Oakworm Moths: All You Need to Know – Essential Tips & Facts for Curious Minds

Oakworm moths are fascinating creatures that play a significant role in the ecosystem of oak trees. These insects belong to various species such as Anisota senatoria, Anisota stigma, and Anisota virginiensis, with the orangestriped oakworm being the most common among them Oak Diseases & Insect Pests | Home & Garden Information Center. In this article, we will provide essential information about oakworm moths and their life cycle, as well as address common concerns regarding their impact on oak trees.

Oakworm moths primarily thrive in the United States, favoring areas with a high population of oak trees. The larvae, or caterpillars, are known to feed on the leaves of oak trees, causing defoliation in some cases. Interestingly, the yellowstriped oakworm’s pupae can be found residing 50 to 80 mm deep in the soil, where they overwinter for about ten months yellowstriped oakworm – Anisota peigleri Riotte.

Despite their potential impact on oak trees, oakworm moths are not typically considered major pests. While they can cause some damage to the trees they inhabit, most healthy oak trees can recover from these infestations. In the following sections, we will delve into the various species of oakworm moths, their behaviors, and life cycles, while also shedding light on effective ways to manage these moths and maintain healthy oak forests.

Overview of Oakworm Moths

Taxonomy and Classification

Oakworm moths belong to the family Saturniidae and are part of the Lepidoptera order. These moths can be found in various regions across the United States such as California and North Carolina.

Some oakworm species include:

• Phryganidia californica (California oakworm)
• Anisota senatoria (orangestriped oakworm)
• Anisota peigleri (yellowstriped oakworm)

Comparison Table

Oakworm moths are known to be pests on oak trees. Their larvae feed heavily on the leaves of these trees, causing damage and defoliation. In some cases, populations of oakworm moths can reach outbreak levels, leading to severe defoliation and inconvenience to humans due to falling frass (droppings) and large numbers of caterpillars.

It’s important to be aware of the oakworm moths in your region and manage their populations to maintain the health of oak trees and local ecosystems.

Common Species of Oakworm Moths

Orangestriped Oakworm

The Orangestriped Oakworm (Anisota senatoria) is a species of moth that feeds on oak trees. They are mainly found in Eastern parts of North America.

• Features:
  • Black in color with orange stripes
  • Spiked, black hair-like structures on their body

Some examples of their impact include defoliation of oak trees, leading to potential harm to the tree’s health. Despite being considered a pest, these moths are an essential part of the ecosystem as they provide a food source for predators.

Yellowstriped Oakworm

The Yellowstriped Oakworm (Anisota peigleri) is another oak tree pest found in the southeastern United States, such as Florida¹. This species is known for its defoliation of oak trees, specifically laurel, water, and Shumard oaks¹.

• Characteristics:
  • Yellowish-green color with black stripes
  • Hair-like structures on their body

Pros and cons of Yellowstriped Oakworms include their positive role in the ecosystem as a food source for other species, but their defoliation can cause severe damage to oak trees if left untreated.

Comparison Table

Pink-Striped Oakworm Moth

The Pink-Striped Oakworm Moth (Anisota virginiensis), identified by James Edward Smith, is another common oakworm moth species prevalent in several parts of North America². Its distinctive pink striping sets it apart from other oakworm species.

• Features:
  • Dark black color with pink stripes
  • Spiny, hair-like structures on their body

These moths contribute to the oak tree ecosystem as their caterpillars consume foliage, supporting the growth and spread of oak trees around their habitat.

Distribution and Habitat

North America

Oakworm moths, such as the California Oakworm and the yellowstriped oakworm, are found in various regions across North America, including:

• Texas
• Florida
• Eastern North America
• Northeast
• Southern Ontario
• Alabama
• Minnesota
• Great Plains

Regional Variations

Different species of oakworm moths show regional variations:

• California Oakworm: Primarily found along the coast and coastal mountains of California.

• Yellowstriped Oakworm: Commonly found in the southern United States, including Alabama and Florida.

Example:

The orangestriped oakworm is particularly common in South Carolina, where it feeds heavily on oak leaves.

Comparison Table:

Appearance and Physical Characteristics

Moths

Oakworm moths exhibit distinct features:

• Color: Black or dark brown forewings
• Wingspan: Varies depending on species and sex

For instance, the California Oak Moth (Phryganidia californica), has a wingspan ranging from 20-32 mm. However, the Yellowstriped Oakworm Moth (Anisota peigleri) has a larger wingspan, reaching up to 40-70 mm.

Caterpillars

Oakworm caterpillars have unique characteristics as well:

• Color: Green with black head (most species)
• Spines: Sharp, black or yellow
• Subfamily: Ceratocampinae

The California Oakworm Caterpillar is primarily green with a black head and sparse black or yellow spines. Meanwhile, the Yellowstriped Oakworm caterpillar has a green body with yellow and black longitudinal stripes and black spines.

Life Cycle and Development

Stages of Growth

The life cycle of the Oakworm Moth consists of four key stages:

• Egg
• Larva (caterpillar)
• Pupa
• Adult moth

Eggs are laid on oak leaves and hatch into oakworm caterpillars. Caterpillars go through several growth stages, called instars, before they pupate.

