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traceyleeokc

Sunburnt Hornworms?

TraceyOKC
11 years ago

I had a couple on different plants that I had been monitoring. I planned to move them if the plants were suffering. Yesterday afternoon I checked them to find them brown, I thought I was looking at sticks. Then I thought they were dead. This morning they were only half as brown and moving more. This evening back to normal. They are big guys w stripes and spots. Their plants were in very hot locations. I used to get rid of them but I am trying to live with them. (Of course they will have to follow the rules!)

Do they turn brown normally?

Comments (17)

  • susanlynne48
    11 years ago
    last modified: 9 years ago

    Tracey, the larvae can turn brown, but I have never seen it in my hornworms. Many sphinx larvae turn a brownish color when they are about ready to pupate especially. However, it has been so hot and dry, I don't know if environment can affect coloration or not since it hasn't been this hot since I began raising them. IMHO I would give them some shadier conditions if you can. If not, they will probably be okay.

    Susan

  • Okiedawn OK Zone 7
    11 years ago
    last modified: 9 years ago

    Sometimes they do start out their natural green color and then turn brown and I think one reason it occurs is because they've been parisitized by predatory wasps and are dying from the inside out.

    There is a brown form of tomato hornworm that hatches brown but it is fairly rare. I believe it may be some sort of genetic mutation because you'll have several green ones and then a brown one of the same size, as if they likely came from the same batch of eggs.

    There are some other hornworms that are naturally brown, like the one that feeds on elm trees. Hornworms come in a wide range of colors. We just think primarily of the green ones because that's what we see most often in our veggie gardens.

    We grow a lot of trumpet creeper vines for the hummingbirds and we have Pandora sphinx cats on them. Sometimes they are green, but sometimes they are brown.

    I'll link a page with photos of some of the different kinds of hornworms.

    Here is a link that might be useful: Hoirnworm Images

  • susanlynne48
    11 years ago
    last modified: 9 years ago

    Dawn, I don't think that paratisation causes any of the sphingidae tribe to turn brown, but it's possible as more research comes to light on the subject. It does have something to do with genetics, but it has not been found to be of any concern regarding the health of larvae, to my knowledge. Most just have a natural inclination to turn brown, while others remain green. There are many variations in coloration of several genus of sphingids. Hyles lineata, aka White-Lined Sphinx, for example, exhibits so many variations, it's hard to compile a library that one could rely on to adequately ID it, except for the larval food plants known to us, and even that could vary.

    The Elm sphinx, or Four-Horned Sphinx, Ceratomia amyntor, which I have raised, is the sphinx found on Elm, and they exhibit both brown and green forms.

    Larvae that consume Trumpet Creeper, or Campsis radicans, are the Paratraea plebeja, and Pandora sphinx, or Eumorpha pandora, eat plants in the grape family, e.g., grape vines, Virginia Creeper, Ampelopsis. I have raised both of these sphinx moth cats as well.

    Virginia Creeper is a huge larval host plant for sphinx moths as well as other moths as well, such as the Eight-Spotted Forester, a beautiful day-flying moth that is black with white spots, and furry red legs. People often mistake it for a butterfly.

    A few years ago, I found 1st instar larvae of the Snowberry Clearwing sphinx on my Honeysuckle, one of its larval host plants, that were brown. I forwarded my images to Bill Oehlke at Bizland for his sphinx moth and larvae collection database, and he has loaded them on his website for reference. It was originally thought that the larvae emerged and quickly turned green after its initial feeding on the foliage, but no one had a photo of the early instar brown form. It is rare, but it did not affect the health of the larva. I've raised and released several of these pretty little bumblebee mimics.

    I adore all the sphinx moths and have raised 13 different genus/species here in my own yard alone.

    The caterpillars can be destructive, but the adult moths are highly beneficial. Since you can't have one without the other, I include other Solonaceae plants for my Tobacco Hornworms, nanmely the Datura.

    Susan

  • Okiedawn OK Zone 7
    11 years ago
    last modified: 9 years ago

    Susan, What I mean is that as they're dying or perhaps after they're dead, they can turn brown. (I don't touch them to see if they are dead or alive.) I don't know if those brown dead ones are hornworms that would have turned brown anyway or were more brown to begin with, or if all of them turn brown if they die before they can pupate.

