Pest: Wax scale (Ceroplastes spp.)
Pest Type: Insect Pest
Major Identifying Features: Scale insects feed by sucking plant juices and some inject toxic salvia into plants, scales look different than other insects, females are circular to oval, wingless, and lack separate head or other recognizable body parts, are hemispherical and covered with thick, oily wax, are pale gray, males are tiny, delicate, white to yellow with one pair of wings and antennae, females can reproduce without mating, wax scale can create a gooey mess
Life Cycle: Complete metamorphosis, 4 stages (egg, larva, pupa, adult), eggs are produced beneath the body or cover of the female, nymphs walk along branches or spread with the wind, nymphs are yellow to orange and the size of a period, once they start feeding, they remain immobile for the rest of their lives, one generation per year
Pest Rating: Minor to moderate
Management Rating: Easy to moderate
Host/Season/Outbreak Information: Warm temperatures usually favour scale outbreaks and honeydew protecting ants are around, can be found on Australian willow, Escallonia, mayten, California bay, coyote brush, holly, Mahonia, pepper tree, gardenia
Damage Information: Wax scales rarely threaten plant health, when numerous, some species can weaken a plant and cause it to grow slowly, infested plants appear water-stressed, leaves can turn yellow, and may drop prematurely, plants infested by soft scales and certain other species become sticky from honeydew and may blacken due to sooty mold growth
Management Options: Prevention and monitoring with sticky traps, controlling dust, cultural control with appropriate plant selection, biological control with predatory bugs, beetles, and lacewings (Chilocorus, Hyperaspis, Rhyzobius), parasitic wasps, chemical applications with horticultural oils in spring or summer
Sources:
Pests of Landscape Trees and Shrubs (Book)
