Insects - Pests of Ornamental Trees, Shrubs and Flowers - page 324

Acronicta megacephala (Denis & Schiffermüller)
( 862-863 )
Poplar grey moth
This species occurs mainly on black poplar ( Populus
nigra ), but also attacks other kinds of poplar as well as
pussy willow ( Salix caprea ). The larvae are often found
on such trees in urban areas. Adults occur from May to
July, eggs being deposited singly on the leaves of host
plants. The larvae feed from July to September, and
typically rest on the leaves during the daytime with the
head turned back alongside the abdomen. Fully grown
larvae ( c . 35 mm long) are black, finely speckled with
yellowish grey, and marked with orange or reddish
spots; there is a large pale patch on the seventh
abdominal segment; the body is also partly clothed in
long, fine hairs which arise in tufts from lateral pairs of
brownish verrucae. The moths (40 mm wingspan) are
mainly grey.

Acronicta rumicis (Linnaeus) ( 864-865 )
Knotgrass moth
A generally distributed and common species, the larvae
feeding on various plants from July onwards. The larvae
occasionally damage the foliage of bedding plants and
other cultivated hosts but attacks are of minor
importance. Individuals overwinter as pupae in
subterranean cocoons, and adults emerge in May or
June; in favourable areas there is also an autumn
generation. Fully grown larvae ( c . 35 mm long) are
brownish grey to black, with red markings and two
lateral series of white patches along the back, and lateral
tufts of light, brownish hairs; the subspiracular line is
creamy white, interrupted by raised red verrucae; the
first and eighth abdominal segments are mainly black
and slightly humped; the head is black. Adults (38 mm
wingspan) are mainly blackish to blackish grey; the fore
wings are variably marked with grey and each has a
more or less distinct paler subcostal spot; the hind wings
are light brown.

863

862

862 Young larva of poplar grey moth ( Acronicta megacephala ). 863 Poplar grey moth ( Acronicta megacephala ).

864

865

864 Larva of knotgrass moth ( Acronicta rumicis ). 865 Knotgrass moth ( Acronicta rumicis ).