Scientific name: Biston betularia
May to August. A common but rarely seen moth with variations in colour depending on the area where they are found – a favourite of genetic studies.
The usual form in rural areas is all white peppered with black dots on both the wings and body. Black forms known as f. carbonaria were once dominant in industrial areas with high levels of pollution although their frequency has been steadily declining in recent years. Intermediate forms known collectively as f. insularia are variable between the light and dark forms.
The larvae can be seen between early July and late September before they overwinter as pupae just below the ground.
Size and Family
- Family – Thorns, beauties, umbers and allies (Geometridae)
- Large Sized
- Wingspan Range – 44-56mm
- UK BAP: Not listed
Caterpillar Food Plants
A wide range of trees, shrubs and smaller plants including Blackthorn (Prunus spinosa), Hawthorn (Crataegus monogyna), Downy (Betula pubescens) and Silver Birch (Betula pendula), limes, sallows, poplars, oaks, Sweet Chestnut (Castanae sativa), Beech (Fagus sylvatica), Bramble (Rubus fruiticosus), Broom (Cytisus scoparius), Black Currant (Ribes nigrum) and Hop (Humulus lupulus).
Woodland, scrub, hedgerows, parks and gardens.
- Countries – England, Wales, Scotland and Ireland
- Very well distributed and fairly frequent throughout most of England, Wales, and lowland Scotland. Also Frequent on the Isle of Man, Ireland and the Channel Islands.