there are HUGE green caterpillars eating my tomatoes!

Yesterday I saw something that I have never seen before in my life. Huge, green caterpillars on my tomato plants! I never thought I'd spot the biggest bugs of my life in Colorado!
My attention was first drawn to the plants when I noticed tiny droppings around the base of the containers (20" pots). Some areas of the plants looked like the leaves and stems had been nibbled. I finally noticed several, huge green caterpillars clinging to the stems. They were so well camouflaged that I have to be about 6" away to notice them.
Here are some close-ups of the buggers:
http://home.attbi.com/~stephen.and.kim/1.jpg
http://home.attbi.com/~stephen.and.kim/2.jpg
http://home.attbi.com/~stephen.and.kim/3.jpg
Anyway, my questions are:
1. What are these things? Where did they come from? I planted the tomatoes in pots with store-bought potting mix. Did they arrive by air?
2. I pried 7 of the buggers off my plants, but couldn't find any more. What can I do to to prevent them from coming back?
3. Are they poisonous, given that they are eating poisonous tomato plants? Will birds or other predators go after them?
Cheers, Stephen Boulder, CO
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Tomato Horn Worms, pick 'em off by hand and stomp the suckers flat.
Dave
On Thu, 28 Aug 2003 03:30:26 GMT, "Stephen Younge"

Dave Fouchey, WA4EMR http://photos.yahoo.com/davefouchey Southeastern Lower Michigan 42 35' 20'' N, 82 58' 37'' W GMT Offset: -5 Time Zone: Eastern
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Ewww! I've stepped on one of those by accident and it sounded, looked and felt gross! Just a warning. LOL
-- Lisa
wrote:<BR><BR>&gt;Yesterday I saw something that I have never seen before in my life. Huge,<BR>&gt;green caterpillars on my tomato plants! I never thought I'd spot the biggest<BR>&gt;bugs of my life in Colorado!<BR>&gt;<BR>&gt;My attention was first drawn to the plants when I noticed tiny droppings<BR>&gt;around the base of the containers (20" pots). Some areas of the plants<BR>&gt;looked like the leaves and stems had been nibbled. I finally noticed<BR>&gt;several, huge green caterpillars clinging to the stems. They were so well<BR>&gt;camouflaged that I have to be about 6" away to notice them.<BR>&gt;<BR>&gt;Here are some close-ups of the buggers:<BR>&gt;
http://home.attbi.com/~stephen.and.kim/1.jpg <BR>&gt;
http://home.attbi.com/~stephen.and.kim/2.jpg <BR>&gt;
http://home.attbi.com/~stephen.and.kim/3.jpg <BR>&gt;<BR>&gt;Anyway, my questions are:<BR>&gt;<BR>&gt;1. What are these things? Where did they come from? I planted the tomatoes<BR>&gt;in pots with store-bought potting mix. Did they arrive by air?<BR>&gt;<BR>&gt;2. I pried 7 of the buggers off my plants, but couldn't find any more. What<BR>&gt;can I do to to prevent them from coming back?<BR>&gt;<BR>&gt;3. Are they poisonous, given that they are eating poisonous tomato plants?<BR>&gt;Will birds or other predators go after them?<BR>&gt;<BR>&gt;Cheers,<BR>&gt;Stephen<BR>&gt;Boulder, CO<BR>&gt;<BR><BR>Dave Fouchey, WA4EMR<BR><A href="http://photos.yahoo.com/davefouchey ">http://photos.yahoo.com/davefouchey </A><BR>Southeastern Lower Michigan<BR>42 35' 20'' N,&nbsp;&nbsp;&nbsp; <BR>82 58' 37'' W&nbsp;&nbsp;&nbsp;&nbsp; <BR>GMT Offset: -5 <BR>Time Zone: Eastern</BLOCKQUOTE></BODY></HTML>
------=
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What a waste of tasty horn worms. They make great dog treats!

