Available products to use in MD for CrepeMyrtle Barkscale - Ask Extension
Hello - we have crepe myrtles in Ocean Pines MD in Worcester county and I cannot find appropriate insecticides for removing crepe myrtle bark scale. E...
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Available products to use in MD for CrepeMyrtle Barkscale #924955
Asked February 23, 2026, 4:31 PM EST
Hello - we have crepe myrtles in Ocean Pines MD in Worcester county and I cannot find appropriate insecticides for removing crepe myrtle bark scale. Each of the products recommended are not available in MD.
Is there a recommended consumer project that is available for use?
Worcester County Maryland
Expert Response
Insecticide options for controlling scale fall into three general categories: topical, which primarily affect crawlers (the "hatchling stage" and overwintering individuals; insect growth regulators (IGRs) that disrupt maturation and reproduction; and systemic, which are absorbed by the plant and ingested by the scale as they feed. You may have been looking for a systemic in the neonicotinoid category (active ingredients like imidacloprid and dinotefuran), which are regulated in Maryland and only legal for certified pesticide applicators to buy and apply (if being used on outdoor plants). A hired landscaper or arborist who has such a license (most do) can apply those pesticides, or they may have better spray or injection equipment to apply one of the other pesticide options, especially if the crapemyrtle is large and mature.
If you want to spray the plant yourself, you may be limited in practicality to horticultural oil, used either as a "summer rate" to target crawlers when they appear, and/or as a "dormant rate" to target overwintering scale. They are the same ingredient, just used at different concentrations, and the product label will describe how to use them. You can also learn more on the linked web page about horticultural oil.
Since crawlers are the only life stage that is highly vulnerable to a topical spray like hort. oil, you'd need to monitor the scale closely to determine when to make applications. Crapemyrtle Bark Scale have more than one generation per year, and generations can also overlap or have extended crawler periods (several weeks long each), which makes management of this scale species particularly difficult. A hired professional with experience treating this scale would be valuable in that case, if that's an option.
Extension isn't able to keep a database of all the products on the market that are labeled for the control of particular pests, nor do we recommend specific products/brands or suppliers, but there are fortunately many options at area garden centers (and possibly hardware stores) for horticultural oil formulations. IGRs tend to be specialty chemicals that only pesticide-focused companies or mail-order garden pest control companies may stock, and while a couple other systemic ingredients may be available locally at retailers, they won't always work well on scale insects depending on the method of application (for example, a foliar spray won't help much with a bark scale) and the active ingredient.
Miri
If you want to spray the plant yourself, you may be limited in practicality to horticultural oil, used either as a "summer rate" to target crawlers when they appear, and/or as a "dormant rate" to target overwintering scale. They are the same ingredient, just used at different concentrations, and the product label will describe how to use them. You can also learn more on the linked web page about horticultural oil.
Since crawlers are the only life stage that is highly vulnerable to a topical spray like hort. oil, you'd need to monitor the scale closely to determine when to make applications. Crapemyrtle Bark Scale have more than one generation per year, and generations can also overlap or have extended crawler periods (several weeks long each), which makes management of this scale species particularly difficult. A hired professional with experience treating this scale would be valuable in that case, if that's an option.
Extension isn't able to keep a database of all the products on the market that are labeled for the control of particular pests, nor do we recommend specific products/brands or suppliers, but there are fortunately many options at area garden centers (and possibly hardware stores) for horticultural oil formulations. IGRs tend to be specialty chemicals that only pesticide-focused companies or mail-order garden pest control companies may stock, and while a couple other systemic ingredients may be available locally at retailers, they won't always work well on scale insects depending on the method of application (for example, a foliar spray won't help much with a bark scale) and the active ingredient.
Miri
