Pacific Pests, Pathogens and Weeds - Online edition

Pacific Pests, Pathogens, Weeds & Pesticides

Citrus fluted scale (343)

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  • Worldwide distribution. On many woody plants, trees, ornamentals and weeds. Important, potentially devastating on citrus.
  • Damage: (i) sucks sap, leaves wilt, stems dry, and shoots dieback, (ii) honeydew drips onto foliage which is blackened by sooty moulds.
  • Adult (females) up to 7 mm long, covered in yellow or white wax, with orange-red, yellow, brown body. They are hermaphrodites; fertilised eggs kept in fluted egg sac. Males winged, and rare.
  • Spread by 'crawlers' (nymphs) walking, or carried by wind, vehicles, animals, birds, on clothes, and the trade in plants.
  • Natural enemies: predators, e.g., ladybird beetle, Rodolia cardinalis, and fly parasitoid (Cryptochaetum).
  • Cultural control: nursery stock free from scale; if present, prune and spray (see below); in field, provide adequate nutrition.
  • Chemical control: spot-spray infestations with soap solution, horticultural or white oils (see Fact Sheet no. 56); avoid malathion and synthetic pyrethroids - they will kill natural enemies. Use pyrethroids against ants.
Common Name

Citrus fluted scale, cottony cushion scale,

Scientific Name

Icerya purchasi

AUTHOR Grahame Jackson
1Information from Swaine G (1971) Agricultural Zoology in Fiji. Her Majesty's Stationery Office. London; and CABI (2016) Icerya purchasi (cottony cushion scale). Crop Protection Compendium. (; and Icerya purchasi. Wikipedia. (; and Icerya purchasi Maskell. Featured Creatures, Entomology & Nematology. UF/IFAS, University of Florida. (; and from Weeks JA (2012) Citrus Pests Cottony cushion scale Icerya purchasi (Hemiptera: Margarodidae). USDA, University of Florida. (; Photos 1&5 Jeffrey W. Lotz, Florida Department of Agriculture and Consumer Services, Photo 2 Lesley Ingram, Photo 3 Lorraine Graney, Bartlett Tree Experts, Photo 4 Sonya Broughton, Department of Agriculture & Food Western Australia,

Produced with support from the Australian Centre for International Agricultural Research under project PC/2010/090: Strengthening integrated crop management research in the Pacific Islands in support of sustainable intensification of high-value crop production, implemented by the University of Queensland and the Secretariat of the Pacific Community.

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