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Look like monarch butterfly caterpillars. If they are, yes they are poisonous. As to how they arrived, did you plant from seed or buy the plants at a nursery? If bought the eggs were probably on the plants. I know birds will leave them alone, don't know about any other predators though.
If you put them in a jar with some branches and feed them you'll have some of the most beautiful chrysallis's when they get ready to go through metamorphosis.
Also, I think monarchs are on the endangered list but I'm not absolutely sure
Shell

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Tomato Horn worms, they will become a very large moth...the name escapes me. The worms grow up to 4" long

Pretty common predator. If you see one with white eggs standing all over its back, like so...
http://members.aol.com/digitalvinyl66/tomatostegosaurusworm.jpg
Don't kill those. The eggs are typically wasp eggs that feed on the horn worms. When the eggs hatch they eat the worm, then they spread out over your garden and do the same thing to all the others. I had only one in my garden...it had eggs. I left it, it vanished and I never saw another. Killing small brachnid wasps may allow the worms to multiply (eliminating natural predator).
Doesn't effect the tomatoes, but because of size and appetite will strip plants quickly. DiGiTAL ViNYL (no email) Zone 6b/7, Westchester Co, NY, 1 mile off L.I.Sound 1st Year Gardener
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in article snipped-for-privacy@4ax.com, DigitalVinyl at snipped-for-privacy@internet.com wrote on 8/27/03 9:15 PM:

That is a good photo!
Fortunately, I have not run across a hornworm this year. Unfortunately, I never saw one that looked like the picture.
Bill
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On Thu, 28 Aug 2003 03:30:26 GMT, "Stephen Younge"

------ Tomato Horn Worms! Yep, that's a huge bug here in NJ too!
Do you watch the TV show.. Fear Factor? Ocasionally they make the contestants eat tomato horn worms in the competition to win the $50,000. Imagine eating them? I hardly can stand picking them up and squishing them.

------ Nice pics! I liked how you showed the scale with the bugger posing with the pen. Very good!
---pete---
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If you spot another, and are anywhere in the Denver area of Colorado, let me know and I will gladly come and get him. I have been looking for a live one for two years to get a picture for our webpage, and of course, these are the first years that they haven't shown up in my garden! sed5555
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I'm surprised this is your first experience with the Tomato Hornworm. They are as common as butterflies. They definitely get very large and fat when they start devouring your tomato plants (stems, leaves and tomatoes). They have a voracious appetite and will target green or red tomatoes too. They are very lime green with little white marks on their backs and a red horn on one end. They tend to cling to the ends of the branches underneath. First thing in the morning is the best time to find them.
Anyway, they are not poisonous or dangerous; just a nuisance. If you see some with little white pieces of rice all over their backs, leave them. These white things are actually the eggs of a parasitic wasp and they are feeding off from the hornworm and will eventually kill the little devil. The parasitic wasp is a super beneficial guy to have around in the garden. I usually pick the egg laiden hornworm off the plant and relocate it somewhere else. Otherwise, pick off all the hornworms that you can find and kill them. You can also apply Bt Powder to the plants to kill any younger hornworms. It is an organic biological insecticide that targets just caterpillars and chewing larvae. I just had to apply some yesterday because my tomatoes and peppers were being chewed to death and I couldn't find them on the plant.
When my kids were in elementary school they would take a jar of hornworms with tomatoes and stems to school and the kids would get a big kick out of seeing how much they would eat overnight.
Good luck.
Penny Zone 7b - North Carolina

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Hi! What you have is hornworms; They eat both leaves and tomatoes. They work very quickly too! Hand-picking them is the best way to get rid of them. They usually appear at harvest time. I would also suggest a non-toxic spray Bacillus thuringenis ( available as Dipel or Thuricide) is effective. Good-Luck! Peppergirl http://hotcuisine.esmartweb.com /

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...

Facinating. I saw one of these on my tomato plant yesterday for the first time as well. Admittedly, this is only the second year I have planted tomatoes (or anything for that matter).
I was so freaked out by the worm that I stuck it on a pile of fireants. I know that sounds horribly cruel, and I actually felt bad afterward. Unfortunately, the only bug I can squish without tossing my tuna is the cucumber beetle (which I do with pleasure, I might add). What's weird is that an hour later, there were no traces of the worm. Did it escape alive? Surely not.
I would have tried feeding him to the geckos, but he was larger than any gecko I have seen.
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Well the" What are these things" has been answered, but "Did they arrive by air" hasn't, so ........ Yes, you are correct, they did arrive by air! The tomato hornworm is the larva of the tomato Sphinx moth She flies in and lays her eggs on your tomato plants and the eggs hatch into tiny caterpillars/larvae. These grow Rapidly into Hornworms. They willl eventually crawl into the ground below and form a very large pupa which will become another moth, etc. There are usually two generations a year.
Here in Northern Calif, the scrub jays love to eat them. I have seen evidence of the caterpillar's presence, but the jays remove them before I do.
The scientific name is Manduca sexta.
Emilie NorCal
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Thanks for those great links on horn worms!

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