Characteristics of oakworm caterpillars:

• Greenish color
• Smooth surface

Development stages:

• 1st instar: hatch from eggs
• Intermediate instars: eat and grow
• Final instar: prepare for pupation

Caterpillars pupate and then emerge as adult moths. There are typically two oakworm generations per year in Northern California, with a third generation sometimes occurring in warmer areas.

Comparison of Oakworm Caterpillar and Other Caterpillars

Behavior and Diet

Feeding Habits

The Oakworm moth is a species of caterpillar that primarily feeds on oak trees’ leaves, especially the California Oakworm. By consuming leaves, these caterpillars obtain essential nutrients and water, aiding their growth.

• Food: Oak tree leaves
• Habitat: Oak trees, particularly along the coast and coastal mountains of California

The diet of the Oakworm moth’s caterpillars can be compared to the Yellowstriped Oakworm, which also consumes oak leaves.

Comparison Table:

Examples of feeding habits include caterpillars chewing on leaves, especially new foliage, and consuming entire leaves when populations are high. In turn, they affect the health of oak trees.

Remember, oak trees provide food and habitat for the Oakworm moth, making their presence vital for maintaining this species’ population.

Infestations and Effects on Trees

Signs of Infestation

• Spongy moth egg masses in clumps of 500 – 1,000 eggs
• Presence of caterpillars
• Brown frass on shrub foliage under infested oak

infestation is indicated by the presence of large numbers of egg masses and caterpillars. Spongy moth females lay egg masses in clumps of 500 to 1,000 eggs, leading to high populations in affected oak trees.

Damage to Oak Trees

• Skeletonize: leaves stripped of soft tissue, leaving veins
• Defoliate: removal of leaves
• Hinder tree growth
• Partial or entire canopy loss

oakworm moths, like the California oakworm, cause significant stress and damage to oak trees by feeding on the leaves and causing damage in two ways:

1. Skeletonizing: Oakworm larvae feed on the parenchyma (soft tissue) of leaves, leaving the veins untouched.
2. Defoliating: Heavy infestations can result in the removal of almost all leaves in the canopy.

Example: When the forest tent caterpillar infestations occur, trees may suffer from extensive feeding damage, leading to overall stress and hindered growth.

The combination of skeletonizing and defoliating can lead to the weakening of tree growth, as well as partial or entire canopy loss in severe cases. Furthermore, other pests might take advantage of the compromised tree, leading to further issues.

Control and Management

Prevention Methods

• Natural predators: Encourage birds and beneficial insects that feed on oakworms and their eggs.
• Visual inspection: Regularly check oaks for signs of infestation, such as larvae, eggs, or frass.
• Pruning: Trim branches to remove caterpillars and their webs.
• Pheromones: Use pheromone traps to monitor moth population and reduce mating.

Treatment Methods

• Bacillus thuringiensis (Bt): Apply Bt on affected trees to target caterpillars without harming natural predators.
• Chemical control: Use insecticides containing active ingredients such as spinosad, carbaryl, or acephate. Safety is crucial; always follow instructions.
• Manual removal: Physically remove tent caterpillars and their webs with gloved hands or a brush.

Comparison Table:

Pros of Prevention Methods:

• Environmentally friendly
• Encourages natural predators

Cons of Prevention Methods:

• May not fully eradicate oakworms
• Requires consistent monitoring

Pros of Treatment Methods:

• Effective in eradicating oakworms
• Multiple methods available

Cons of Treatment Methods:

• Chemical control has environmental impact
• May harm beneficial insects when using chemicals

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 – Newly Metamorphosed Oakworm Moth

what is this bug?
January 19, 2010
this is a florida find. we have no idea what it is other than a moth.
plaes and thank you
florida

This is a newly metamorphosed Oakworm Moth in the genus Anisota.  The wings have not yet expanded to their full size.  Sometimes, this fails to happen and the adult moth will never be capable of flight.  BugGuide has a nearly identical photo, and there is also considerable information on the genus posted to BugGuide.

Letter 2 – Orange Striped Oakworm

Orange Striped Oakworm
Location:  Near Maumee, OH
August 27, 2010 8:13 am
While hiking on nature trails near Maumee, OH, we came across many dozens of these caterpillars on the ground. Most of them had been trampled by hikers, joggers, and Park vehicles, (ecchhhh–what a mess!), though some were still alive and crawling. This specimen was quite alive and about 2.5 to 3” long.
I had never seen this type of caterpillar before, and after investigating online, believe it to be an Orange Striped Oakworm. I am assuming that so many were on the ground at once, because it was time for them to burrow into the ground and pupate.
Many of the Buckeyes, Hickory and young Oak trees had their leaves decimated– and again I’m assuming it could have been a result of the Oakworm’s feeding. Interestingly, the mass carnage of both caterpillars and leaves was very localized, occuring in an area of about 100 yards.
Chris O.

