Is this a sawfly?
This looks like dogwood sawfly larvae. If the shrubs are not too tall, you can pick them off and drop into a bucket of soapy water. You can also hose them off and let the birds eat them once they drop off on the ground.http://extension.umd.edu/hgic/plants/sawflies-trees-and-shrubs
The shrubs should have enough carbohydrates in their root system to put out new growth next season.
See Maryland Biodiversity https://www.marylandbiodiversity.com/viewSpecies.php?species=5080