    You probably don't see as many dead ones as I do since you are in a more civilized area. Our fields are often overrun with these things in autumn as the native food sources dry up and die, especially in a drought year. It is not at all uncommon to see them crawling across the road, presumably looking for greener pastures, or traveling up the road, though they generally don't last long if they're trying to share a roadway with cars.

    I don't see many being parisitized in summer, for example, but by fall when there's less green cover for them, I think the native predatory wasps can find and attack them more easily. Also it may take until fall for the wasp population to get big enough that I'm seeing it affect the cats.

    I still am amazed that with all the caterpillars I see in the fields, I just don't see them in my garden. I had about 300 tomato plants this year, and the only hornworm I found in my garden was a cherry hornworm, and it was on the ground and not on a plant. I never saw a tobacco or tomato hornworm on a tomato plant or tobacco plant or a datura and didn't have foliage damage on any of those either. It seems crazy to have the moths all over the place, and not have the damage on my tomato plants, but I am not complaining.

    I like the moths when I see them, and I tolerate the cats in order to have the moths, but if they damaged my tomato plants like they damage some other peoples' tomato plants, I'd likely be out in the garden killing the caterpillars myself. Luckily, since they have plenty of native plants they seem to prefer, they tend to leave my garden plants alone.

    I've linked a page that has a photo of the brown ones that are like the dead ones I see, usually in late summer or in autumn. The ones I see often are more torn up than the one in the photo. I'm not sure if they're torn up from predation or wind tearing them up after they're already dead or what.

    Dawn

    Here is a link that might be useful: Example of a Dead Brown One in 5th Photo

  • TraceyOKC
    Original Author
    11 years ago
    last modified: 9 years ago

    I managed to get a picture of one today. I didnt have time to look for the others. This one is on the chainlink fence of the old dog kennel, with a tinroof, but it has a large shade tree.

  • Okiedawn OK Zone 7
    11 years ago
    last modified: 9 years ago

    That's a great photo of your brown hornworm. Susan's gonna love it.

    It is too bad they all are not brown because it would make it a lot easier for gardeners to spot them on their tomato or tobacco plants.

    Here is a link that might be useful: Bugguide.net's photo of a brown hornworm

  • susanlynne48
    11 years ago
    last modified: 9 years ago

    Is the hornworm eating tomato foliage or something else, Tracey? It doesn't look like tomato foliage to me. Is it Morning Glory leaves it's eating? If so, that would be an Agrius cingulata, or Pink-Spotted Hawk Moth you've got there. Hornworm is a general term used to describe any member of the sphinx tribe. Unforunately, not all "hornworms" have horns. Some lose their horns in later instars of growth, leaving only a slight hump or a circular spot where the horn previously was. You kinda get so you can recognize a "hornless" hornworm eventually.

    Dawn, the second group of photos is the "brown" -more of a pinkish brown -I thought you were talking about, which is the color most turn when they are preparing to pupate.

    That a beautiful photo of the Tomato Hornworm on Bug Guide. I just have seen very few sphinx in the garden this year. I actually saw more last year when we had the extended drought and heat than I'm seeing this year. It was 112 degrees here today! Too hot to be outside at all, and yet I watered, I am planting Zinnia seeds in some of my tomato pots. I figured if the tomato plants die, at least I'll have some pretty flowers for the butterflies.

    Susan

  • TraceyOKC
    Original Author
    11 years ago
    last modified: 9 years ago

    Susan you are right, he is on the Morning Glory. I have some on the Moonflowers too. You inspired me sometime ago to become more familiar with the purpose of caterpillars and their life cycle.

    I did raise 3 this spring, it was fun. I used to think caterpillars just found my plants and laid eggs to have more cats to eat my plants. I just never really thought about how the cycle works.

    I had lots of tom transplants this spring and put 2 of the extras in an out of the way spot for the cats to have. I haven't had many cats this yr. but I am glad I had a plan and if they do too much damage to the MG or MF ill move these guys. I like butterflies and the Sphinx moths...I saw my first one this spring. I thought it was a hummingbird. I really enjoyed watching him.

  • susanlynne48
    11 years ago
    last modified: 9 years ago

    Thanks, Tracey! It's nice to know that I may have inspire someone to enjoy these interesting and beautiful moths as much as I do!

    I've attached a link to Bill Oehlke's website regarding this particular sphinx. As you can see, they are pretty, and have interesting color morphs. Follow some of the links to see more images of Agrius cingulata.

