moth Caterpillar with care as contact with the spines may result in a painful sting.

The adult Buck Moth, which gets its name because it is usually on the wing very late in the fall during deer hunting season, is a lovely moth.  By the way, we were unaware that there were any cities named California.

Thank you for the helpful ID. Since you mentioned it, California is just south of Hollywood,  MD.

Letter 13 – Buck Moth Caterpillar

Subject:  Spiky caterpillar
Geographic location of the bug:  New York State
Date: 09/07/2019
Time: 01:07 PM EDT
Your letter to the bugman:  Hello,
This was taken today in New York State.  I’ve searched trying to indenting this one but it has me stumped. Any info would be much appreciated. Thank you!
How you want your letter signed:  Kat

Dear Kat,
Based on this BugGuide image, your caterpillar appears to be that of a Buck Moth, Hemileuca maia.  According to BugGuide:  “Caution, caterpillars can inflict painful sting.”

Letter 14 – Buck Moth Caterpillar, but which species???

Subject: caterpillar
Location: Williams, Oregon 97544
July 24, 2013 4:06 pm
I saw this guy at a open pollinated seed farm. Do you know what it is?
Signature: applegatetech

Hi applegatetech,
This is a Buck Moth Caterpillar in the genus Hemileuca, and all members of the genus have stinging spines.  According to the World’s Largest Saturniidae website, there are four species of Buck Moths reported from Oregon, and all have similar looking caterpillars.  BugGuide provides this image of an Elegant Sheep Moth Caterpillar, Hemileuca eglanterina, and BugGuide indicates the food plant is: 

“Larvae feed on trees, shrubs, esp. Rosaceae, such as rose (Rosa), Hawthorn (Crataegus), cherry (Prunus), etc. Also willow (Salix), aspen (Populus), birch (Betula).”  Apple trees are in the rose family, so there is strong evidence this might be the caterpillar of an Elegant Sheep Moth.  According to BugGuide, the Hera Buck Moth, Hemileuca hera, has “Caterpillars feed on basin big sagebrush (Artemisia tridentata) and sand sagebrush (A. filifolia),” so unless sage was present on the farm, we can eliminate the Hera Buck Moth. 

According to BugGuide, the caterpillars of the Nevada Buck Moth, Hemileuca nevadensis, feed on “Alder and willow” so again, if those trees are not on the farm, the Nevada Buck Moth can be eliminated.  BugGuide has photos of Hemileuca nuttalli, but does not provide any information.  The World’s Largest Saturniidae Site provides this list of food plants:  “Birchleaf cercocarpus, Antelope bitter brush, Firethorn, Snowberry, Mountain snowberry” so we are also confident eliminating that possibility. 

Indications are good that this is the caterpillar of an Elegant Sheep Moth, a lovely and highly variable species. Perhaps if you have an opportunity to photograph an adult moth, you can send the photos to our attention with the subject line “Elegant Sheep Moth” because we would love some newer photos for our archive.

Letter 15 – Correction: White Rayed Patch Caterpillar, NOT Pine Moth Caterpillar from Mexico

Ed. Note:  28 February, 2016
We received notice from Peculiarist that the same caterpillar was submitted for twice for identification.  The correct identification is most likely a White Rayed Patch caterpillar.

Subject: Caterpillar
Location: Cuernavaca Mexico
February 17, 2016 12:02 pm
Hi,
I took this photo on October 2014 in Cuernavaca, Mexico. I think it may have been on milkweed, but I’m not a hundred percent sure about that. I’d appreciate any insights.
Signature: Peculiarist

Dear Peculiarist,
We believe this is a Buck Moth Caterpillar in the genus Hemileuca, but we have not had any luck locating any matching images of Mexican species with such dark coloration with yellow speckles.  We will contact Bill Oehlke to get his opinion.

