Friday Beetle Blogging: Palo Verde Beetle

Spread the love

Derobrachus hovoreiPalo Verde Borer
Cerambycidae
Tucson, Arizona

Every June, hundreds of thousands of giant beetles emerge from beneath the Tucsonian soil. The enormous size of these beetles- up to several inches long- makes them among the most memorable of Tucson’s insects. They cruise about clumsily in the evenings, flying at eye level as they disperse and look for mates.

Palo Verde beetles spend most of their lives as subterranean grubs feeding on the roots of Palo Verde trees. Adults emerge in early summer, usually ahead of the monsoon, and by August they are gone.

It is still a bit too early in June to see them, but in anticipation of this year’s emergence I am posting photos I took in 2006.

photo details: Canon 100mm f2.8 macro lens on a Canon 20D
top photo: indirect strobe in a white box
bottom photo: natural light at dusk

87 thoughts on “Friday Beetle Blogging: Palo Verde Beetle”

  1. To Anonymous,

    Maybe I’ll see you there! Would you mind telling me again what purpose they serve, besides killy Palo Verde trees?

    Thank you!

    PS- You sound like a really pleasant person. 🙂

    1. Dear Terrified-

      Palo verde beetles knock out older Palo Verde trees, allowing the young PV trees, mesquite trees, saguaros, opuntias, and other desert plants a better chance to grow in their wake.

      They inhabited the region tens of thousands of years before humans showed up.

      It isn’t the Palo Verde beetles that have to justify their existence. They live in the desert.

      What’s your excuse?

  2. Hi All,

    I too have had a few frightening experiences dodging these flying beetles and even been hit in the head once by one. I don’t bother killing them, they die on their own and on the other side of my home where my dog run is, my Dachshunds catch and kill them. They haven’t been harmed by them either.
    They are just a part of the nature scheme here and I agree with Anonymous and also Myrmecos that they should be left alone.

    Once you get past the shock of seeing them, they really are quite grand and amazing to see. There are a lot of other insects and snakes that are a lot more dangerous around us, but they all belong here and serve their purposes.

    When I lived in Gilbert, we had a house-guest that absolutely terrified me. It was a tarantula wasp and that thing was a twitchy 5 inches long and purple/blue florescent with antenna that were unbelievably long. Have any of you seen one of them? It wouldn’t leave the underside of my patio and would frighten me so much when it flew out and back. Sometimes it would land on our patio table and I would run into the house and try and get my mini Dachshund inside with me because she would go after what was scaring me. These wasps kill tarantulas and lay their eggs on them. Then the larvae feed on the paralyzed tarantula and then mature and go off on their own. I think some may have replaced their mother at my home. I looked them up to see if they could hurt us and found out that between 1 and 10 on the sting-o-meter scale, they were a 10, so don’t even mess with them.

    When they’re there, just try to avoid them. Like dive bombing bumble bees. 🙂 or stay in the house when there’s just too many to deal with.

    Take a tranquilizer and go and watch some tv or clean the house.

    Ciao for now 🙂

    P.S. The best animal to protect you from these pests is a Cornish Rex Cat, try one, you’ll be amazed and you’ll love it!

  3. My son lives in scottsdale. He recently sent a photo of one of these big bugs to his sister and told her it was his pet! Not knowing much about Arizona, she believed him and being an animal lover was glad to hear her brother had gotten a pet!!!!!!

  4. Yesterday I found one of these guys in my chicken coop, but it was so big the chickens were scared to go near it! I picked it up by the torso to carry it out, but it twisted around with surprising flexibilty and bit me solidly on the finger. It left two sizeable vampire ish bites which swelled up a little and hurt to the touch. But I let the little guy go free. Today I found him dying on the porch…… Though they do live a short life after emerging…… Vicious mandibles aside, they are beautifully fascinating creatures.

  5. Just saw first ones of the season last night in east Mesa. I consider myself a pretty tough guy and not many things “scare” me but I hate these things. They petrify me. I will not go outside after dark in July for any reason. Like everyone else says they seem to be attracted to light. I have been avoiding these bastards for the last 15 or so years since the first one dive bombed me. I will be getting some raid and hosing all the door and window openings. Never had one in the house and dont want to. Between the heat and these monsters, I have vowed that this is my last summer in this state. By the way, great blog.

