Mountain Ash Sawfly vs Large Square-headed Wasp
Side-by-side species comparison
| Attribute | Mountain Ash Sawfly | Large Square-headed Wasp |
|---|---|---|
| Scientific Name | Pristiphora geniculata | Ectemnius cephalotes |
| Order | Hymenoptera | Hymenoptera |
| Family | Tenthredinidae | Crabronidae |
| Size | 5-7 mm | 12-18 mm |
| Habitat | Mountains | Woodlands |
| Diet | Herbivores | Wood Feeders |
| Regions | Europe, introduced to North America | Europe |
| Conservation | Least Concern | Least Concern |
Mountain Ash Sawfly
A small blackish sawfly with pale legs whose green larvae can completely defoliate mountain ash (rowan) trees. Larvae have dark heads and feed gregariously.
Did You Know?
Introduced to North America in the early 1900s, it quickly became the most damaging pest of ornamental mountain ash trees across the continent.
Large Square-headed Wasp
A large solitary wasp that nests in dead wood and provisions its nest with captured flies. Has a distinctively large, square-shaped head. Common in gardens and woodland.
Did You Know?
Nests in old beetle holes in dead wood, stocking each cell with paralyzed flies for its developing larvae.