Bill Oehlke Responds
Daniel,
I am pretty sure it is one of the Coloradia species, and the only Coloradia I have for Morelos is Coloradia euphrosyne. Unfortunately I d o not have an image for comparison, but I will tentatively post this image to that page. As always I request name of photographer and permission to post.
Bill

Bill Oehlke amends his original response
Daniel,
Elevation and date might also be helpful if you can obtain that info. Euphrosyne are known from elevations around 2000m and are thought to be pine feeders although the larval stage has not been documented to my knowledge.
Bill

Peculiarist writes back.
Thanks for the identification! I gladly give you permission to use the image for the site.
And thanks for the site, it’s very helpful to me, as I try to figure out what’s in my garden.
James

Update from Peculiarist:  February 27, 2016
Hi Daniel,
As I was updating my page I noticed that this is the same caterpillar I sent before (my photo folders are a bit of a mess, and I had this duplicated in another folder), that was tentatively identified as a Pine Moth caterpillar. They do look alike, but I think with the extra information you have in these three photos White-rayed Patch is a more likely match. The food tree matches.
Thanks for your help, and I’ll be more careful in sending the most complete information I can in the future.
James

Letter 16 – Buck Moth Caterpillar, we believe

Caterpillar of Ctenucha multifaria?
June 6, 2010
I collected this caterpillar on a driveway beside a grassy field on June 1. I’m wondering if it might be the larva of Ctenucha multifaria, an extremely colorful day-flying moth. The moth is quite uncommon, so no on-line photos of the larva of that species are available. The caterpillar in the photo is about 10mm long.
Ron Hennessey
Occidental, Sonoma Co., California

Hi Ron,
We were pretty certain that despite no images of Ctenucha multifaria being available, that your hypothesis was incorrect.  We looked at images on BugGuide of the Virginia Ctenucha, and they seem quite different.  We would favor this being one of the Buck Moths in the genus Hemileuca, and there are many that inhabit meadows in California. 

Though the coloration is different, you can see the similarities with the caterpillar of the Elegant Sheep Moth, Hemileuca eglanterina, which is posted to BugGuide.  It looks even more like the caterpillar of Nuttall’s sheepmoth, Hemileuca nuttalli, also posted to BugGuide.

Letter 17 – Buck Moth dead of natural causes

Subject: I swear I didn’t kill it, despite the flyswatter in the photo!
Location: New Orleans, LA
November 21, 2012 9:56 pm
Hi,
I found what I assume is a moth of some sort ALREADY DEAD on my patio 11/21/12. The flyswatter was used to transport it into the light so I wouldn’t crush it with a paper towel.
It was in the mid 60’s when I found it after being in the upper 60’s most of the day. It definitely wasn’t there the night before.
I put it next to a cd for size comparison and also included a closeup of the body and then also the wings.
Thanks!
Signature: Jenn

Hi Jenn,
We were away from the office for Thanksgiving and we are just catching up on some old identification requests and posting the best of them.  This is a Buck Moth, a species we featured in October.  Buck Moths do not feed as adults and they only live for about a week.  We are quite certain this individual died of natural causes.

Thank you so much for the identification and for the ‘not guilty’ verdict!
I’m relatively new to this particular area and had not seen such a large bodied moth anywhere before, unless they were introduced during one of the many times that I covered my eyes while touring the Audubon Insectarium!
I’m now pretty sure that I saw the caterpillar version also on my patio a few weeks back and fortunately had sense enough to steer clear of its threatening spines.

My father will be pleased to know that y’all were able to help me, as it was his suggestion to contact you. I was a bit concerned that I could have an impending invasion of moth aliens and his initial identification of “big freaking moth” was not exactly helpful in calming my worries.
Thanks again!

Since the caterpillars of the Buck Moth are social feeders, we would imagine that there could possibly be years with significant adult moth populations.

Letter 18 – Buck Moth: Harbinger of Autumn

Buck Moth
Subject: Colorful Moth
Location: Orange County, NY, USA
October 7, 2014 8:34 am
I spotted this moth while geocaching. This was on the Shawangunk Ridge in Orange County, NY near an abandoned lead mine on the 6th of October.
The exact location is:
N 41° 26.439 W 074° 34.758
UTM: 18T E 535144 N 4587760
WGS84 datum
Signature: M.Bahlam

Dear M. Bahlam,
This lovely moth is a Buck Moth, Hemileuca maia, and they fly quite late in the year.  The common name Buck Moth refers to their presence during hunting season where they are frequently encountered in the woods.

Letter 19 – Buck Moth we believe

Subject:  Two insects or one?
Geographic location of the bug:  Bend, Oregon
Date: 07/19/2021
Time: 12:00 AM EDT
Your letter to the bugman:  Seen in the evening, July 19, 2021, Bend, Oregon. Nudged it to see if it was two separate bugs but it didn’t separate.
How you want your letter signed:  Julie

Dear Julie,
This is a Moth but we can’t see enough detail to provide you with a definitive species (or family) identification, but we believe this may be a Buck Moth in the genus Hemileuca.  One highly variable species, the Elegant Sheep Moth, is pictured on the Moth PHotographers Group site.  It is also possible this might be a Tiger Moth in the subfamily Arctiinae.

