What a Woolly Worm Knows

Woolly Bear


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It’s time again to shine the spotlight on a certain caterpillar—the woolly worm! According to folklore, this fuzzy fellow has the ability to predict the weather.

Also called the woolly bear caterpillar, the banded woolly bear, or just woolly worm, he’s the larva of the Isabella tiger moth (Pyrrharctia isabella).

In terms of appearance, the caterpillar has segments of either rusty brown or black.  Often, he is black with more rust segments in the middle, although he might be almost all black or all rust.

Folklore says that if the rusty brown band is wide (more segments), then it will be a mild winter. The more black there is, the more severe the winter. 

Note that white or yellow or other colors of fuzzy caterpillars are NOT the same type of woolly worm.  We’ll leave the weather-prognosticating “skills” to your own observation!

For more woolly worm fun, check out the Woolly Worm Festival in Banner Elk, North Carolina. At this annual mid-October event, woolly worms race up to the top of their 3-foot-long strings, accompanied by thousands of cheers. The bands of the winner predict the coming winter.

Have you seen a woolly worm in your area? What did it look like? Feel free to share your experience.

Read more about woolly worm weather lore.

~ By  Heidi Stonehill

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black wooly in February 2017

I found an all black wooly in my driveway this morning. It is February in Massachusetts. It has been below 40 here this past week or so. this morning only 22 degrees. what does this mean?

Found a Woolly Worm

Found one January 31st on the sidewalk outside. Is this typical?

woolly worm

In Minnesota!

one special woolly worm

Thank goodness that worm has a wool coat to help keep it warm! Just kidding. Actually, it is probably uncommon to see an active woolly worm in winter in your area, unless perhaps you’ve had a span of unusually warm temperatures. Over winter in cold climates, the caterpillars hibernate in sheltered areas, such as in leaves or under logs. The larvae have a chemical that keeps the interior of vital cells from freezing; the rest of the body, however, does freeze solid. When the weather warms, the caterpillar thaws out, then spins a cocoon and eventually emerges as a moth.

Saw my 1st Woolly Worm 3

Saw my 1st Woolly Worm 3 weeks ago-- All Black so in Kansas City, KS I'm expecting a Hard Winter-- Yes I believe in the Prediction!!!

I saw something about 4 in

I saw something about 4 in long and solid black inside my ground floor condo today. SCARED me to death. HOPE it was a catipillar vs about any other kind of creature. THE critter is still at large....

FROM Atlanta

OMG! Did you call 911? LOL!

OMG! Did you call 911? LOL! Is it still lurking around your home? Would love to see a picture of it. If you see it again, throw a bowl over it, slide something underneath and walk that monster to the door as fast as you can! ;) Good luck.

Wooly Caterpillar

Looked and looked but couldn't find any. Finally, one was crawling on the driveway today. Only Jan, Mar, Apr and Oct were black. All the rest of the caterpillar was golden brown. YEAH


Only recently [past couple weeks] have I seen any of these and most have been dead; one was lethargic. We are experiencing a lengthy dry spell and perhaps this is affecting them. Most have been black; one had a small band of brown in the middle; and I saw one cream color .... all but the lethargic black one was dead. A friend said a friend of hers [Virginia, Pennsylvania areas] commented there was so many they were all over the roads.

Wooly worm

Saw one this fall..was almost all reddish with tad of dark on each end. Oakbrook il

Woolly Bear Caterpillars

In the past week,I have seen one that was nearly all brown and one that was nearly all black. Now what!

differing woolly worms

It sounds like those two caterpillars are having a difference of opinion over their predictions for upcoming winter! Actually though, folklore aside, scientists have found that the color is affected by several factors, including the age of the caterpillar and the environmental conditions of the past winter. For more information, you might be interested in this page:

Woolly Worm Wake Forest NC

I found a solid Black Woolly Worm today after work.

FredVegas, VA sighting

Saw 3 this past weekend -- 2 in So. MD (both totally black) and 1 in VA (mostly black, w/tinge of rust). We've been having increasingly harsher winters in NOVA the past 4-5 yrs. We'll see if these 3 prognosticators were close nuff for that cigar.

psychotic woolly bears

I'm in eastern PA. I've seen several with very wide rust bands and several that are completely black. They're the politicians of the caterpillar world, evidently.

Wooly Bears

I'm a bit frightened to say this, but I have seen several that are solid black!!

Wooly bears

Me too! That is what brought me to this article.

Woolly worm

My grandparents always told me that all colors mean something. For instance, if the front was black winter would start off bad, middle brown mild, last part black bad. Or the opposite if colors are reversed. With that being said, I have seen two so far one was all black and the other one was mostly brown in the middle. So I'm not sure.
French Creek, WV

wooly worms

Why havent I seen any wooly worms at all this fall?

Woolly Worms

I've seen two and they have been pure black with no brown at all. :(

All Black in SE PA

I saw one woolly bear about a month ago, back in September. It was short and solid black. Hoping that means lots of snow for skiing! My husband is a teacher so we love snow days!

Wooly Caterpillar

All rust, not a hint of black. From Eagleville, TN.

Woolly Catapillar

This weekend during our daily walk several displays of very small fuzzy woolly's were crawling on the street doing a rust color coat. No stripes, no black, just rust. This is in the Central Pennsylvania region near the capitol. Looks like a mild winter here!! (based on Almanac data)

Woolly Worm

Just came across a Woolly Worm with a wide brown band in Franklin, TN. He was so cute and fuzzy. Looking forward to learning more about them.

Wooly Bear sightings

My daughter just came over to me & told me she just saw an all black wooly bear in our backyard in Townsend, DE. Oh boy... can't wait to see if it's going to be a rough winter!! She is very excited!!!