Dear Chris,
We agree that this is an Orange Striped Oakworm, Anisota senatoria, and there is considerable information about the species posted on BugGuide.  To the best of our knowledge, the caterpillars do not feed on buckeye or hickory, but your observation on the defoliated trees is very interesting.

Letter 3 – Orange Striped Oakworms

Caterpillars Second submission, once again from Hickory, NC. These caterpillars were all over town a week ago, but now they seem to either died or cocooned. Please identify and provide some background. Thanks!
Gene Annas

Hi Gene,
The website Caterpillars of Eastern Forests has a photo which identifies your caterpillar as an Orange-striped Oakworm (Anisota senatoria). The site says it is: “Charcoal black with orange-yellow stripes that fade appreciably in prepupal individuals. Head black. Second thoracic segment with long, black spinulose horns. Abdominal spines relatively small. Gregarious in early instars, then solitary. Occasionally reaches outbreak densities. One related species occurs in southern Ontario, and another in Florida and Georgia. Food: oaks and chestnuts. Caterpillar: August to October; 1 generation.” The adult moth is a pretty orange color.

Letter 4 – Pink Striped Oakworm Moth

Subject: Pregnant Red Moth, Need Help to Identify
Location: Sanford, Florida
September 8, 2012 8:55 pm
This moth attached itself to my car at the gas station in Sanford, Florida today. It rode home with us and my daughter thought it was pretty so we decided to put it in a jar with some air holes in the top. We added some water in a bottle cap and some sections of a clementine broken apart. The moth flapped around for a few and then stopped up against the side of the jar and started laying eggs. Now we are trying to figure out how long before the eggs hatch and how we can best take care of the mother moth to keep her alive. My daughter wants to take her to school for show and tell on Monday, but if the larvae will crawl out of the airholes and into our home, we will probably just let the moth go. Please help so we can make sure to take the best care of mama moth.
Signature: -Chris Pollice

Hi Chris,
This is either a Pink Striped Oakworm Moth, Anisota virginiensis, or another member of the same genus.  The female will die shortly after laying her eggs.  She does not feed as an adult as she has no functioning mouthparts.  The caterpillars may hatch as soon as a week and they can be fed the leaves of oaks.

Letter 5 – California Oak Moth

Subject: Brown Moth Attack!
Location: San Francisco Bay Area
October 14, 2013 6:55 pm
Hello Bugman,
Lately, my school and my house have been infested with these interesting small brown moths. They are around two centimeters wide resting and have feathery antennae. I have looked on the internet and can’t figure out what they are! There are thousands of them all over the oak trees. Please help me solve this mystery!
Signature: Sidney

Hi Sidney,
Thank you for including the information about the oak trees, as that helped us to quickly locate the identity of the California Oak Moth, Phryganidia californica, by matching to this photo on BugGuide.  Only the males have the feathery antennae.  According to BugGuide, there are:  “Two generations per year in northern California; sometimes a third generation in southern California. Overwinters as a larva on underside of oak leaf. Populations are cyclic: larvae are common in some years, and virtually absent in others.”  The caterpillar is known as the California Oakworm, and according to the UC Davis Integrated Pest Management System:  “The California oakworm (Phryganidia californica, family Dioptidae) is one of many species of caterpillars that feeds on oaks. It is the most important oak-feeding caterpillar throughout its range, which extends along the coast and through the coastal mountains of California. Damage is most common on coast live oak (Quercus agrifolia) in the San Francisco Bay and Monterey Bay regions. Populations vary unpredictably year to year from very high to undetectably low. Healthy oaks generally tolerate extensive loss of leaves (defoliation) without serious harm, so treatment to control oakworms usually is not recommended.”  This must be one of those plentiful years.

Thank you so much!! 🙂
Sidneh

Letter 6 – Oakworm Moth and subsequent tragedy

big brownish-reddish moth
April 9, 2010
HELP! I have 15 of these big, ugly brownish-reddish colored moth looking flying insects swarming my front porch!! Three of them are dead, which makes me happy. They’re fuzzy. I’m not very good with adjectives! I can’t even leave my house right now!!!! Please, please PLEASE help me!!!!
with a pen?
Slidell, LA

Dear with a pen?
With a keyboard might be more appropriate since this is an electronic communication, and there is no ink.  This is an Oakworm Moth in the genus Anisota.  BugGuide lists at least three species that range in Louisiana.

Ed. Note:
We got the following response, which saddened us to the point we could not even respond any further.  The intolerance and arrogance some people feel toward the natural world positively appalls us.