Letter 20 – Buckmoth Caterpillar

Subject: New Otleans caterpillar
Location: New Orleans
May 1, 2016 2:04 pm
We’re walking down a sidewalk in the Garden District of New Orleans and there are tons of these caterpillars falling out of a tree. One got on my friend’s sock and when she pulled it off, she got stung. Any clues what it is?
Signature: Joelle

Dear Joelle,
Thanks so much for resubmitting using our standard form.  It really helps us to format postings correctly.  This is a Buck Moth Caterpillar in the genus Hemileuca, and many caterpillars in the genus look similar.  This is most likely Hemileuca maia, a species found in much of eastern North America. 

According to BugGuide:  “Caution, caterpillars can inflict painful sting.”  Since they were falling from the trees, they are most likely getting ready to pupate.  Adult Buck Moths emerge and fly in the autumn.

Letter 21 – Buckmoth Caterpillar

Subject:  Spikey Caterpiller
Geographic location of the bug:  Southern Ohio
Date: 09/16/2018
Time: 01:38 PM EDT
Your letter to the bugman:  I found this outside of my home in southern Ohio, is this a brush footed Caterpillar? Are they harmful to humans?
How you want your letter signed:  Shane

Dear Shane,
Though there are many spiny caterpillars in the Brush Footed Butterfly family Nymphalidae, we believe your caterpillar is a Buckmoth Caterpillar, Hemileuca maia, based on this BugGuide image.

Letter 22 – Hera Buckmoth

moth
I shot this picture of a moth in Jackson, Wyoming while there on vacation this summer. I have been unable to identify it. Your help would be greatly appreciated.
Dave
Winchester, Va

Hi Dave,
This is a Hera Buckmoth, Hemileuca hera. We found a website with additional information. Just yesterday we posted a photo of a close relative in the same genus, the Sheep Moth. This is a new species for our site and we always get excited when we get new species photos, especially ones as fine as yours.

Letter 23 – Hera Buckmoth

Hera buckmoth
Hi, you people do a fantastic job! Have been looking at your moth postings and did not see this guy whom I believe to be a Hera buckmoth. Photo was taken in sage and grassland north of Lance Creek, WY.
Dwaine

mea culpa
Hi, sorry, I see you do have a photo of the Hera Buckmoth. I was thinking it is a Tiger moth not a Silkworm moth.
D–

Hi Dwaine,
We spent so much time answering your caterpillar queries that we did not realize you sent another letter. We identified one of your caterpillars as a Buckmoth, probably the Hera Buckmoth, and you sent strong evidence that we were correct with these adult moth images.

Thanks for your valuable contribution and we are blushing at your compliments. We are going to repost your caterpillar image with the adult.

Letter 24 – Hera Buckmoth

What kind of moth is this?
August 24, 2009
We found this moth at a lake in northern Wyoming. It has very feathery antennas. White wings with black spots. Its abdomen is white and black striped, with a fuzzy orange head and thorax. My images are not real clear. Thank you.
Allison
northern Wyoming

Hi Allison,
This is some species of Buck Moth in the genus Hemileuca, possibly the Hera Buckmoth, Hemileuca hera.  You can see if the photos posted to BugGuide match your moth.

Letter 25 – Hera Buckmoth

Subject:  Lepodopteran identification request
Geographic location of the bug:  USA, California, 12 km west of Bishop in the Sierra Nevada Mts.
Date: 09/21/2021
Time: 04:23 PM EDT
Your letter to the bugman:  Came across several of these emerging on August 30, 2021.  Just wondering about the identity of this beauty?
How you want your letter signed:  Frank Baele

Dear Frank,
This is one of the Buckmoths in the genus Hemileuca, and we believe it is most likely the Hera Buckmoth, Hemileuca hera, which is pictured on BugGuide where it states:  “Caterpillars feed on basin big sagebrush (Artemisia tridentata) and sand sagebrush (A. filifolia). Adults do not feed.”