    Susan

    Here is a link that might be useful: Agrius Cingulata aka Pink-Spotted Hawkmoth

  • Okiedawn OK Zone 7
    11 years ago
    last modified: 9 years ago

    Susan,

    That is too hot. It hit 112.9 here and I was out every 20 or 30 minutes trying to keep the chickens cool by making them mud puddles, taking them almost-frozen melon to eat, etc.

    I am seeing lots of the various sphinx moths here in the evenings, but not a lot of hornworms on plants. Of course, I am not exactly out there in the garden looking for them either in this heat. Mostly I am just seeing sulphurs flying around the garden. Other than sulphurs during the day and sphinxes at night, butterfly and moth activity is low. I have seen one buckeye this week. Maybe they're lying low in this heat and staying in shaded areas as much as possible.

    Because I have daturas, nicotianas and four o'clocks in bloom in the evenings, the sphinxes are all over that area of the yard. During the day, I'm only seeing sulphurs because they are visiting the zinnias, morning glories and melon flowers.

    I hope we have more butterflies in the fall.

    I do have zinnias in some beds, but since I stopped watering, I am not sure how long the flowers will last.

    On our entire property, there is exactly one native sunflower plant in bloom, which is pitiful. Usually there's dozens. I have no idea what flowers the butterflies will have for the rest of this growing season. The goldenrod plants in the fields have made a half-hearted effort to bloom, but the blooms and plants cannot take this heat and are fading fast. We have huge stands of liatris in the fields, but they are starting to brown out and go dormant without even blooming. Things around here are looking worse and worse every day.

    There's so little water that the dragonflies follow me around the yard, waiting for me to turn on the water hose and either make them a big puddle in the driveway or turn on the sprinkler for a few minutes to wet the grass for them. We may think the dragonflies don't even know we are there, but I know they watch me and follow me and expect me to provide them with the water they need and want. Sometimes they land on my shirt or on my arm. They definitely expect me to do something to help them, and I do what I can. It is pretty bad when the dragonflies cannot find water.

    Dawn

  • TraceyOKC
    Original Author
    11 years ago
    last modified: 9 years ago

    Great info on that link..thank you. It said they start green turn brown and then yellow. Sounds like my guys.

    I started lots of flowers for the butterflies this year. I need to study more go see which ones attract and what they attract.

    I have zinnias also they still are getting the most attention still. Are the guys that get on my salvias and petunias caterpillars? They are kind of small. Do certain worns eat above ground? I don't mind letting them eat for a while since I know they will go pupate (sp?) in time. But if it is a worm that will eat and eat, and make more worms, well it has to go.

  • Okiedawn OK Zone 7
    11 years ago
    last modified: 9 years ago

    In my yard, the zinnias are getting the most attenion but the verbena bonariensis get a lot of butterfly attention too.

    Anything eating your salvias and petunias are likely to be caterpillars. The answer about what they might be would vary depending on the month when the plants were eaten. If it was during the time frame, roughly March and April and maybe into May, when the climbing cutworms were active, it could have been the cutworms. Susan will know what usually eats salvias. Nothing eats my Laura Bush petunias so I can't help you there.

  • susanlynne48
    11 years ago
    last modified: 9 years ago

    Southern Pink Moths are pests of Salvia. People think they are pretty little moths because of their unusual pink coloration, but not me. They practically destroy my Salvias, and in particular, the blooms. Grrrrrr.

    Petunias could be almost anything. Since they are in the Solanaceae family, you could find a hornworm on them, but more likely some kind of "generalist" moth larvae.

    I do not use pesticides or even organic IPM in my garden, because it is a wildlife garden - wildlife meaning I grow larval host plants for butterflies and sphinx moths, berries and seeds for the birds, and hummingbird nectar plants and bee plants. But, this summe I had the Genista moth caterpillars attack my beautiful Baptisia var. minor again, so it sprinkled it with BT. Bad momma, I know. But, I am never sure if the Baptisia will survive consistent, long-term defoliation from these cats, so this time I broke down and used the BT.

    Dawn, some of the flowers in the yard are really suffering from this extreme heat by producing watered down, pale blooms, e.g., some MGs, butterfly bushes, Cleome. Some plants are producing smaller blooms or fewer blooms, or not blooming at all in this heat. I wonder if I am putting off the inevitable by even watering them some days. I have never seen anything like this since moving to Oklahoma in 1975. How folks survived the Dust Bowl, I don't know. They didn't have AC back then, that's for sure. Of course, I know most of us are so acclimated to air con that WE wouldn't.

