What's That Bug? does not endorse extermination

red bettle of some sort
Location: portland, tx
April 10, 2011 9:04 pm
Trimming oleanders today and came across these and I don’t know what they are. I live in Portland Texas, its spring time and found them all around. Not to bad though. Thanks for any info.
Signature: chris

Large Milkweed Bug Nymphs on Oleander

Hi Chris,
We are very interested in your letter.  These are Large Milkweed Bug nymphs,
Oncopeltus fasciatus, and as the name implies, they typically feed on Milkweed.  They are Seed Bugs and they feed by sucking the juices from the seeds which also contain the toxic sap.  Many insects that feed upon milkweed, including the Monarch Butterfly, store toxins that are found in the sap of the plant.  The toxins help to protect the insects from predators, and many such insects sport red and black warning colors like these Large Milkweed Bugs.  Oleander has similar qualities and insects that feed on the leaves of Oleander are similarly protected.  This is the first time we have heard of Large Milkweed Bugs being associated with Oleander, but a web search has uncovered an article published in Ecological Entomology entitled Nerium oleander as an alternative host plant for south Florida milkweed bugs, Oncopeltus fasciatus by EDWARD KLAUSNER, ELIZABETH RUTH MILLER, HUGH DINGLE.  Since we do not subscribe to the online Library, we cannot read the entire article, but this abbreviated abstract provides some fascinating information:  “1  Life history data were gathered for south Florida Oncopeltus fasciatus reared from eggs on Nerium oleander seeds and milkweed seeds in the laboratory.  2  Milkweed seeds were found to be a superior food source since O.fasciatus grew faster, laid more clutches, and has a higher total fecundity on milkweed seeds.  3  Fruiting N.oleander was found to be a better food source than nonfruiting milkweeds in a summer field study in south Florida since no nymphs survived to the adult stage on nonfruiting milkweeds but some did on N.oleander.  4  O.fasciatus adults and nymphs are abundant on N.oleander in the summer in south Florida when N.oleander is fruiting; no O.fasciatus nymphs are found in the summer on the milkweeds which are not fruiting.  5  O.fasciatus leave N.oleander in the autumn when milkweeds start to fruit and can then be found on fruiting milkweeds.”

thanks for the response.  My response is “Neat!”.  is there anything else I can provide for you about the plant or insect?

Thanks for the offer Chris, but since both plant and insect are identified, and we found a precedent for the unusual relationship, we cannot think of anything else we would require.  You may always add additional observations as comments to the posting.

Tagged with →  
What's That Bug? does not endorse extermination
Location: Portland, Texas

17 Responses to Immature Large Milkweed Bugs feeding on Oleander

  1. Jeremy says:

    We have had milkweed bugs on our oleanders for years in the high desert in Southern California.

  2. Caroline Deegan says:

    Found a lot of them today on our oleanders in Cave Creek AZ (Sonoran Desert,just north of Phoenix metro area).
    Wonder if they are harmful to the plant–so far ours look OK?
    Caroline

    • bugman says:

      They feed on the juices found in the seeds and seed pods, so they will not harm the parent plant. They will have a negative impact on the production of viable seeds, but that is not an issue with garden oleander.

  3. Jeff says:

    Over the last week or so I’ve been uncovering milkweed type bugs scurring around in the rocks under my oleander trees in Tucson Arizona. I wasnt sure if I needed to attempt to extinguish them or not since last year I did get rid of aphids all over the same oleander trees. Judging by other comments, I will leave them be for now and let nature take its course.

  4. Laurie says:

    I live in southeast FL and have dozens of milkweed bugs infesting my Oleander shrubs. They definitely eat off the pods but are also eating the leaves, leaving my Oleander sparse. Any advice on how to rid my Oleander of the milkweed bug??

    • bugman says:

      We do not provide extermination advice. Milkweed Bugs suck the fluids from plants. They do not chew on leaves.

  5. Laurel Cox says:

    I just found a huge cluster of these milkweed bugs on my Oleanders. I saw a few last year too. My plants are happy, healthy and very pretty.

  6. Angeleen Stapley says:

    I live in Mesa, Az and my Oleanders are covered with these bugs. I have also found that something has been eating on the leaves of my vegetable plants. These are the only bugs I have seen around them. Could they be eating the leaves of my vegetables?

    • bugman says:

      Large Milkweed Bugs have mouths designed to pierce and suck fluids. If your vegetables are showing signs of being chewed, you have a different culprit.

  7. Saundra says:

    My oleander is usually beautiful, however, just recently I have noticed it is not flowering and looks very sad. Upon close inspection, I noticed there are hundreds and hundreds of orange bugs that look exactly like the milk weed bug. I am at a loss as what to do, because I hate killing anything, however, I think I’m going to have to do something, because my tree Oleander is very sick and sad looking:-(

    • Wendy says:

      Same thing here. I’m in Phoenix. Where are you? Literally hundreds!!

      • Saundra says:

        Sorry, I didn’t see this until now, I am in the FL Keys. Unfortunately, we were ground zero during Irma and have barely any vegetation left. Our Oleander survived the 4 ft flood surge and it coming back beautifully, without MW bugs 🐛🤞

  8. Christy Henson says:

    I’m in South Carolina and just planted 5 oleander plants. I have never seen a milk weed bug until now. There are lots of them on my plants.

Leave a Reply

Your email address will not be published. Required fields are marked *