Ahhh, but you can not sign something on a computer, so why ask? =) Maybe it should have said “What name would you like to be called?” =) And to prove that I am, in fact, a human, it asked what color is grass. I typed brown because I haven’t seen green grass in quite awhile. Thank you very much for answering my question! Do they normally swarm like that? That was INSANE! 3 of the stupid things died after flying into the windows enough times. The rest took ant and roach killer and a big foot. Now we need a pressure washer to get the yellow guts off of the concrete. Thank you, thank you, THANK YOU so much for answering my question! I wasn’t sure y’all would answer since it wasn’t any sort of exotic bug =)  -Jennifer

Letter 7 – Mating Oakworm Moths

Moth Mates
Hello,
I saw a bunch of these bright moths swarming the garage at work. This picture was taken in July. These guys were hanging from a roof. I imagine the little one is the male? Thanks,
Katie
Benton Harbor, MI

Hi Katie,
These are mating Oakworm Moths in the genus Anisota. The World’s Largest Saturniidae Site lists three members of the genus in Michigan and they can be difficult to tell apart. We believe these are either Anisota senatoria, the Orange-Tipped Oakworm Moth or Anisota virginiensis, the Pink-Striped Oakworm Moth. More information on this genus can be located on BugGuide. Yes, the smaller darker moth is the male.

Letter 8 – Bug of the Month October 2016: Oslar’s Oakworm

Subject: Orange Caterpillar with Black Spikes
Location: Canyon de Chelly National Monument, Chinle, North Eastern AZ
September 30, 2016 11:09 am
Hello, I’m trying to identify this caterpillar (see photo) that we encountered at Canyon de Chelly. I have found some pictures of similar ones but nothing that looks exactly the same. Can you help?
Signature: Jeannette

Dear Jeannette,
This is one of the Spiny Oakworms in the genus Anisota, and because of your Arizona location, we are relatively certain it is Oslar’s Oakworm, Anisota oslari, which is pictured on BugGuide.  According to BugGuide:  “Larva – last instars are brick red” and “Larvae are known to feed on oaks, including Mexican blue oak (Quercus oblongifolia), scrub oak (Q. turbinella), and Emory oak (Q. emoryi).”  There are several related species in the genus found in eastern North America as well, and we frequently get images of mating Oakworm Moths  and newly emerged Oakworm Moths submitted to our site.  Since it is the first of the month, we are tagging your submission as our Bug of the Month for October 2016.

Thanks so much – it’s a beautiful caterpillar and I was frustrated trying to find out what it was. Your site is great!
Jeannette

Letter 9 – Freshly Eclosed Oakworm Moth

Subject: What is this bug ???
Location: South Carolina
May 25, 2014 6:52 pm
No clue as to what this bug is. Picture taken by a friend in South Carolina today.
Signature: Suzee

Dear Suzee,
We just realized that the last four postings we made today are all moths.  This is a freshly eclosed Oakworm Moth in the genus Anisota, and its wings have not yet fully expanded after emergence from the pupal stage.

Letter 10 – Freshly Eclosed Oakworm Moth

Subject: What is this?
Location: Venice, FL
June 24, 2014 7:46 am
Wondering if someone knows what this is. It’s about as long as your pinky finger
Signature: Thanks, Suzanne

Dear Suzanne,
We have just returned from the office after a ten day hiatus and we have hundreds of unanswered identification requests.  We think the only way to approach this tremendous backlog is to choose one letter per day from our absence and try to catch up to the best of our ability.  Your letter is the first we are responding to.  This is a freshly eclosed Oakworm Moth from the genus Anisota, and its wings have not yet reached the fully functional size, which often takes several hours.  Before the wings expand, many moths resemble caterpillars.  Here is a photo from BugGuide for comparison.

Why —- THANKS!

Letter 11 – How to increase the life span of an Oakworm Moth

Subject: anisota virginiensis
Location: winter park, fl
March 3, 2017 10:55 pm
Is there any way to keep an adult one alive? I know they cannot feed, but as silly as it sounds..I’ve grown accustomed to one near my apartment and even walks on my hand..is there any way to have it survive longer than expected?
Signature: ?

Oakworm Moths in the genus Anisota, like other members of the family Saturniidae, do not feed as adults, and if they do not mate and reproduce, they will not contribute to the gene pool for the species.  So, Oakworm Moths as well as other Giant Silk Moths will either die of old age, fall prey to a predator, or meet some accidental end.  Since the individual you are inquiring about is resting near your home, it should be protected against predators or accidents, and hopefully it will mate and reproduce.  A sheltered location is one means of extending the life as long as possible, though after a week, your individual should be considered quite old for its species.

thank you so much for getting back to me. it didn’t live passed a week, but it’s good to be informed. I appreciate the time you took to respond.

Letter 12 – Japanese Oak Silkmoth

Japanese bugs
Hi – I’m happy to have found your site – I have a new site to waste time with! I live in Japan and there are tons of bugs that I’ve never seen before. I think I’ll add some neat pics to your collection as well. I haven’t been able to find any information on these insects – almost all the information i find is in Japanese, and I’m not quite proficient in the language to learn interesting things about these guys. All of these pictures are from Shikoku (the smallest of the 4 main islands in Japan) Any information would be appreciated, I haven’t seen any info on your site about any of these, so maybe you’ll have some fun researching these..
Nick
This is a huge moth we found on the wall. It was about the size of a small bat. It flies like one too. I’m wondering if that’s how it camoflauges itself from birds. The size is about 3.5 inches from from head to tail. The wingspan is impressive.

Hi Nick,
It didn’t take us too long to identify your Japanese Oak Silkmoth, Antheraea yamamai. It is a highly variable species, with wings that vary from brown, through yellow, through orange. We found a website with wonderful images of the variations.

