What is this devil?

[BlueBee]

Anybody know what this little devil is?  He's on a sumac bush.

[mikecva]

No idea, but from the leaf it is eating and the leaf stub behind it, I would say it is very distructive. You might send a picture of it to you local Ag dept and ask them.   -Mike

[Scadsobees]

That's the horniest caterpillar I've ever seen!

www.bugguide.net

Spend some time on there and you'll find most anything in the insect world! :-D

[yockey5]

I have seen them but I do not know what they are.

[boca]

Believe it is a young caterpillar of the regal moth called hickory horned devil.
Later it becomes colourful.

[Francus]

A quick check on Wikipedia and it seems you may be correct! The color is off, but that may be due to the age of the catapillar.

http://en.wikipedia.org/wiki/Hickory_Horned_Devil

[Riggs]

Bait at the nearest fishing hole.... :)

[Scadsobees]

Forget the fishing hole!  My kids love to keep them in containers and feed them till they're cocoons, then watch them hatch out!  Looks like an ample food source right there....

It is really fun to watch... my 7 yr old raised several monarchs from when they were about the size of two periods ..  He really enjoyed that.

[BlueBee]

I was outside checking on the little devil when I saw this HUGE beast on one of my small birch trees (Betula Nigra 'Fox Valley').

[boca]

http://en.wikipedia.org/wiki/Polyphemus_moth

The caterpillar of the Polyphemus Moth can eat 86,000 times its weight at emergence in a little less than two months.

Your birch tree will be not enough.

[MrILoveTheAnts]

Anybody know what this little devil is?  He's on a sumac bush.

That looks like the Hickory Horn Devil, Citheronia regalis. Also called the Regal Moth. It's a threatened species though I think there are a few programs to rear and release. Despite how evil they look it's best not to kill them.

If you're concerned about the particular tree it's eating then, consider simply removing it (nudge it with a stick into a container) and put it on an adjacent: Ash, Butternut, Cherry, Cotton, Hickory, Lilac, Pecan, Persimmon, Sumac, Sweet Gum, Sycamore, Walnut, Maple or Oak.

http://bugguide.net/node/view/3559/bgimage

The adult form is very pretty and uncommon to see.

[MrILoveTheAnts]

http://en.wikipedia.org/wiki/Polyphemus_moth

The caterpillar of the Polyphemus Moth can eat 86,000 times its weight at emergence in a little less than two months.

Your birch tree will be not enough.

I agree that this is a Polyphemus Caterpillar, Antheraea polyphemus. But I think you exaggerate about it eating the whole tree. They barely weigh anything the first 2 or 4 weeks and at that age one still can't consume an entire Oak leaf in a day. The one pictured looks older than that and can probably eat a few Oak leaves (as an example plant) in a day but nothing to noticeable. By the end of it's life cycle it may have stripped a small branch of it's leaves but over a two month period that's nothing the tree can't simply regrow.

Again if Mothra seems to be eating enough to make the tree unsightly I urge relocating it to another host plant. Use a stick or tongs, or snap off the part of the tree it's on and put it in a container. Host Plants include: Apple, Ash, Birch, Dogwood, Elm, Hazel, Hickory, Maple, Oak, Rose, and Willow, with Birch, Rose, and Willow at the top of their menu. I emphasis not touching them with your hands as the hairs can be irritating and sometimes cause allergic reactions.

Another idea would be to keep it in a terrarium where it can't escape and feed it like a pet until it's hatched out from it's cocoon. The adults are quite pretty and don't feed. All the eating these giant silk moths needed was done as a caterpillar. They don't drink water either, they get their moisture from eating fresh leaves. The adult moth only has about 2 weeks to do it's thing, mate, and if female, lay eggs before dying. Best to release once they hatch from their cocoon. In this way you can select which leaves it eats off your tree, perhaps from branches you were thinking of pruning this fall anyhow.

[BlueBee]

Thanks guys.  Don't worry MrAnts, I NEVER kill a cool caterpillar.  I have raised Polyphemus before but I have never seen one get this big before.  I raise them on Red Oak though.  Based on how huge this wild Poly got on the Betula, I may have to try to propagate that tree!

[MrILoveTheAnts]

Thanks guys.  Don't worry MrAnts, I NEVER kill a cool caterpillar.  I have raised Polyphemus before but I have never seen one get this big before.  I raise them on Red Oak though.  Based on how huge this wild Poly got on the Betula, I may have to try to propagate that tree!

Season might also be a factor. I know Luna Moths that over winter fed mostly on leaves that had fallen off the trees the previous fall, resulting in a much smaller adult than typical. Not sure if this applies to other moths though.

[BlueBee]

That huge Polyphemus caterpillar spun a cocoon a day after I snapped the photo above.  I've got the other beasty protected with tulle.  Don't want the birds or fishermen to get him :) 

[AllenF]

I think it is too late to use that little devil for fish bait.

[BlueBee]

A devil update.  The thing has just shed its skin and is now the size of my index finger! 
You can see its old skin behind it.  Kind of cool how the old skin from its horns still holds structure. 

[twintrades]

Cool looking bug. Cant wait to see what the green Monster turns out to be.

[Riggs]

I think it is too late to use that little devil for fish bait.

I think it'd scare the fish off now... thats an impressive looking catapillar.

[BlueBee]

Mothra is now bigger than my middle finger and shows no sign of slowing down.  In the movie Jaws, there was that famous the line "we're going to need a bigger boat".  Well, I'm going to need a bigger tree!

The devil has taken on some new colors since his last molt.  Check out those horns.