I was surprised and apprehensive to see this big black wasp on a milkweed flower near the pond. It was alarming because of its size (over one inch) but is not a pest to harm people. This Great Black Wasp Sphex pennsylvanicus, looks iridescent violet-black with smoky transparent wings that have a violet sheen. They visit flowers to feed on nectar and pollen; no harm to the plants.
The female Black Wasp digs a burrow in the ground to reproduce her kind. She hunts katydids, paralyzes them, and places several in the burrow. She then lays eggs in the burrow. They hatch into larvae. They have a ready meal, quietly growing into adult Black Wasps.