Letter 13 – Mating Oakworm Moths

Mating Moths
I’ve attached a photo of two moths who were mating at high noon in the middle of the street last summer. I live in Gainesville, Florida, and haven’t been able to identify them. Would you be able to help me ID them, and determine which is the male and female? P.S. I think this would make a nice addition to your Bug Love gallery. Thanks,
Krista

Hi Krista,
These are Oakworm Moths in the genus Anisota. There are several species that closely resemble one another, and we don’t feel comfortable trying to identify the exact species. The smaller moth is the male.

Letter 14 – Mating Oakworm Moths

mating Anisota moths
Location: Fayetteville, NC
May 27, 2011 7:31 am
Found these yesterday on a stump that was also home to some new bird hatchlings. I couldn’t get a dorsal view without disturbing them, but even from the underside, they’re very pretty. Hopefully they finished their business before the mother bird looked up.
Signature: Patrick

Dear Patrick,
Thank you so much for sending in your photo of mating Oakworm Moths in the genus Anisota.

Letter 15 – Mating Oakworm Moths

Subject:  Two lovebirds
Geographic location of the bug:  Waleska Georgia
Date: 06/19/2019
Time: 04:50 PM EDT
Your letter to the bugman:  Saw these two on back of my home. They have bright orange body with bold magenta wings with white spots.
How you want your letter signed:  Cyndi

Dear Cyndi,
These are mating Oakworm Moths in the genus Anisota, and there are several similar looking species in the genus, and based on BugGuide data, at least four species are known from Georgia.

Letter 16 – Mating Pink Striped Oakworm Moths

Moths breeding
Location:  Dallas Fort Worth Texas
July 18, 2010 2:40 pm
These moths were breeding on a piece of wood on my driveway. Date was April 21, 2010. Dallas, Fort Worth area of Texas.
Sarah Goodrich

Hi Sarah,
Your moths are Oakworm Moths in the genus Anisota, most probably the Pink Striped Oakworm Moths, Anisota virginiensis, though there are other members in the genus that look quite similar.

Letter 17 – Mating Pink Striped Oakworm Moths

Subject:  Oak Eggar?
Geographic location of the bug:  North Carolina
Date: 06/30/2021
Time: 07:28 PM EDT
Your letter to the bugman :  This loving couple was found in Charlotte, NC. They look like oak eggar moths, but those live in the UK. Are they oak eggars or something else?
How you want your letter signed:  Jeremy in Charlotte

Dear Jeremy,
The European Oak Eggar is in the family Lasiocampidae and according to UK Moths:  “The Oak Eggar, despite its name, does not feed on Oak, but is so-called because the shape of its cocoon is acorn-like. ”  You have an image of mating Pink Striped Oakworm Moths, Anisota virginiensis, which are pictured on BugGuide.  If our archives are any indication, sightings of mating Pink Striped Oakworm Moths are not uncommon.

Letter 18 – Newly emerged Oakworm Moth

Subject: Emerging moth
Location: Fort Myers, Florida
March 12, 2014 6:40 pm
Found this moth with wrinkled wings in my garden today, March 12, 2014. It is on the ground on mulch and amongst fallen leaves of a live oak . I live next to a wetland preserve of pine, cypress, and wax myrtle. Is it a newly emerged Imperial Moth? If so, how long does it take for the wings to fill out and the moth to fly away? It has been there about 10 hours. The body of this moth is huge! About 2.5 inches long – and fat as my index finger. Thought I would bring it into the screen porch to keep it safe from predators, but when I approached it with a piece of paper, it expelled a shot of liquid from its anus; so figured it was best to leave it alone!
Signature: Liz

Hi Liz,
We believe this is one of the Oakworm Moths in the genus Anisota, and this photo of a newly emerged Pink Striped Oakworm Moth from BugGuide shows many similarities.  Adult Oakworm moths do not eat and they only live a few days, long enough to mate and lay eggs. 

Hi Daniel,
Thank you, looks like the moth that was there.  There was another one like the other moth in your photo, that seemed to be trying to mate with the one on the ground.
And the one I photographed appeared to be trying to lay eggs.  However, I will never know since she has disappeared from the garden overnight.  Thanks again, Liz

Letter 19 – Oak Eggar Caterpillars from Cyprus

Subject: caterpillar
Location: Cyprus mediterranean ocean
November 18, 2012 2:44 am
i owned 4 of these before all the way to moth stage and i know they’re some kind of southern or western tent caterpillar, the moths are almost exactly the same but i just cant find anything on the internet that looks exactly like it
Signature: tatiana h

Hi Tatiana,
By taking a circuitous route, we believe we have identified this caterpillar as an Oak Eggar Caterpillar, Lasiocampa quercus.  We started with the Insects of Cyprus website and found this photo of a moth and then searched its scientific name until we found this image of the caterpillar on a French website that looks identical to your individual.  More photos can be found on the Moths and Butterflies of Europe and North Africa website and more photos and information are available on the UK Mothswebsite which states:  “The larvae change considerably in appearance during development, and care should be taken not to confuse early instars with the larvae of other eggars (Trichiura, Eriogaster and Lasiocampa species). Fox moth (Macrothylacia rubi) and the Drinker (Euthrix potatoria) should be checked when identifying last instar larvae. Early instar larvae from moorlands are often duller, especially on the dorsum, than larvae from other habitats.”  We suspect there is much local variability in the coloration and markings of the caterpillars.  

