The wings are a dull green colour with a gold leading forewing edge and two fairly straight, white cross-lines. Similar to Little Emerald but a stronger green in colour.

The adults fly at night from dusk and are attracted to light. The caterpillars can be found from July to August before overwintering as pupae suspended by threads from the foodplant or in leaf litter.

Size and Family

  • Family – Emeralds (Geometridae)
  • Small Sized
  • Wingspan Range – 22-26mm

Conservation Status

  • UK BAP: Not Listed
  • Scarce (Nationally Scarce A)

Caterpillar Food Plants

Woody plants including Heather (Calluna vulgaris), Cross-leaved Heath (Erica tetralix), birches, Creeping Willow (Salix repens) and Gorse (Ulex europaeus)


Damp heaths and mosses


  • Countries – England
  • Nationally Scarce A. Found locally in Cornwall, Devon, Somerset, south-east Dorset, Hampshire, Surrey and Sussex along with one site in Cumbria. Previously recorded in Wiltshire, Gloucestershire and Worcestershire.
Small Grass Emerald - Garry Barlow

Small Grass Emerald

Small Grass Emerald - Patrick Clement

Small Grass Emerald

Small Grass Emerald - Tamás Nestor

Small Grass Emerald

Small Grass Emerald (caterpillar)

Small Grass Emerald (caterpillar)