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”



23 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!

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