Extension > Garden > Diagnose a problem > What insect is this? > Garden Pests > Flies, moths, wasps,and other insects with obvious wings - 3/4 inch and larger > Great black wasp
Great black wasp
Sphex pennsylvanicus
Description: 1 to 1 1/4 inch long. Iridescent violet-black with smoky black wings with a violet sheen.
Where/When: Found on a variety of perennials. Adults are active July to September.
Significance: Visits flowers to feed on nectar and does not harm plants. It is alarming because of its size, but is not a pest to people.
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