Crapemyrtle Bark Scale is treated the same as other scale, just the timing of any pesticide applied will depend on the crawler period. (Crawlers are the newly-hatched juvenile scale that are the most vulnerable life stage to pesticide intervention.) Since this is still a relatively new scale for the Maryland area, we are still learning about when to expect a crawler period for each generation. So far, they appear to have at least two full generations per year in our area, so there will be at least two crawler periods. Once we have more specific data, we'll update the page linked above with life cycle details.

A certified pesticide applicator can be hired to apply either a systemic (plant-absorbed) product, an insect growth regulator (IGR), or topical insecticide sprays like horticultural oil. Someone experienced with managing scale insects should be able to monitor the Crapemyrtle Bark Scale for you in order to look for indications of crawler activity, since the process is the same for all scale species.

A heavy scale outbreak might take more than a full year to suppress. Dead scale do not necessarily fall off the bark right away, so it's possible a treatment will be starting to work but the tree might not look any different at first, since the white waxy scale covers will remain stuck to the bark for a while.

Miri

I check the page for updates on when to expect crawlers, nothing yet?  Have you any information?  I’ve read where Sevin knocked down so many predators that the scale population increased when using that.  What pesticides are suggested?

Thank you. 

We do not update the Crapemyrtle Bark Scale web page each time a crawler generation emerges, as that will change every year and every season with the nuances of the weather. Plus, data is still being collected to determine when crawlers are expected for this relatively new pest species, and several years of data will be needed to determine an average crawler emergence date for each generation. Last year, as an example, crawler emergence peaked around early to mid-June and again in late August through early September, with a tertiary peak in early October.

As noted in the page, the management section of our general scale insect information page contains options for pesticide use when it is warranted. Horticultural oil is a low-toxicity choice that is a good start, either as a "summer rate" dilution for growing season sprays or a "dormant oil" rate for winter. You are correct that we would not recommend Sevin, as it has harsher impacts on beneficial insects.

Miri