These gorgeous beetles, in the Cerambycidae family (long-horned beetles) are very common right now, almost always on goldenrod. Their larvae feed inside black locust trees (of which we have many in the ravine), but the adults are nectar feeders, as here. Soon, the adults will lay eggs on the locust trees, the larvae will overwinter under the bark, eventually pupate in the following summer, and then we get to see the adults in late summer and early fall.