ENTFACT Supplement: Scale Insects In Kentucky

by Lee Townsend, Extension Entomologist
University of Kentuky College of Agriculture

Cottony Maple Scale (ENTFACT-427)
Host: maples, other woody plants
Appearance: flat, oval, brown, 1/8 inch long with large white cottony egg sac protruding from under body
Crawlers Active in Kentucky: June and July

Euonymous Scale (ENTFACT-428)
Host: Euonymus spp., Pachysandra, Bittersweet
Appearance: females: dark brown or gray, 1/16 inch long, resemble oystershell scales, pear-shaped; males: smaller, narrow, white.
Crawlers Active in Kentucky: First brood: late May; Second and third broods: late July to early September

Juniper Scale (ENTFACT-429)
Host: Juniper, Arborvitae
Appearance: female: circular, flat, dirty white, 1/20 inch, yellow exuviae off-center (looks like a fried egg); males:smaller, narrow, exuviae located at end of shell
Crawlers Active in Kentucky: mid-May

Lecanium Scales (ENTFACT-430)
Host: Arborvitae, Sweetgum, Zelkova, other hosts
Appearance: mostly hemispherical or turtle-shaped, brown, 1/8 to 1/6 inch.
Crawlers Active in Kentucky: varies with species

Magnolia Scale (ENTFACT-431)
Host: Magnolia, Tuliptree
Appearance: broadly oval, convex, 1/2 inch long
Crawlers Active in Kentucky: early September

Obscure Scale (ENTFACT-432)
Host: Pin Oaks, Hickory, Walnut
Appearance: roughly circular, flat, 1/8 inch, exuviae form a central spot surrounded by a gray ring
Crawlers Active in Kentucky: June through August; late July is best time for a single treatment

Oystershell Scale (ENTFACT-433)
Host: Lilac, Maple, Willow, other hosts
Appearance: oyster-shaped, gray, 1/8 inch, exuviae accumulated at narrow end
Crawlers Active in Kentucky: early May when hawthorn blooms

Taxus Mealybug (ENTFACT-434)
Host: Taxus, (apple, cedar, linden, maple)
Appearance: adult mealybug is approx. 8 mm long, they cluster in crotches of twigs and branches; white-gray in color
Crawlers Active in Kentucky: latter half of May, summer

Tuliptree Scale (ENTFACT-435)
Host: Tuliptree, Walnut, other plants
Appearance: hemispherical, 1/3 inch
Crawlers Active in Kentucky: late August

Walnut Scale (ENTFACT-436)
Host: wide variety of deciduous trees and shrubs, rarely on conifers
Appearance: nearly circular, flat, gray with a reddish-brown spot
Crawlers Active in Kentucky: lmid-June, late August to early September