Wooly worm

we just saw our first wooly on our back porch,we live on a farm in mid mo.and he was very fat and black as night from end to end,bet we have a heavy winter.Sept.10,2016

wooly bear caterpillar

The caterpillars here in Yelm have wide spaces between the black. Here's hoping for a mild winter.

Seeing a woolly worm

I saw my first woolly a couple days ago. It was all black. They are really cute little creatures. I enjoyed reading about them.

Found one in my laundry room

Found one in my laundry room scared the crap out of me!!!!! Scooped it in a cup as soon as I seen it. I didn't know if it would hurt my son who is a year and a half

Red and Black Wolly Worm Caterpillar

I first saw him in the back yard last week and again today, the first day of spring. We had a mild winter and it is looking for a place to make a cocoon, I think.

wooly bear caterillar

i got a wooly bear caterpillar in my jar now and it is all black what that mean

southern Wisconsin

Saw one yesterday at Horicon Marsh in southern Wisconsin with a large brown band in the middle. It was very determinedly heading west. Folklore in my home state of Missouri says that a woolly bear moving south means a rough winter. I have no idea what heading west might mean other than he knew he could find a rock in that direction.

Southern wisconsin here also.

Southern wisconsin here also. Same coloring as the one spotted near Horicon marsh. Wide rust band in the middle. Not sure which direction THIS one was headed, tho. He was curled in a defensive little ball. :)

Wooly Bear Worms

I saw one today he was all BLACK, so far my State has missed several years of bad weather. So the winter of 2015/2016 must be going to be severe. Time to stock up on supplies.

Woolley bear

Saw a woolly bear tonight around 7:30 pm on the floor of our horse barn. First one this year.Laying out flat it was all black and the bristles seemed extremely long from others I've seen. When it curled into a ball I could faintly see rust color in the middle of the body. We are about 30 miles SW of Lansing MI

Just found a woolly

Just found a woolly caterpillar. Its black bands were close together. There wasn't as much orange as usual. Black bands were wide. Kinda early to see them. Found this guy in the yard. NW michigan across from Green Bay.

1/7/15 Cumming GA We have

1/7/15 Cumming GA We have lived in the same home for 7 years and I have never seen one, ours is solid black. The weather has fluctuated and our new outdoor pet travels (very slowly) around sidewalk apx. 5 ft from the front door and the landscaping there. It has been enjoyable to see if and where he is as we go in and out!

3/4/14 I live in NW Indiana

3/4/14 I live in NW Indiana where spring has not begun yet. We had a snow storm Sunday, and near zero temperatures overnight. I saw a "Wooly" today on my patio!!! A sign of Spring, I hope!!

I saw a woolly bear today

I saw a woolly bear today 1/26/14. The center rust/brown band was at least 1/2 the length of the caterpillar with only very narrow black end bands. I sure hope that's predicting an early spring.

I just saw a Wooly Bear today

I just saw a Wooly Bear today on 1/14/2014 in Louisville, KY



I just took a photo of a

I just took a photo of a wooly bear in Morristown, NJ. Dec. 4, 2013. The rust band equals one third of the length of the catepillar.

..i just held one and put it

..i just held one and put it on a leafy bush..there's been a good amount of them around here..just discovered here what they were called.. i live in the hudson valley area in new york..most of them have been half and half with the rust and black..some more or less with one color or another..but i didn't know about the coloring meaning something..so i'll keep better track of what i find from now on..i find if you pick one up and it curls into a ball..blowing very very gently on it..makes it come out of the ball and start walking again..i always put them on a leafy bush..they like it and crawl inside the branches..

I live on the South Shore of

I live on the South Shore of Nova Scotia, and they seem to be out and about everywhere.

Got some nice photos yesterday, and the bands were wide, thus I expect a mild winter :) Yeah! Yay!

Will gladly share my photos, just not sure where :)

Wooly bear here in Central

Wooly bear here in Central Minnesota has a small rusty colored band around its middle.

I live in western central OH

I live in western central OH and I've seen many woolly bears and everyone of them are totally black.

I saw one a couple of weeks

I saw one a couple of weeks ago and it had a big brown band! I'm ready for another mild winter. I live in central Michigan.

Far north central Wisconsin,

Far north central Wisconsin, the only wooly bear I saw was all black. They have been rare up here in the last 5 years. Because of drought?

I live in PA and the wooly

I live in PA and the wooly bears have a small black band in front and back the middle is brown and larger than the black ....MILD winter? I always have faith in them. I am 72 years old so I know these wooly creatures a long time.

I live in Western West

I live in Western West Virginia and every wooly worm I've seen are completely black.

I'm from delmar on the

I'm from delmar on the eastern shore of maryland, and the most I have seen have been mostly rust with little black and white ones.

Here on Eastern Shore of

Here on Eastern Shore of Maryland we are loaded with them! For what it's worth, right now they are mostly rust colored. It's been quite warm, no frost yet.

I saw one a few weeks ago in

I saw one a few weeks ago in North Alabama and it was solid black.

I saw one a few weeks ago in

I saw one a few weeks ago in n.Alabama and it was all black.

I have seen a few Woolly

I have seen a few Woolly Bears in the last week or so here in the Shenandoah Valley. They all were just about black.

I did NOT see many wooly

I did NOT see many wooly worms this year....why? The one I did see showed me his orange band.....and he did not have a very black, thick coat...!

the only 1 ive seen so far

the only 1 ive seen so far this year was solid white

The first woolly bear I've

The first woolly bear I've seen so far in south east Kentucky had unequal black bands, the back was smaller.

I have not seen many woolly

I have not seen many woolly bears this year and saw only 8-9 butterflies all summer.

I saw a wooly bear a few days

I saw a wooly bear a few days ago and it had two black stripes and one rust stripe that seemed to be divided almost equally in thirds.

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