    Still, I am out there every morning, faithfully watering, deadheading, watering down to cool them off for a short while, saying encouraging words to them like "this, too, shall pass" - lol! I don't think they believe it. Yes, I talk to the plants.

    This is a true test for our power grid, huh?

    Susan

  • Okiedawn OK Zone 7
    11 years ago
    last modified: 9 years ago

    Susan, My flowers are doing the same. It is normal for the flowers to fade and even change colors in the extreme heat. I grow a spring- and early summer-blooming Texas Bluebonnet called "Alamo Fire". Normally it has red flowers. I mean really red. This year? They started red and quickly faded to a pale pink that is almost white. As of last week they still were blooming. To have them still blooming in this heat astonishes me. Of course, since I stopped watering, they're likely dead and brown by now. My rose-colored cleome is pale pink, etc.

    Whether it is worth watering is something only you can decide. I have stopped watering everything in the big garden because it was a losing battle and all I was doing at this point was providing the grasshoppers with a meal. With annuals, you might decide it is not worth it to keep watering. With perennials, or with annuals you want to reseed, I'd keep watering as long as the budget allows and as long as watering restrictions allows.

    It just kills me to even look at my big garden because it looks so bad.

    Let's be realistic. Many folks did not, in fact, survive the dust bowl. Many died of dust-related lung disease. Many pretty much starved due to a lack of food and wasted away and became weak and then the flu or pneumonia or something else got them. I've never seen numbers for the fatalities attributed to the dust bowl, but I bet it would shock us.

    Many who survived were very tough survivors. Often, they canned weeds (like tumbleweeds) in order to have food for winter after the gardens failed. Can you imagine?

    The heat? I cannot imagine it. I cannot imagine what it felt like, how they suffered, etc.

    We are just wimps by comparison and, you're right, we couldn't do it. We are too used to all the modern conveniences. My dad lived through the Dust Bowl and he didn't ever, ever like to talk about it. The memories were too painful.

    I would water and do what I could for as long as I could. I am trying to preserve a green zone around the house for fire safety and it is not easy. I not only talk to the plants, but to the butterflies, bees, dragonflies, birds, etc. Is there something wrong with that? lol I am so happy to see my four o'clocks blooming in the evenings that I just want to hug them. Without water, though, they will go dormant by the end of August. They're too far from the house for me to be able to claim they are part of the green zone around the house.

    My trees look worse daily. There's too many trees and water is too expensive. I am doing the best I can to save what I can and I will be REALLY MAD if fire comes through here and takes out my plants after I have worked so hard to get them this far.

    August is going to be incredibly bad, both in terms of fire, fire danger, and uncontrollable wild fire, and in terms of heat and drought stress on the plants, animals and people. For whatever reason, this year feels worse to me than last year. Maybe it is because I am a year older.

    I have had a buckeye in my kitchen for two days, just hanging on the wall. I don't have the heart to make it go back out into the heat. Isn't that crazy?

    Dawn

  • susanlynne48
    11 years ago
    last modified: 9 years ago

    Ah, how nice for the Buckeye! I think they are such pretty butterflies, and I grow Dooryard and Lanceleaf plantain for them. The cats also eat Snapdragons, Diascia, Mexican Petunias (Ruellia), Agalinis (Cudweed), Twinflower (Dyschoriste), Toadflax (Linaria species), Russelia specias, and in rare instances, Butterfly Bush. Obviously, you won't find Snapdragons around in this heat.

    My only butterflies right now are Gulf Frits - laying eggs like crazy on the passion vine -, Cabbage Whites, Checkerspots, Crescents, Skippers. Not seeing many mid- to large-size butterflies at all. Cool thing about the Gulf Frits is that once they find your garden with host plants, they will stay until fall when they migrate back south.

