Insects - Pests of Ornamental Trees, Shrubs and Flowers - page 81

gardens are also affected. The aphids, which excrete
considerable quantities of honeydew, feed on the
foliage, shoots and branches. They cause discoloration
and die-back of affected tissue, which reduces plant
vigour. The aphids occur from May onwards, although
often in only small numbers. Winged forms, which
spread infestations, are reared from June to August.
Adults (1.8-3.9 mm long) are mainly orange brown to
yellowish brown, with blackish markings diverging
back from the thoracic region, light grey transverse
stripes on the abdomen and a black band between the
prominent black siphuncular cones; the rostrum is
relatively short ( c . 1 mm long). The pest is widely
distributed in Europe, particularly in southern areas; in
Britain attacks are most often reported in the south and
west of England.

the late autumn or early winter when oviparous forms
finally deposit the overwintering eggs. These eggs
( c . 1.6 mm long) are black and shiny, and are laid in
rows along the needles. They hatch in the spring.
Colonies of pale aphids then develop on the shoots,
individuals clustering together on the wood between the
bases of the needles. Breeding continues throughout the
summer, including the production of winged forms;
later-produced individuals tend to be darker in colour
than the spring forms. Colonies are relatively small but
produce considerable quantities of honeydew. Although
damage to established trees is slight, attacks on nursery
trees may cause considerable damage, leading to
discoloration of the needles, premature loss of needles
and reduced plant vigour.

Cinara fresai (Blanchard) ( 162-164 )
American juniper aphid
Dense colonies of this large (2.2-4.2 mm long), dark
brownish-grey species occur locally on juniper
( Juniperus ) in southern England from June onwards.
This species is readily distinguished from Cinara
juniperi (see below) by the two broken, divergent black
stripes which extend back from the head. The aphids
infest the foliage and stems of various ornamental
junipers (including J. chinensis, J. sabina, J. squamata
and J. virginiana ), protected by earthen shelters
constructed by ants. Infestations lead to the
development of sooty moulds and noticeable blackening
of shoots, affecting the appearance and hence quality of
plants. Attacks also cause die-back of shoots and,
sometimes, death of trees.

165

Cinara juniperi (Degeer)
Juniper aphid
A widely distributed species on juniper ( Juniperus ),
primarily common juniper ( J. communis ). The aphids
are pinkish brown, slightly smaller (2.2-3.4 mm long)
than Cinara fresai , and have a relatively short rostrum.
Also, unlike Cinara fresai , infestations are usually
restricted to the young, green shoots and needles. Sooty
moulds develop on honeydew excreted by the aphids,
and this disfigures established ornamentals and nursery
stock.

165 Eggs of large pine aphid ( Cinara pinea ).

166

Cinara pinea (Mordwilko) ( 165-166 )
Large pine aphid
This common, widely distributed, large-bodied
(3.1-5.2 mm long) aphid feeds on Scots pine ( Pinus
sylvestris ), infesting young shoots bearing new or one-
year-old needles. Adults vary from grey to orange-
brown or dark brown, and are present from the spring to

166 Colony of large pine aphid ( Cinara pinea ) on
Pinus .