CFAES COVID-19 Resources:   Safe and Healthy Buckeyes   |   COVID-19 Hub   |   CFAES Calendar. Most scale insects have hard coatings of wax on their bodies but cottony scale covers itself with fluffy filaments. They are slightly convex and are brown with a yellow-brown ridge down the back . Cooperative Extension county center. Cottony maple scale, adult females with egg sacs on twigs. Treating trees with cottony maple scale. They secrete the white, cottony masses beneath which, they lay 500 or more eggs in late May to early June. The 1/4-inch white cottony ovisac, or egg sac, is deposited on bark. Twig dieback may occur resulting in sparsely foliated canopy (Figure 2). Indians. Trunk and soil injections can be done in the fall or spring. Adult scale insects are usually covered in waxy shell-like cover. However, every few years, these natural controls seem to fail and the cottony maple scale can reach epidemic proportions. 1). This insect occurs in the northern half of Illinois. If practical, improve plant sites to reduce stress and promote growth. In late summer, the scales crawl to the twigs where they feed for the rest of the fall, winter and early spring. Adult females are about 3/16 inch long. Many systemic products are available that can be applied as foliar spray or drench. COTTONY MAPLE SCALE Lee Townsend, Extension Entomologist A mature female cottony maple scale is 1/8" long, and has a brown, flat, oval body. The cottony maple scale, Pulvinaria innumerabilis (Rathvon), is a highly modified insect pest that commonly attacks silver and red maples in Ohio. Newly hatched nymphs are pale yellow or green and translucent. This is the optimum time for control. Normally, this peculiar scale is a mere curiosity and a nuisance. These are male and female scales, respectively. Soaps and oils only kill the pests on contact. It’s cottony maple leaf scale. Insecticides . Each mass usually contains 1,000-1,500 eggs. Maple cotton scale is found on several other common hardwood trees such as ash, elm and boxelder. Damage to the host tree is caused when heavy populations of cottony maple scale withdraw sap from the plant, resulting in branch and twig dieback. In extreme cases, it is possible to lose the tree. The insect spends the winter in an immature stage on twigs and branches, maturing in late May or early June. See the North Carolina Agricultural Chemicals Manual for additional insecticide choices. Cottony Maple Leaf Scale. In extreme conditions, a tree may be killed. G = greenhouse, N = nursery, L = landscape, I = interiorscape. They closely adhere to the undersides of leaves and are easily overlooked. There are several predators and parasitoids that will naturally keep cottony maple scale populations in check. Eggs masses are conspicuously white and cottony in appearance. This scale feeds primarily on maple and dogwood in North Carolina, but it also infests hollies, Andromeda, and gum. The females mature when the plant resumes growth in the spring. In April and May, cottony maple leaf scales move to the leaves and lay up to 2,500 eggs in cottony ovisacs on the undersides (Figure 3 and Figure 4). Rarely, heavy infestations have been found to kill stressed or weakened trees. Cottony Maple Leaf Scale is one of several cottony scales in the genus Pulvinaria. 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 this situation, control is advisable. 64-10 S6 %a 3 Sporadic outbreaks of this scale insect in various parts of the United The use of brand names and any mention or listing of commercial products or services in this publication does not imply endorsement by NC State University or N.C. A&T State University nor discrimination against similar products or services not mentioned. Unfortunately, these natural enemies are also extremely susceptible to pesticide applications, so timing chemical treatments properly is very important. Cottony ovisac on maple leaf with desiccated adult female present. After mating, the males die and the females soon withdraw their mouthparts and crawl back onto small twigs and branches. Phone: 614-292-6181, © 2020 | 2120 Fyffe Road | Room 3 Ag Admin Bldg. The immatures feed on the leaves before mi-grating to the trunk to overwinter on the bark. Cottony taxus scale on yew. Cottony scales suck sap from leaves (summer) and twigs (fall, winter, early spring) depriving the tree of valuable resources. The body of the scale is white and resembles a kernel of popcorn. There are more than 25 species of scale insect found in British Gardens. Cottony Maple Scale has one generation per year, and understanding its life cycle is crucial for management of this pest, because not all pesticides will be effective at all insect life stages. Mature cottony maple scales are small, flat, oval, brown insects without obvious legs, antennae or wings. For assistance with a specific problem, contact your local Cooperative Extension center. Some premature leaf drop may result but small to moderate populations cause no harm to trees. The cottony maple scale is most easily recognized by the characteristic egg masses on twigs and branches. At maturity, the females produce the white, cottony egg masses, called ovisacs, over a period of several weeks. | Columbus, Ohio 43210. It is also reported on beautyberry, jasmine, mulberry, and hydrangea. Heavily infested branches can be killed by the cottony maple scale. They closely adhere to … Several parasites and predators have been reported for the cottony maple leaf scale.