    I gave up watering this morning because it just got too hot, and I was beginning to feel faint and dizzy. I was drinking plenty of water, but, let's face it, it's dangerously hot out there. The potted tomtos will suffer, but the rest of the garden should be okay. Some of the annuals, I have to water, like the Sunflowers, Zinnias, Tecoma, Porterweed, Hamelia patens (these last 3 are in pots so I have to water them pretty much daily), milkweed 'Family Jewels', MGs, Okra, Squash, etc. The Passion Vine, P. incarnata and P. 'Lavender Lady', are very drought tolerant, as well as Maximilian Sunflower, Salvias, herbs like Oregano, Fennel, Rosemary; Cosmos, Golden Crownbeard, Asters, but in this extreme heat, they need a drink now and then, too. All my perennials get watered regularly. The tomatos are just about a done deal. I may pull them up and put some of the ones I've got in small pots in the bigger ones, or buy a couple wherever I can find them. They are pretty much stalled out right now due to the heat, even though I've watered and shaken them practically to death.

    But, I have to take care of myself and watering until 11 or 12 noon, is just too long to be out in the heat when it hits 100+ by 9 or 10 a.m.

    You take care of yourself, too, Dawn! I watched part of the Norman and Luther fires yesterday on the news. I really feel for the folks who lost homes and property, and for the firemen who valiently fought those fires. I fear it is only the beginning this month, though. I'll be praying for all of our firefighters.

    Susan

  • Okiedawn OK Zone 7
    11 years ago
    last modified: 9 years ago

    Susan, We put the buckeye outside early this morning because none of her favored plants are growing in my kitchen.

    There is no shame in giving up in this heat. There's only so much that anyone can bear. It is dangerously hot. I have been trying to be back inside by 9 a.m.

    I have the Norman/Noble/Slaughterville fire channel on my computer so I can listen and try to understand what is going on. Our fire dept. sent a truck up there this morning as part of the Love County Task Force responding to their request for mutual aid. I wish we could have sent a bigger task force than the 3 trucks that went, but we have a Red Flag Fire Warning here too, so couldn't send too many or we wouldn't have enough trucks here if a fire breaks out.

    I have received text messages from Chris and Tim and it sounds likes an incredibly aggressive, persistent fire. They have run out of adjectives to describe it. Chris says it is the worst wildfire he's ever seen in person, and he has fought some big ones in southern OK and in the western OK area near Lawton in previous yeas.

    Anyone reading this should know that I have listened to the fire response on the Cleveland County radio system online ever since this fire started and I am so very impressed with how hard everyone is working, how well they are working together and how calm and organized they are in the face of insurmountable odds. Every one of us should be proud of the work they are doing. I'm hearing fire units there not just from every department you can imagine in central OK, but from southern, southeastern and eastern OK. I know that firefighters in other areas cannot send help to Cleveland County because there are many other fires, some of them equally large and equally hard to stop at this time. They are doing a great job in the face of a fire that is almost unstoppable. If it could be stopped, they would have done it already. Eventually they will get it stopped, but this is one of those one step forward, two steps back types of situations. Their Incident Commander is doing a great job. The problem is that everything is so dry and there is not enough water in this whole state to put out all those cedar trees, so the fire spreads from one to another. They are trying to protect and save homes, but there again, the lack of water is tough. From what I hear, there is a huge reliance on water tanker trucks, so I think there must not be many, if any, fire hydrants out in those rural areas (which is common in this state).

    I'm here at home hoping a fire doesn't break out in our county today, and just trying to keep the pets cool inside and the chickens cool outside. That's all we can do on a day like this...just work on surviving it.

    Around me, I see gardeners letting their gardens die, and I don't blame them. We need to be conserving water for future fires. Melons that are not yet ripe enough to harvest are sunburning in the fields. This is an awful summer. I want a "do-over" with more moderate temps.

    I am getting tired of saying "maybe next year will be better". Those words get old when the next year is not better!

    Dawn

  • susanlynne48
    11 years ago
    last modified: 9 years ago

    Dawn, when you say that we all need to be conserving water, I think about last week when the city's water main broke in my front yard. That was very early last Tuesday morning. A guy from the City stopped by about 7:00 a.m. to check it out and called it in for repair. Well, no one came until Thursday late afternoon. Meanwhile, the water ran and ran and ran down the street. It wasn't a gusher, but it was close. I called them a couple of times to remind them that "water was awastin'. Their response was that they have 48 hours to respond. You'd think they might have contractors on hand to call when they need the extra help, in order to prevent this water waste, but apparently not. I can't imagine just how much water runoff the City had from just my little main, but it sure seemed like a ton.

    It's funny how the City wants us to conserve, but they don't implement any conservation in their own backyard.

    Susan

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