COTTONY MAPLE LEAF SCALE

Cottony maple leaf scale females are 3 to 4 mm long and 2 to 4 mm wide. They are slightly convex and are brown with a yellow-brown ridge down the back. The body is covered with flakes of clear wax. Their eggs are white to pale yellow and are meshed in a white, cottony ovisac which may be up to 5 mm wide and 12 mm long. Newly hatched nymphs are pale yellow or green and translucent. They closely adhere to the undersides of leaves and are easily overlooked.
In April and May, cottony maple leaf scales crawl to the leaves and lay up
to 2500 eggs in cottony ovisacs on the undersides. These egg-laying scales
do not feed and they soon die. Crawlers hatch in late May to early June
and feed on the underside of the host leaves, usually along the ribs of
the leaf. In late summer, the scales crawl to the twigs where they feed
for the rest of the fall, winter and early spring. In April, male scales
develop into tiny, winged, gnatlike insects which mate with females and
then die. After mating, the females crawl to the leaves to lay eggs. There
is one generation each year.
| Pesticide | (Trade Name) | Formulation |
|---|---|---|
| *acephate | (Orthene) | 9.4% emulsifiable concentrate. |
| *malathion | 25% wettable powder | |
| *soap, insecticidal or Horticultural Oil | (various) | see label |
| bifenthrin | (Talstar) | 10% wettable powder |
| cyfluthrin | (Decathlon) | 20 wettable powder |
| fluvalinate | (Mavrik) | 23% aquaeous flowable |
| carbaryl | (Sevin) | see label |
| buprofezin | (Talus) | IGR, see label |
| *imidacloprid | (Merit) | systemic; see directions |
See the NC Agr. Chemicals manual for additional choices.
* Suitable for home owner use.
Recommendations of specific chemicals are based upon information on the manufacturer's label and performance in a limited number of trials. Because environmental conditions and methods of application by growers may vary widely, performance of the chemical will not always conform to the safety and pest control standards indicated by experimental data.Recommendations for the use of chemicals are included in this publication as a convenience to the reader. The use of brand names and any mention or listing of commercial products or services in this publication does not imply endorsement by the North Carolina Cooperative Extension Service nor discrimination against similar products or services not mentioned. Individuals who use chemicals are responsible for ensuring that the intended use complies with current regulations and conforms to the product label. Be sure to obtain current information about usage and examine a current product label before applying any chemical.
For assistance, contact your county North Carolina Cooperative Extension Service agent.
Originally Prepared by: James R. Baker & S. Bambara, Extension Entomologists
Published by North Carolina Cooperative Extension Service
Distributed in furtherance of the Acts of Congress of May 8 and June 30, 1914. Employment and program opportunities are offered to all people regardless of race, color, national origin, sex, age, or disability. North Carolina State University at Raleigh, North Carolina A&T State University, U.S. Department of Agriculture, and local governments cooperating.
ENT/ort-37
April 1994 (Revised)May 1997
Web page last reviewed January, 2010 by the webperson.