How to Kill Bark Scale on Crape Myrtles

July 17, 2016

We Texans sure do love our crape myrtles, unfortunately so does this fairly new pest to North Texas called bark scale. Do not fear though, as it’s easy to treat. Crape myrtles are a very hardy trees with lots of reserves, so it would take several seasons of bark scale for the tree to succumb to this pest. Bark scale originates from China and was brought to the U.S. in 2010. A&M has identified this pest as Eriococcus lagerstroemiae, and suspects that it was brought into the U.S. on a crape myrtle plant.

Bark scale on crape myrtle branch
Bark Scale along the branch of a Crape Myrtle

Many people who call us describe their trees as covered in white dots, or white cotton like bumps. They often think the white dots are a fungus, but it is in fact a bug. If you smash one when it’s alive it will actually ooze a reddish-pink liquid. You will oftentime see black sooty mold in addition to the white bark scale. Black sooty mold literally looks like black dust on your leaves and bark. The scale sucks the sap from your branches and tree trunks and then the sugars and yeast in the sap attracts the mold. They go hand in hand, but black sooty mold is really just a cosmetic issue. Treatment for the black sooty mold is not recommended and once the scale is terminated then the black sooty mold will disappear as well.

To kill the scale we recommend Bayer Advanced Tree and Shrub Protect and Feed Concentrate. It comes in granular and liquid form, and provides 12-month long-lasting systemic protection against the scale. The application rate depends on the tree trunk size, so you will just need to measure around the tree trunk and then pour the appropriate portion of granules or liquid around the base of the tree. Please read Bayer’s label for application rates needed for your tree, and for additional information. This product is readily available online and at most local home & garden stores such as Lowes and Home Depot.

Kill scale with Bayer Advanced Tree & Shrub Protect & Feed
Bayer Advanced Tree & Shrub Protect & Feed

I do want to mention that we are in no way paid or sponsored by Bayer. Over the years we have just found their products to be the perfect fit for our customers needs. Generic brands might be available, but just make sure they contain Merit. The best time of year to treat is between May-July when the scale are most active. After the scale has died you will just see a white shell as shown in the pictures above and you will not be able to see any pink coming from the scale once smashed. The white shells often take a while to fall off but you can gently brush them off to make the tree cosmetically more attractive.

Tuscarora Crape Myrtle Flower
Flower Cluster from a Tuscarora Crape Myrtle

Crape myrtles are still a tree that we highly recommend for North Texas as they are adaptable to a wide range of soil types, heat tolerant, and drought tolerant. Occasional pests here and there are going to happen to all trees as some point, but this is super easy to treat. Crape myrtles are also know for their resistance to powdery mildew, and can thrive in the sun and part shade.

I hope you have found this information helpful. I will be sharing more information and treatment plans for other common North Texas pests as they come about. The scale pictures were taken by my talented photog friend, Lauren.

-Denise



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We Texans sure do love our crape myrtles, unfortunately so does this fairly new pest to North Texas called bark scale. Do not fear though, as it’s easy to treat. Crape myrtles are a very hardy trees with lots of reserves, so it would take several seasons of bark scale for the tree to succumb to this pest. Bark … Continue reading “How to Kill Bark Scale on Crape Myrtles”



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We Texans sure do love our crape myrtles, unfortunately so does this fairly new pest to North Texas called bark scale. Do not fear though, as it’s easy to treat. Crape myrtles are a very hardy trees with lots of reserves, so it would take several seasons of bark scale for the tree to succumb to this pest. Bark … Continue reading “How to Kill Bark Scale on Crape Myrtles”



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We Texans sure do love our crape myrtles, unfortunately so does this fairly new pest to North Texas called bark scale. Do not fear though, as it’s easy to treat. Crape myrtles are a very hardy trees with lots of reserves, so it would take several seasons of bark scale for the tree to succumb to this pest. Bark … Continue reading “How to Kill Bark Scale on Crape Myrtles”



31 thoughts on “How to Kill Bark Scale on Crape Myrtles”

  1. I’ve learned a lot via Google search regarding the Cotton White and black bark growth on my trees.

    First site I’ve come across that explains in layman terms on how to kill an save my trees.