Letter 20 – Oakworm Moth

What is this moth?
Hey, bug folks. There are several of these red guys hanging around lethargically on my front stoop. Never seen this type before! Any ideas? Thanks,
–Andy

Hi Andy,
This is one of the Oakworm Moths in the genus Anisota. There are several species and we have a problem distinguishing one from the other.

Letter 21 – Oakworm Moth

what’s THIS bug?
Other than a moth — that much I know. Took this picture in the summer in northeastern North Carolina.
THANKS!
Tommi

Hi Tommi,
This is an Oakworm Moth in the genus Anisota. There are several similar looking species.

Letter 22 – Oakworm Moth

Subject: A type of polyphemus moth?
Location: Canton, GA
July 12, 2014 4:25 pm
Hi, can you help identify this moth. A small swarm came to my deck this afternoon, only one is still here. North Georgia, wooded area. There is also a large white spot on the lower wing (white spot, on the purple wing if opened).
Signature: Christine

Hi Christine,
This is an Oakworm Moth in the genus Anisota, and it our opinion, it looks like the Pink Striped Oakworm Moth, Anisota virginiensis, that is pictured on BugGuide.  Oakworm Moths and the Polyphemus Moth are in the same family, Saturniidae.

Letter 23 – Oakworms Mating

more bug love
Thought I would send this pic of spiny oakworm moth love! Your website is great, and I just wanted to contribue.
Michelle in Florida

Hi Michelle,
This is definitely an Oakworm in the genus Anisota, but we can’t conclusively identify the species. Thanks for the image.

Letter 24 – Orange Striped Oak Moth

moth?
Hello WTB,
WHat a great website! My daughter and I spent a lot of time on the internet trying to identify this moth that we found but could not find it anywhere? Do you know what this is?

This is an Orange Striped Oak Moth, Anisota senatoria. Adults can get very plentiful at times.

Letter 25 – Orange Striped Oak Moth

Orange Striped Oak Moth
Hey bugman, A few weeks ago, I e-mailed you about some moths that were all over my building at work in Riverhead, NY. Our tree company identified them for us, but you do not have a picture of them on your website. Here is a picture of the Orange Striped Oak Moth. Maybe you can put it on your site for others to see. Thanks for your time.
Mike D

Hi Mike,
Thanks for the letter and photo. We also located a link that talks about how this moth appears in great numbers. The Orange Striped Oak Moth, Anisota senatoria, is a close relative of the Virginian which we do have images of.

Letter 26 – Orange Striped Oakworm

Some bug pics for you to enjoy
Hi Bugman,
I have a new hobby. Ever since I found your website (it was in an Earthlink newsletter I received) I have felt the need to identify all unknown bugs that cross my path. I also inform all witnesses of said bugs as to what kind of creature they witnessed. This is a rather peculiar hobby for me because I despise bugs, as they give me the heebie jeebies. My new hobby, however, has given me a new-found respect for these creatures. Since coming to your website, I have been able to identify a house centipede, the millipedes that were invading my home, a wolf spider (HEART ATTACK!) the orange striped oakworms that are busy, busy, busy in my driveway and the golden orb spider who has spun her web by my mailbox. I think you will be happy to know that, this time, instead of pointing and turning my head so my husband could squash them, I have mustered up the courage to take some pictures. They were taken outside of my home (thank God they were outside) in Matthews, NC (Charlotte area.) One is of an Orange Striped Oakworm and the other is a Golden Orb Spider. Please enjoy.
Thank you for your informative and fun website.
Sincerely,
Kathy Richardson

Hi Kathy,
Your letter gives us such a warm feeling. We are thrilled that you are embracing photography as we are both photography instructors. We are also very happy that you now respect the Arthropods that you are encountering. We have decided to post your Orange Striped Oakworm, Anisota senatoria instead of the Golden Orb Weaver as we have many photos of that impressive spider.

Letter 27 – Orange Striped Oakworms

Orange-Striped Oakworns enjoying some sand
Location:  Swanton, OH
August 29, 2010 12:43 pm
Went to the Sand Dunes today – Oakworms everywhere! They had decimated many of the baby oaktrees in the area, but my favorite part was the little tiny trails COVERING the sand.
Katy

Hi Katy,
Thanks for sending us your photos of Orange Striped Oakworms.  They must be very plentiful if trees are being defoliated.  The perspective of the trail photograph is a nice addition.