Hey Daniel, that is great! Much appreciation.  Frank Baele

Letter 26 – Juno BuckMoth Caterpillar parasitized by Braconid Wasp

My Bug
Hello – I do know my bug is a caterpillar of some sort but what I want to know is what is happening to this creature. I live in south east Arizona and the caterpillar is common here but I have never seen one with the white “larvae” attached to it. It is alive and was perched on a mesquite tree branch when we found it. Do you have any ideas? Thanks you…
Jeannie

Hi Jeannie
Your Juno Buckmoth Caterpillar, Hemileuca juno, which we matched on BugGuide, has been parasitized by a tiny Braconid Wasp that laid her eggs in the caterpillar. The young wasps fed on the caterpillar and then pupated outside. Sadly, the caterpillar will die.

Letter 27 – Longtailed Skipper and Buckeye

butterflys
This was feeding in my yard,can you tell me if it is a butterfly,or a moth…my son says moth..I did not care it was so pretty. thank you,
Sue Moore
Silsbee,Texas

Longtailed Skipper	Buckeye

Hi Sue,
We have combined your two letters together as both images were of butterflies. The one your son thought was a moth is a Longtailed Skipper and the other is a Buckeye.

Letter 28 – Mating Buckmoths: Splendor in the Grass

hemileuca buckmoths?
Scanned your pix to try to ID this mating pair I spotted tangled in the grass at Shohola Lake in northeast PA. Thought you might like the picture — never saw these before. Your site is a national treasure!
Paula K.

Hi Paula,
Your letter cheered us tremendously after a long hard day at work. Not only is your photo of mating Buckmoths quite spectacular, calling our site a National Treasure is one of the nicest compliments we have ever received.

Hello Daniel,
Spreading knowledge and furthering us layfolks’ appreciation of the natural world is truly good work. After years of finding such interesting critters in the field, I can take a creaky digipix, send it to you, and have a whole new corner of the world opened up to me. Who would figure such cute little furry moths came from venomous spiky caterpillers? It’s most helpful knowledge too, should we ever encounter the caterpiller! Thanks again,
Paula K.

Letter 29 – Mating Hera Buckmoths

Bug Love: Hera Buckmoths
August 25, 2009
Hi Lisa Anne and Daniel. As you can imagine, I was quite pleased today to find these mating Hera Buckmoths on the ranch of my friends Bart and Gay Lynn Byrd. I hope you enjoy them also.
The improvements to your site are great 😀
Peace
Dwaine
north of Glenrock, WY

Hi Dwaine,
Thanks so much for sending your awesome photos of mating Hera Buckmoths.  We are copying our webmaster who just spent an entire work week on our site improvements.  We dumped all of our revenue into a new server and we are thrilled with the new found speed.

Letter 30 – Nevada Buck Moth, we presume

Subject: moth in california
Location: riverside county california
October 27, 2013 7:09 am
This cute little moth lives in the san timoteo canyon stream bed. It is only around from late Sept through early November.
Signature: sue mc clure

Dear Sue,
This is a Buck Moth in the genus Hemileuca, and we are nearly certain it is a Nevada Buck Moth, Hemileuca nevadensis, based on its color, markings and location of sighting.  Different species of Buck Moths are found throughout North America, and the common name is a reference to the flight time of the adults, which roughly coincides with deer hunting season in many parts of the country.  You can find additional information on the Nevada Buck Moth on BugGuide.  Though the following information from BugGuide refers to a different species of Buck Moth, we believe it also applies to your Nevada Buck Moth:  “Forewing and hindwing black with narrow white bands. Tip of abdomen red in males, black in females.  Said to fly rapidly at mid-day through oak forests. ”  Those do appear to be oak leaves on the ground in your photograph.

Wow! Thank you so much for getting back to me. Now I will enjoy my little Buckies all the more. They are hanging out not around Oak trees but Cottonwoods in the river bed. They have been very busy this last week- I am thinking perhaps they are laying eggs for next year’s crop. Thank you again for that very quick reply. I have been looking for an answer for 3 years now… I appreciate your time and expertise! sue

Letter 31 – Eastern Comma Caterpillar, NOT Buck Moth Caterpillar

Subject:  Black and yellow spiny caterpillar
Geographic location of the bug:  Clinton, IL
Date: 08/26/2018
Time: 01:21 PM EDT
Your letter to the bugman:  My son and I found this hiking in a heavy wooded area. We have no idea what species it is. We did find Colobura dirce but that’s inky found in Central America. Any help would be appreciated. Thanks.
How you want your letter signed:  Ray and RJ Alvarado

Dear Ray and RJ,
We believe this is a Moth Caterpillar in the subfamily Hemileucinae, possibly a Buck Moth Caterpillar, Hemileuca maia, which is pictured on BugGuide.  The coloration on your individual is different from any other images we have located.  We have requested assistance from Bill Oehlke on this identification.

