Friday, April 17, 2009

Landscape - Scale Insects: Indian Wax Scale

This is the 15th in a series on scale insects in the landscape. This post is on the Indian Wax Scale. Information is from the University of Maryland.

Indian Wax Scale (Ceroplastes ceriferus), Family Coccidae

Plants Damaged: This soft scale feeds on Chinese and Japanese hollies, azaleas, pyracantha, euonymus, boxwood, flowering quince, camellia, pear, azalea, persimmon, plum, barberry, and magnolia.

Damage Symptoms: This scale is large enough that its mere appearance is aesthetically unpleasing. Heavy populations can cause dieback of the infested plant.

Life Cycle: Females overwinter and eggs are laid in May in Maryland. Crawlers are active in early June. When crawlers emerge they will be yellow to pink in color and will excrete white wax that gives the scale a “cameo” appearance.

Monitoring: The adult females are red and covered with bright white gummy wax. Look for the large, very noticeable females overwintering on the stems.

Control: Horticultural oil does not work well on this scale. Distance applied when crawlers are present works well. Imidacloprid can also be applied as a soil drench in April. It takes 30 - 60 days for uptake into the stems of the plant. Soil application of dinotefuran (Safari) is uptaken in 2 – 3 weeks and should give good control.

Information from "Scales Commonly Encountered in Maryland Landscapes and Nurseries" by Stanton Gill, Extension Specialist in IPM for Nurseries and Greenhouses,and Suzanne Klick and Shannon Wadkins, Technicians, Central Maryland Research and Education Center University of Maryland Cooperative Extension.

No comments: