Fortunately, you don't need to take action. The initial advice of kill-on-sight for this insect, initiated by the MD Dept. of Agriculture several years ago, was trying to help slow their spread once they were first discovered in Maryland. Now, most MD counties have some level of Spotted Lanternfly population, and they have already spread outside of the state. Plus, even successful insecticide treatments or trapping is not effective enough to get rid of most of the population, which as you note, will reside out of reach or undetected in tree canopies. Additionally, there is no pesticide used to treat SLF that won't also risk harming other insects.

Miri

Thank you! 

Crapemyrtle are widely overplanted and are now dealing with a new, damaging bark scale insect pest. 

Currently there is disagreement among organizations as to whether they are invasive. For instance the Maryland Biodiversity Project website lists them as non-native but not invasive (they have been found having escaped our gardens in 2 counties), while the Maryland Invasive Species of Concern calls it invasive:
https://mdinvasives.org/iotm/watch-out-for-creepers-on-your-crapemyrtle/#:~:text=Crapemyrtle%20itself%20is%20a%20nonnative,as%20other%20invasive%20tree%20species.
This link also suggests native alternatives to plant instead.


Christine