APHIDS
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(Blackfly, Greenfly, Woolly Aphids)
There seems to be an
aphid for every occasion! Also known as 'blackfly', 'greenfly' or
'woolly aphids', they display a wide variation in colour and
appearance.
Aphids overwinter as
eggs on trees and shrubs. In Spring, as the weather warms up, the
eggs hatch into aphids which then produce their own live young, (missing
out the egg stage). Thus vast colonies can build up very
quickly. After several generations of wingless aphids, winged
aphids are produced which can migrate to new host plants. Aphids
feed by sucking out the plant's sap, causing deformed or stunted plant
growth, damaged fruits and flowers, and curled leaves, sometimes with
galls and blisters. Aphids can transmit viruses between plants,
attract ants, and promote the growth of sooty mould.
A crop of greenfly on a
Honeysuckle!
The common Lacewing
Ladybirds, Lacewing
larvae and Braconid parasites do attack aphids, but rarely doing
sufficient damage to aphid numbers to control infestation.
There are many proprietary sprays and 'dusts' on the market; Choose carefully
according to the type of plant, (e.g. edible, ornamental), to be
sprayed, bearing in mind the stage of development of the plant as well
as the aphid! Particular care is required when treating the
Water-lily aphid if there are fish present in the pool or pond.
JV.
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