Bill Oehlke makes correction:
Hi Daniel,
I think it is more likely a butterfly larva from Nymphalidae family.
Bill

Thanks so much Daniel. My son is super excited about finding a color that’s not normal.
Ray

Hold tight Ray.  We are going to have a correction for you.

Correction:  Eastern Comma Caterpillar
Hi again Ray,
After hearing from Bill Oehlke that this was more likely a Nymphalidae butterfly caterpillar, we located an image on BugGuide of an Eastern Comma Caterpillar, Polygonia comma, and then located a second BugGuide image as substantiation.  According to BugGuide: 

“Larvae feed primarily on Hops (Humulus) and Nettles (Urtica, but also False Nettle (Boehmeria), Wood Nettle (Laportea), Elm (Ulmus), and probably other members of families Urticaceae and Ulmaceae.”  Despite having over 26,000 unique posting, this is the first image we have of an Eastern Comma Caterpillar on our site, though we have several images of adult Eastern Commas.

Perfect. Thanks for the follow up and you guys are welcome to use our pics if you’d like.
Ray Alvarado

Letter 32 – Buck Moth Caterpillar

Subject: caterpillar Joshua tree nat. park
Location: Joshua Tree National Park, CA
September 29, 2013 12:53 am
Hi,
I would like to identify this caterpillar. We saw it on 21September at Joshua Tree National Park around noon. It was a ”cool” day with about 85F (after weeks getting over 100F).
It was on the hike to 49 palms Oasis which is in the northen part of the park.
Thank you for your help 🙂
Best
Signature: Viv

Hi Viv,
We believe this is a Buck Moth caterpillar in the genus Hemileuca.  There are several California species including the Juno Buck Moth, Hemileuca juno.

Hi Daniel,
that is so cool. thanks so much for the info.
Your guys rock 🙂
cu
Viv

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 – Bug of the Month October 2012: Buck Moth

Subject: is this some kind of tiger moth?
Location: Francestown, NH
September 27, 2012 5:02 pm
Hi, discovered this moth September 8th while pruning some shrubs/trees in a woodland garden. Seems like this character had just ”hatched” and was drying its wings. Amazing that when I put the branch down on the moss, it instinctively worked it’s way to the end of the branch so it could hang in the breeze to dry, it was gone a few minutes later. I searched hundreds of photos with no luck, although shape and some features were close.
Signature: alf

Hi alf,
Your photo arrived at a very timely moment.  It is the end of the month, and it is time for us to select a new Bug of the Month for October, and your Buck Moth, Hemileuca maia, gets that honor.  Your sighting is also right on time for the Buck Moth’s seasonal appearance.  According to BugGuide they fly “October-November, only to September in north, to December in Florida.”  That coincides with buck hunting season in many parts of the country, hence the common name.  We imagine that Buck Moth are seen flying in the woods when hunters are out trying to bag that trophy.  We frequently post photos of Buck Moth Caterpillars in the summer, but folks should be warned that they have stinging spines.  The Buck Moth Caterpillars feed on the leaves of oak trees.  The Buck Moth genus contains other species, including some that are found in the west, like the Elegant Sheep Moth, but your species has only been reported as far west as Texas, and from Canada in the north to Florida in the south.  Like other members of the Giant Silkmothfamily Saturniidae, Buck Moths have a very short lifespan and they do not feed as adults.  Your photos are positively gorgeous, and they are a marvelous addition to our archive.  As an aside, we have noticed a significant uptick in the number of postings we are making from New Hampshire.  It makes us wonder if there is some reason folks in the Granite State are sending in so many identification requests.

Hi Daniel, thanks for the emails!  Guess I was looking at the wrong spot in the database.   Wow, bug of the month, if nothing else that will make me post more interesting sightings J
I don’t know if any specific reason for the uptick, but I’m sure more people with digital cameras, and the push for more protected land in the rural areas.  We are lucky in that we are surrounded by 600 acres or so of protected land.
Thanks again
alf

Thanks alf,
The uptick is specifically submissions from New Hampshire which have been arriving in a disproportionate number.  How lucky to have 600 nearby acres of open space.  In our Los Angeles neighborhood, we just got an additional 2 acres of black walnut woodland added to our existing 34 acre park, and that is huge in a city where land with a view commands a premium price.