They seem to be everywhere! While addressing them on a large scale is very difficult, you may have some luck with protecting a small grouping of trees.

Spotted lanternflies were a menace in Pennsylvania before they got to New York and much of our protocol comes from that state. Penn State's College of Agriculture recommends using sticky bands around the trunks of your trees. Both adults and nymphs get stuck on these traps as they crawl up the trees. This is a non-chemical approach but it can affect unintended and beneficial insects as well so use a relatively narrow band (< 5 inches) to reduce the unintended capture. Commercial products are available and retain their stickiness longer than DIYing with duct tape. Keep the tape tight to the tree and encircle the full circumference or the lanternflies will dodge the trap.

A full article on the technique from Penn State can be found here and includes information on modifications to increase protection from sticky traps to birds and animals.

Courtesy of NYBG Plant Information Service