Letter 28 – Oslar’s Oakworm

Subject: orange caterpillar
Location: Flux canyon, Arizona
January 14, 2014 9:34 am
Hi….
I’ve scrolled around the internet a lot and so far have not found a pic of this caterpillar.
It was crawling around high grasses in Flux Canyon, southern Arizona….near the town of Patagonia.
I saw it in October…..
Signature: Susan Warner

Hi Susan,
We quickly identified this Caterpillar’s family as the Giant Silkworms, Saturniidae, and once we established that, identifying this striking caterpillar as Oslar’s Oakworm, Anisota oslari, on BugGuide did not take long.  According to BugGuide:  “Larva – last instars are brick red” and “Larvae are known to feed on oaks, including Mexican blue oak (Quercus oblongifolia), scrub oak (Q. turbinella), and Emory oak (Q. emoryi) .”  There are several species in the genus in the eastern US including the Orange Striped Oakworm. 

Letter 29 – Pink Striped Oakworm

Unknown Caterpillar
What is this little guy? I live in Melbourne, FL and we found him on our back wall. He is about 2 inches long. Any ideas?
Thanks.
Cindy J.

Hi Cindy,
This is a Pink Striped Oakworm, Anisota virginiensis. Here is a USGS link with additional information.

Letter 30 – Pink Striped Oakworm

Jones Family catapillar picture
Hello we are the Jones Family from Orlando Florida, and we were happy to run across your website, while trying to identify this creature. The closest we came was the orange striped oak worm picture on your website, but obviously ours had different coloring. After we took some pictures we let him/her go on its way. Our family particularly my seven year old son have started a small butterfly garden in which we hope to continue to build on, we will definitely continue to send more pictures in the future. Do you think you can tell us what this is a picture of and maybe a little about this creature such as what it turns into. Thanks
The Jones Family Arlene, Craig, Sean, Aaron, and Caleb

Hi Joneses,
Your caterpillar is a Pink Striped Oakworm, Anisota virginiensis, and it is a close relative of the Orange Striped Oakworm. It will metamorphose into a small Saturnid Moth.

Letter 31 – Pink Striped Oakworm

Subject: Caterpillar
Location: Coconut Creek
December 15, 2016 4:49 pm
I was wondering if you identify this caterpillar for me
Signature: Normal

Dear Normal,
This is one of the Oakworms in the genus Anisota, and we believe based on this BugGuide image that it is a Pink Striped Oakworm, Anisota virginiensis.

Letter 32 – Pink Striped Oakworm

Subject:  Is this a green striped maple worm?
Geographic location of the bug:  Central Florida
Date: 11/13/2017
Time: 07:12 AM EDT
Hi! I was trying to identify this caterpillar and the closest thing I’ve been able to find so far is a rosy maple moth caterpillar. The structure of the caterpillar in question looks right but the color doesn’t quite match what I’m finding online. How much color variation is there in a caterpillar species? Thanks in advance for your attention. I love you guys!
How you want your letter signed:  Jenn

Dear Jenn,
Your caterpillar looks similar to the caterpillar of the Rosy Maple Moth, which is pictured on BugGuide, however, your individual is a different species in the same Royal Moth subfamily Ceratocampinae.  Your individual is a Pink Striped Oakworm, Anisota virginiensis, a species with three distinct subspecies, that is pictured on BugGuide.

Letter 33 – Pink Striped Oakworm Moth

Subject: Bug thats wings expanded fast
Location: Florida
September 23, 2016 2:03 pm
I was outside and i found this little orange bug that looked kinda cute and it had red ears but after a little while it hung on to a leaf for a few minutes and all of a sudden the ears turned into wings! Do you know what bug this is?
Signature: Alyssa

Dear Alyssa,
This looks to us like a freshly eclosed Pink Striped Oakworm Moth, Anisota virginiensis, or another member of the genus Anisota.  You can compare your image to this BugGuide image.  Here is an image of what you described you first saw when you originally noticed this individual.

Letter 34 – Pink Striped Oakworm Moth

Subject:  Red moth
Geographic location of the bug:  Conyers Georgia
Date: 09/24/2021
Your letter to the bugman:  What kind of moth is this
How you want your letter signed:  J Lowry

Dear J Lowry,
This is an Oakworm Moth in the genus Anisota, probably the Pink Striped Oakworm Moth, Anisota virginiensis, which is pictured on BugGuide.

Letter 35 – Pink Striped Oakworm Moths Mating

Pink Striped Oakworm Moths “Bug Love”
Species: Anisota virginiensis
Location: Gainesville State College, Oakwood, Hall County, GA, USA
Date/Time: 8 JUL 2008/1210 hrs
The last things I expected to see after my math test were these lovely pink striped oakworm moths “in flagrante delicto” about five feet up a large tree-trunk. According to www.butterfliesandmoths.org , they usually mate in the morning, but I guess these guys were late risers (or long maters!). Unfortunately, I didn’t have my digital camera with me at the time, so a friend took the picture on his phone. With the reduced image quality, the almost impossible fuzziness of the moths is lost, as well as the amazing luster of their colors. The male’s body was not dark brown, as the aforementioned site suggests, but was instead a deep red-purple and orange. Finding these moths made my day, test and all!
Jon-Jacob Deal
Photo by Brian Edgar

Hi Jon-Jacob and Edgar,
Thanks for sending us this romantic image of mating Pink Striped Oakworm Moths.