  2. Another question then, we planted many photinia shrubs in our backyard, along our fence. We know that there’s a fungus or disease that is common to it, that can kill them. We lost about 5 shrubs to that illness, shortly after planting them. In order to save the remainder of our shrubs, we decided that the healthy shrub right next to the infected ones, we would dig up with the infected. We were able to save the rest of the shrubs by doing this. My question is, if this happens again, is there a preventative or can we treat them in an attempt to save them, or is it best to do what we did before? Of course I would prefer to save them if possible. I am what people would call a black thumb. My friends call me the plant serial killer. I don’t have a talent for these things. As a matter of fact, it’s quite the opposite, I seem to just kill any plant given to me; even following written instructions. I love plants. Having been raised in Germany where there is lots of vegetation.

    So glad & thankful to have found this article! It has great & simple info on how to identify and treat scales on our crepe myrtles. Not only was the information great; but, as others have stated, your instructions on how & when to treat, as well as describing the issue(s) in layman terms, made it easy for us non-horticulturalists / non-botanists /non-arborists to understand. I was glad to find out that we could save them!

    1. Hi Nicki, Thanks for your kind words about our blog. Yes with the Red Tip Photenias you likely have Entomosporium leaf spot. Their is no cure for this disease no matter what blogs you find on the internt. Howard Garrett probably has some oil treatment or something wild, but please don’t waste your money on such things. Thier is no cure and the infected plants must be destroyed and removed immeditely to hopefully stop the spread to others. Pickup all of the leafs on the ground as well and throw them away too. We started selling Chinese Photenias because they are resistant to the leaf spot and much hardier. The Chinese Photenia is actually a parent plant to the Red Tip Photenia. Hope this helps you and good luck!

    1. Hi Cindy, thanks for your comment. Yes, the black sooty mold will fade off the back over time. It is a slow process, but the bark will return to its original color down the road. Also be aware that the shell of the bark scale can remain on the bark for a extended amount of time as well. You can try taking a soft bristle brush with water to remove the bark scale and the sooty mold. Best of luck!

        1. Yes you can, and we recommend the Bayer product listed in the article. Really your only organic option is to smash each scale bug individually with some sort of utensil. Spraying the bark with water does not work. The oils do not work. We hate that the insecticides are the best method for this bug, but it’s the unfortunate case.

  3. Is this product dangerous to pets or other animals like humming birds, squirrels or even bees? Thanks!

    1. Hi Robin, thanks for your comment. I would definitely recommend that you contact Bayer with those questions. They will be able to advise you better than I. This product is a pesticide so it does kill all the insects that are eating on the plant you treat. You can always just throw on a pair of gloves and go to town smashing all of the individual scale bugs. I always use chemicals as a last resort.

  4. I would like to knew how using a systemic pesticide will affect all of the bees that nectar on the Crepe Myrtle flowers?

    1. Hi Meg, thanks for your comment. I have the same response for you as Robin. I would definitely recommend that you contact Bayer with those questions. They will be able to advise you better than I. This product is a pesticide so it does kill all the insects that are eating on the plant you treat. You can always just throw on a pair of gloves and go to town smashing all of the individual scale bugs. I always use chemicals as a last resort.

  5. Would this bark scale be the reason my myrtles didn’t bloom much this season? Do you recommend the Bayer spray over washing the bark with soap and water like some sites have recommended?