  6. I’m from Mississippi and have found three in the past week! Yes, every description of this insect is to an exact. Is this possible!?

  7. So does anyone know if they can be consumed by Humans? I live in Spokane Wa and I found one here and Im daring a friend to eat one (like a survivor food).

    Are they poisonous

  8. I saw my first P.V beetle 2 wweks ago while watering our Palo Verde tree (go figure!) We have LOTS of holes surrounding our tree and never knew what it was. When I filled up the holes, a beetle emerged slowly! I was horrified and sprayed it with 2 cans of bug spray. The next day it was gone, and I think it survived now knowing how difficult they are to kill. I have since done LOTS of research on these guys and it’s gross. They start as borers (eggs) that eat the roots for 2-3 years. So you don’t even know they are there! Then they emerge as adult beetles In late June & July. As adults, they don’t eat anything–they survive off the roots they ate as borers so they don’t live long.

    Our strategy now is to put water in the 10-20 holes, draw them out and my husband will smash them. We killed 7 last night and most had the white eggs in their bodies. Even after smashing them, their bodies twitched a while. I hate to kill them, but reporducing into an infestation is not an option.

    We are even contimplating moving out of this house since we have even found holes around the base of our brick house, and along the brick wall. I’m most concerned about being a breeding ground for these horrific beetles. How do we kill the borers??? That’s the source of the problem. I don’t want them to kill our tree and other trees, and I REALLY don’t want them to reproduce into a bigger problem next year.

    **–>Any suggestions on how to kill the borers in the ground? Bleach? lighter fluid? I know it seems silly, but I will do anything–these are tormenting and traumatizing me and our kids.

    1. Lance William bengs

      I have been living with these beetles my entire life I hate them they have become my arch-nemesis if there is such a thing as past lives I believe that I was devoured by these creatures they are hard to kill even after you step on them they still keep going very hard exoskeleton bleach will stun them but does not kill them Flames are your best option if you grab a container of hairspray and a lighter and torch them their bodies will explode one season me and my father killed 27 of them we used to fill the holes with water as well and as they came out we squashed them if you get them in a puddle of bleach they will eventually die but it takes a while I don’t know of any spray or insect killer that will take care of them their only purpose in life is to fall in love they mate and shortly after they die and then their purpose in life is to give food to other insects and animals Bobcats lizards road runners are their main predatory dangers but they scare me to death one of them pinned me in my kitchen once it got in the house and I didn’t have my shoes on I was scared stiff I screamed for someone to come help me like a little girl with a skinned knee

  9. What the Heck!

    @ dznutz

    I too live in Spokane Valley and just found a dead one upside in my flower bed! We do not have a bug problem so does anyone know why they would be migrating so far north?

  10. @What the Heck!

    Yea doesnt make sense why we are getting them up here since we have nothing in the NW area that they live on/eat (the tree)…… I just want to know if they are poisonius to humans LOL!!

  11. We bought this house in North Phoenix 2.5 years ago. About 1.5 years ago we dug up an old Palo Verde tree that was dead & dug up all the grubs that were there. The first year here we did see some Palo Verde beetles in the air at night but this year we’ve seen a lot more. I have now found what appear to be Palo Verde grubs in both my garage & on the floor of my hallway closet. I’ve found these things in a folded cardboard box in my garage, under cardboard boxes that I had set down just over night, and today I found another one on the floor of my hallway closet, there was a liquid red, like blood, leading under the closet door. We had quite a storm 3 days ago, we have an area just inside the garage where water puddles, today I noticed after the water had evaporated that there are 5 of these things dried up where the water used to be. I’m trying to research if what I’m finding are in-fact Palo Verde grubs or something else. Anyone ever heard of Palo Verde grubs coming out & finding their way indoors?

    1. No but my Mom found them in the roots of her pepper tree in October about 5 years back, of course that was found after the tree had died. It seems this year I have not seen any palo verde beetles in the last 4 days. Do you think that they died off earlier this year?

Leave a Reply