Letter 36 – Oslar’s Oakworm

Mystery caterpillar
Hi there- I was doing some field work in Nogales, Arizona (Santa Cruz County) and came across this caterpillar. There was a large group of them scattered among 3-4 oak trees. I unfortunately know little about insects, and was not having much luck identifying the species by comparing my pictures to ones on-line. I was hoping that you could help me identify these critters. They were an orangey-red color with black protuberances. I did not see them in any other tree besides the oaks and when they weren’t eating the leaves, they were bobbing from side to side. Thanks.
Joanna Cezniak

Hi Joanna,
This looks like a Spiny Oakworm in the genus Anisota.

Ed. Note: (11/21/2005) The following correction just came in from Jim Tuttle.
I enjoy scrolling through your website periodically, and from a practical point of view I am always looking for interesting records, food plants, and range extensions for the Sphingidae, although I always take notes of the Saturniidae too. Good job, it is a useful tool for the nature lover or the frantic gardener. I casually noted two id’s that need correcting. Spiny Oakworm 10/18/2005 is actually Anisota oslari. Keep up the good work!!
Regards,
Jim Tuttle

Letter 37 – Oslar’s Oakworm

Oak eating caterpillar
Hi there, I love your site. We recently found this guy munching on a scrub oak near Santa Fe, NM. We found several more on an oak tree in our back yard the next day. They all seem to have moved on or pupated by now but I would love to know what species they are.
Thanks,
Jeff Sherman

Hi Jeff,
This is a Spiny Oakworm, Anisota stigma. Our old Holland Book lists them west to Missouri, but the range might have expanded or the information at the time of publication may have been incorrect.

Correction:  January 14, 2014
Based on a new identification today, we now know that this is Oslar’s Oakworm, Anisota oslari, a different species in the same genus.

Letter 38 – Spiny Oakworm Moth

moth
One day in June (in North Carolina), this moth got trapped inside our tent and later we were swarmed by others trying to get to it. Can you tell us what it is? Thanks!
P.S. Love your site!

Moths in the genus Anisota are known as Spiny Oakworm Moths. Both males and females are reported to release pheromones and frenzied mating orgies follow. Guess you witnessed one. BugGuide is attempting to sort out the genus.

Letter 39 – Spiny Oakworm Moth Caterpillar

Subject: Orange caterpillar with gray stripes and black horns
Location: Winterville, GA
August 16, 2015 8:48 pm
This was enjoying a leaf on an oak sapling in my woodland garden in the yard this afternoon, August 16th. I hope it’s something native because I left it to eat.
Signature: Stephanie

Dear Stephanie,
This is one of the native Oakworms in the genus Anisota, and we believe the closest match we can find on BugGuide is the Spiny Oakworm Moth Caterpillar, Anisota stigma.  According to BugGuide, the caterpillars feed on the leaves of:  “Oak; also reported from hazel and basswood.”  Your individual appears to be on a willow leaf.  Can you please provide the name of the tree the caterpillar was feeding upon as it does not look like an oak to us. 

Dear Daniel, That is VERY Interesting. Thank you for getting back to me! Ok, the oak tree is a youngster, a little sapling so it’s tough for me to tell but I would say it is in the red oak family…do oaks every hybridize? Don’t they sometimes…it’s hard to tell because it’s young but if I had to guess I’d say maybe a Trukey Oak or a Southern Red oak…or maybe even a hybrid with a water oak or maybe a Laurel oak. I am just very skeptical about it being a willow because I have to acres, and this little woodland section of the yard is what I wouldn’t hesitate to call “dry woods.” I have no bodies of water on my property and all the other things that have sprung up naturally out there (Amer Beauty Berry, White oaks, Willow Oak, Hickory, Serviceberry, Mulberry) are things associated with dry woods I think. I could take some better pictures of the tree tomorrow (and maybe even the caterpillar–she was still there today, and bigger) assuming she’s still out there, if you think that would help. I also live in the part of GA where we have Oglethorpe oaks, for whatever that’s worth.
Thanks for getting back to me!
Stephanie

You do not need to send us images of the tree Stephanie.  You have confirmed that there are plenty of oaks in the vicinity.

Letter 40 – Virginia Oakworm

Two moths…
Hi!
Great site! My parents and I found a couple of interesting moths. I was hoping you could identify them for us. (Both were seen in Massachusetts…) My moth was about 1.5 – 2 inches long, top to tip. The body was fuzzy and BRIGHT ORANGE. Not very good for hiding in New England woodlands, I’m afraid… (Especially not on the side of a red house!) My parents’ was about twice that size. The body was also fuzzy, but more of a beige… Sorry for the blurry pic, but he was camera-shy… Regards / Met vriendelijke groet / Mit freundlichen Grüssen,
Amanda Ellsworth

Hi Amanda,
Your moth is the Virginia Oakworm, Anisota virginiensis, or a closely related species in the same genus. Your parents photographed a Polyphemus Moth. Both are Giant Silk Moths or Saturnid Moths.