    1. Thanks for your comment. Several factors can cause Crape Myrtles to not bloom, or bloom far less than others around DFW. One cause is underwatering. Notice how beautiful the Crape Myrtles look around town after a nice rain passes through? Another cause is too much shade. As nearby shade trees grow and mature then the crape myrtles are left hidden underneath and struggle to get enough sunlight. Third cause could be tree stress and shock from pests. Scale and aphids are the biggest nuisances that I see on crape myrtles. As far as treatment goes, we do not feel that the oils, soaps, and washes from other sites work. We of course wish that more organic options really worked, but sadly they do not seem to be effective enough. I would say give them a try if you would like and then you can try the Bayer if all else fails. Bayer will have a 100% success rate on wiping out the scale. Good luck to you and we greatly appreciate you reading out blog. <3 - Denise

  6. Both you and the label says measure the trunk to see how much to use. For crepe myrtles, does this mean measure each trunk and add them together, or measure the overall circumference of the crepe at the base?

  7. I live in north Mississippi and purchased today the Bayer treatment. Is it too late to bother treating or should I leave the scales alone until spring? I realize it’s past optimal treatment time. Thank you.

    1. Hi Parke, thank you for your question. I would go ahead and apply it now. The bugs are still active right now. You can also treat again in the Spring as needed. Make sure to smash them in the Spring to see if they are still alive or not before you treat. Sometimes the shells take a while to fall off, but the bugs are dead. You will see a pinkish red ooze come out when smashed if still alive. Good luck!

  8. Hi All, I treated my crepe Myrtle with Bayer Advance in the beginning of May. For the first time after 10 years, the tree did Not blossom ( no indication of one single flower). Has someone experienced a similar situation? What happened? Will the tree blossom again?

    1. Hi Mary, I am so sorry that I missed this message last month. The crape myrtles here started blooming shortly after you posted this message. Have your crapes bloomed since? – Denise

  9. Hello. Thanks for your advice about white scale. One of my Crepe Myrtles (4′ high, raised from an Audubon sapling) had a heavy dose of white scale, accompanied by ants. I knocked off most of the scale with my hose sprayer, followed by spraying with a product called “Eight.” I then fertilized the plant with a granular product. Now that I’ve discovered your recommendations, how soon before I can apply the Bayer product, please?
    Thanks!

    1. Thanks for writing in Richard. I am not familiar with the product called “Eight” but the Bayer product I recommend can be applied at any time while the tree is not dormant so it’s actually absorbing the product. The ants will disappear later, don’t worry about them. They are just enjoying the sap that is already out on the bark and are not doing any additional damage to the tree. Really just cleaning up the wasted sap. Hope this helps. Reach out with any additional questions. -Denise

  10. Bark scale attacked both our beautiful Crepe Myrtles last year. The entire tree turned black and sappy. I went to several local garden centers, asked questions, showed pictures and nobody had a clue. My husband wanted to cut them down but I insisted we wait it out until the next growing season. I gave them a good pruning.

    Spring came and they still looked terrible. It was hard to watch all the other Myrtles in the neighborhood grow and bloom while ours just stood there all black and sad. It took a while but they did put out new growth. They even bloomed in late July and the Japanese Beatles had a celebration. I was so happy they were doing great.

    Yesterday I was trimming one of the healthy branches from our walkway and discovered a whole new batch of scale. Ugh! Im so disappointed. I know it is late in the season but I’m going to try the recommended product and cross my fingers. They are still in the active growing phase. Do you think one application will suffice? If not, when should I reapply? Will my Crepe Myrtles always have bark scale? Any additional knowledge is much appreciated! Thanks!

    1. I am so sorry to hear that you have such an ordeal with the scale. Scale is easy to treat now that you know what you have. I am actually working on an update to this blog with a more in depth treatment plan since some people see adult scale, while others might just see the larvae and crawlers. For crawlers and larvae, you will need a minimum of 3 applications in a 7-10 day rotation using the Bayer 3-in-1. For mature adults, please apply Bayer Advanced. Bayer Advanced lasts one year and it’s a good preventative. Honestly though, if you just see a few scale on that branch, then I would just smash those. Look in the crotches of the branches too, they love to hide in there.

      To give you tree a boost also apply Dynamite Fertilizer and Superthrive.
      Holler if you have any other questions. We are happy to help.
      -Denise

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