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texaskittysa

Asp caterpillars

texaskittysa
9 years ago

I just spent the morning checking the neighbor's Hackberry that hangs over our driveway for asp caterpillars and killed 5. This was after my brother had one drop on him yesterday. I live south of downtown San Antonio and it has been years since I've seen this caterpillar in any numbers. For those new to this area and unfamiliar with this caterpillar, their sting is very painful and can require a trip to the ER if you are sensitive to its poison. Speaking from personal experience, their sting is worse than a bee or wasp. They usually come in grey or yellow and resemble a tribble for those Star Trek fans or are almond shaped with wavy fur-like bodies if you're unfamiliar with the reference. If you have kids or grand kids, please make sure they know not to pet the pretty caterpillar, any pretty caterpillar. My question to the group is, do you know anything I can spray in the Hackberry trees that my neighbors have let grow along the fence lines that will kill this devil's spawn? I'm considering straight orange oil or neem oil in the hopes of coating them enough so they die. At this point, I really don't care how much foliage I burn off of these trees. Spiders, wasps, bees don't bother me, but these things make my skin crawl.

Comments (10)

  • roselee z8b S.W. Texas
    9 years ago

    Dang, I'm sorry to hear about that. I've only seen one and that was a number of years ago. It had fallen out of a neighbor's Arizona ash tree and she called me over to look at it.

    I just googled 'eliminating asp caterpillars' and there isn't much you can do. Spraying with anything in hopes of killing them only kills their predators, mainly the tachinid fly, which increases the number of asps.

    Here is a link that might be useful: Scroll down and read the part in red about spraying for them ... ...

  • texaskittysa
    Original Author
    9 years ago

    Thanks, Roselee! That is a good link and pretty much is what I found on the Internet as well in researching what to use to kill them other than a flamethrower. I was hoping someone might have found something that worked for them. I'm still thinking of giving orange oil a try, particularly on the one tree over our driveway. The ones that I killed are all about an inch long, big, fat and evil. They'll be leaving the trees soon to spin their cocoons and at that point they can be anywhere. I don't want these guys turning into moths to lay more eggs. I've found an asp in my garden of Eden:(

  • texaskittysa
    Original Author
    9 years ago

    The last three days have been very interesting. Yesterday I killed 18 asps, the day before that 10, and on Saturday 6. To say I have an infestation is an understatement. Orange oil works but it has to be straight out of the bottle and you have to coat them with it. After 3 days of using my preferred method of picking them off and squishing them, I resorted to Spinosad and when that ran out, a good dose of Ortho Bug B Gone. One or the other had some effect, since we saw their dead bodies falling out of the neighbor's trees. The problem is, their venom doesn't die with them and they can still be a problem, even dead. They seem to prefer hackberries, but also love my rose bushes, but are not plant specific. So far I've pulled them off of a weeping Mulberry, an orchid tree, a beauty berry bush, turk's cap, and a clock vine. Now we're finding them on statuary, planters, and pots as they come down out of the trees

    For anyone who is curious, here are some photos. Can you see the three in this picture--a pale yellow, a golden yellow and a silver grey?


    This one is charcoal grey. These blend in so well with their surroundings.


    Finally, a bright yellow one...Some are even striped like a tabby cat.

  • roselee z8b S.W. Texas
    9 years ago

    Oh my!!!! That is some infestation you've got going on. Actually it's more like a plague. How is it going?

  • texaskittysa
    Original Author
    9 years ago

    Plague is a good word for it! I have never seen so many. After days of killing them wherever I found them, I brushed one just slightly and got stung pretty good. My feral momma kitty stepped on one, I think, since she limped for days before getting better. I finally resorted to Ortho's Bug B Gone, since it seems to kill them. I have sprayed the entire front and back yards and the neighbors hackberry trees on both sides several times. The following days, I killed three that were on the side of the neighbor's house and were beginning to form their cocoons. Since then, I haven't seen any. I'm thinking that this must be related to the weather and the perfect combination of temperature, humidity, and food source. I'm praying that this won't be the norm every year. I've heard that the trichogramma wasps will parasitize them, so I will try that in the spring since the asp can appear in both spring and fall. Until we get our first freeze, I'm going to be extra careful in picking up pots or what I touch or sit on. Being stung is not fun!

  • missymoo23_(z9a_Tx)
    9 years ago

    One of those fell onto my daughters bicycle handle a few weeks ago....it was "parked" underneath one of the oak trees. She put her whole hand right on it, not noticing. She hasn't touched her bike since and her hand and lower arm hurt for 36 hrs. I'm glad to see this post...I was really worried!

  • phoenix7801
    9 years ago

    BT worm killer should take care of them. Itll be alot safer since technically youre creating a mist in the tree.

  • wantonamara Z8 CenTex
    9 years ago

    Tricogamma wasps work great on oak leaf rollers . I got them from Arbico organics and I think as long as you do not continue spraying, their population will multiply and keep these eggs under control.. My trees were stripped by a plague of the oak leaf rollers that covered miles of territory around me for a couple of years. After the first onslaught I put some out and they did not come back on my yard but my neighbor who sprayed had them again thew next year. I think these plagues come and go. That might be hopeful thinking.

    Here is a link that might be useful: Arbico Organics

    This post was edited by wantonamara on Sun, Nov 30, 14 at 18:18

  • wally_1936
    9 years ago

    I do not know but maybe my wasp populations has something to de with them no longer being here.