Horticultural Development Company
Skip to Content Skip to HDC Navigation Skip to Apple Best Practice Navigation

Woolly aphid (Eriosoma lanigerum (Hausmann))

Woolly aphid

Woolly aphid colony with wax blown away

Woolly aphid is a sporadic pest of apple, which is sometimes present at low levels in orchards but only increases to cause problems in some years. Damage is expected to occur in years after warm winters when aphid colonies increase in early summer and spread onto extension growth. The entire life cycle is passed on the host tree.

Earwigs, ladybirds and the parasitic wasp Aphelinus mali are important natural enemies of woolly aphid and usually regulate populations to below damaging levels.

Artificial refuges should be provided for earwigs in orchards where woolly aphid is a problem and the use of pesticides harmful to earwigs and other natural enemies should be avoided.

The aphid itself is brown to greyish purple but is easily recognised as it produces conspicuous secretions of white woolly wax.

Orchards should be inspected  for the pest (i.e. for the colonies that produce conspicuous masses of white woolly wax) at the end of blossom, in June and again in mid-summer.

The June assessment is critical. At least 25 trees per orchard should be inspected. If one or more trees in the sample has woolly aphid, in the extension growth, treatment with an insecticide is justified.

Control  

  • Chlorpyrifos (various products.), flonicamid (Mainman, Teppeki), nicotine (various products) and thiamethoxam (Centric) are specifically recommended for control of woolly aphid on apple.
  • Pirimicarb (Aphox etc.) can also give good control if applied in higher spray volumes in warmer weather conditions.
  • Flonicamid (Mainman, Teppeki) or pirimicarb (Aphox etc) are good choices because they are selective, have low toxicity to natural enemies and are partially systemic.
  • Chlorpyrifos (Dursban etc.) is also effective. Sprays of chlorpyrifos (various products), often applied for other pests, have an important benefit of suppressing woolly aphid in conventional orchards.  
  • Use of synthetic pyrethroids, which are harmful to natural enemies, should be avoided.  
  • Thiacloprid (Calypso) has little or no effect on woolly aphid. Calypso may possibly be harmful to earwigs, the most important natural enemy of woolly aphid. If this is the case, sprays of thiacloprid (Calypso) in mid- and late summer when earwigs are present in the tree, could cause later outbreaks of woolly aphid.
  • Higher volume sprays are likely to give best results.

 

Insecticides approved for use on apple which are recommended to control woolly aphid or offer some incidental control when applied to control other pests

Thiacloprid (Calypso) is not listed here because although it is effective against other aphid species on apple and many other pests, it is ineffective against woolly aphid

Choice of insecticides - efficacy factors

Active ingredient

Trade name (examples)

Class

Selectivity

Approved for control of -

Safety to Typhs

 

acetamiprid

Gazelle

neonicotinoid

broad-spectrum, systemic

 Aphids and Whitefly

safe

chlorpyrifos

Dursban etc.

organo-

phosphate

broad spectrum

Aphids including woolly aphid, caterpillars,

sawfly, capsids etc.

safe

cypermethrin

various

pyrethroid

broad spectrum

Aphids, capsids,

caterpillars, codling & tortrix moths, sawflies, apple sucker

harmful

deltamethrin

Decis etc.

pyrethroid

broad spectrum

Aphids, codling & tortrix moths

harmful

dodecylphenol ethoxylate

Agri 50E

physical acting insecticide

broad spectrum

Aphids, leafhoppers, mealy bugs, spider mites

harmful

fatty acids

Savona

soap

broad

spectrum

Aphids, scale insects

harmful

flonicamid

Teppeki, Mainman

neonicotinoid

selective

Aphids and woolly aphid

safe

maltodextrin

Majestik

polysaccharide

broad spectrum

Aphids, spider mites

harmful

pirimicarb

Aphox etc.

carbamate

selective aphicide, trans-laminar

Aphids

safe

pyrethrins

Spruzit

extract from pyrethrum

broad spectrum

Aphids, apple blossom weevil, caterpiallars, spider mites

harmful

Choice of insecticides - Safety factors

 

Hazards

Harvest interval

(days)

 

Max. no. sprays

Buffer zone

Width (m)

 

Anticholin-

Esterase?

 Humans

Fish &

 aquatic life

Bees

acetamiprid

no

u

h

u

14

2

20

chlorpyrifos

yes

h, i

ed

ed

14

3

18

cypermethrin

no

h, i

ed

d

0

5

18

deltamethrin

no

h, i

ed

d

0

u

18

dodecylphenol ethoxylate

no

u

u

u

0

u

u

fatty acids

no

u

h

u

0

u

sm

flonicamid

no

u

h

u

21

3

sm

maltodextrin

no

i

d

d

0

20

sm

pirimicarb

yes

t, c

h

-

3

u

sm

pyrethrins

no

h,i

ed

d

0

4

50

h=harmful, i=irritant, d=dangerous, ed=extremely dangerous, t=toxic, c=closed cab required for air assisted sprayers, sm=statutory minimum of 5 m for broadcast airassisted sprayers u=uncategorised/unclassified/unspecified

* approval for use and storage of all products containing nicotine is allowed only until 08 June 2010

 

Control in organic orchards

In organic orchards where the pest is often troublesome, emphasis should be placed on cultural control measures such as the provision of artificial refuges for earwigs and, if practicable, physical destruction of colonies in spring.

  • High volume sprays of fatty acids (potassium soap) (Savona) should be applied when damaging infestations develop.

 

 Further reading

 



smallest type size medium type size large type size