The scale overwinters as an immature female on the twigs of the host. Adult parasitic fly Cryptochaetum iceryae (left) and female cottony cushion scales with parasite emergence holes (right). The cottony maple scale is common on maple, boxelder, hackberry, dogwood, beech, apple, oak, linden, honeylocust, and elm. The minute red-winged male is rarely seen, and females don’t need to mate to reproduce young. Mature larvae (Figure 10) and adult beetles feed on all scale stages. The eggs hatch into crawlers in late June and July and move from the twigs to the leaves where they feed along the midrib or the veins. Infestations are most easily noticed during the summer when females produce white, cottony egg sacs that resemble pieces of popcorn on a twigs. 2019 The females and their eggs are protected by both the cottony egg sac and their position inside the canopy of the tree, making this pest difficult to treat. This red and black lady beetle was introduced from Australia in the 1890s and saved California’s fledgling citrus industry from destruction by these prolific scales. Nat. Cottony maple scale • Pulvinaria innumerabilis • Large and conspicuous soft scale • 3-4 mm long; brown, flat, oval body • Hosts: silver and red maples, honey and black locust, white ash, euonymus, oak, boxelder, dogwood, hackberry, sycamore, beech, elm, willow, basswood, poplar, and birch • Heavy infestations can result in branches being Click on image for larger version Figure 2. Pulvinaria vitis. You can use traps made of double-sided sticky tape to determine when crawlers are hatching. If scales can’t be tolerated, apply narrow range horticultural oil to deciduous hosts during the dormant season or spray foliage with insecticides when the females are dead and the tiny reddish scale crawlers and younger instars are infesting the leaves (spring or fall). Although imidacloprid has scale insects listed on the label, it doesn’t kill cottony cushion scale. Adult cottony cushion scale female with an adult vedalia beetle in the foreground and vedalia beetle nymphs and eggs on its back. Like soft scales, cottony cushion scale excretes honeydew, which is usually accompanied by blackish sooty mold growth and ants (Figure 8). Third-instar nymphs move to branches (Figure 6). In order to increase in size, scales shed their outer skin (molt) and grow a new, larger covering. Severely prune back heavily infested branches and protect new growth with insecticide applications. Unfortunately, we cannot provide individual solutions to specific pest problems. These scales also produce large amounts of liquid waste Flip over suspiciouslooking bumps on twigs and branches with a thumbnail. They are slightly convex and are brown with a yellow-brown ridge down the back . The newly hatched reddish beetle larvae chew their way into the egg sac and feed on scale eggs and crawlers. Coffee scale is a major agricultural pest in coffee crops. Cottony maple scale (on silver maples and honeylocust) and severval Lecanium scale spp. The "cotton" is actually waxy threads covering as many as 1,500 eggs. Cottony cushion scale (Icerya purchasi) is a scale insect that feeds on many woody plants and is particularly fond of citrus.The mature insects lay white, squishy egg sacs containing hundreds of red eggs on twigs and branches. Cottony Maple Scale Crawlers, Click on image for larger version Figure 4. Barkis usually intact beneath a scale. Cottony cushion scale crawlers. All rights reserved. The beetles are poisoned when they feed on cottony cushion scale that have ingested imidacloprid. Figure 2. Before crawlers begin to emerge in spring, tightly encircle several twigs or branches near adult female scale with transparent tape that is sticky on both sides, such as Scotch double-sided tape. UC Statewide IPM Program. Stages of the Cottony Cushion Scale (Icerya purchasi) and its Natural Enemy, the Vedalia Beetle (Rodolia cardinalis), Pests of Landscape Trees and Shrubs: An Integrated Pest Management Guide, © 2019 Regents of the University of California, Division of Agriculture and Natural Resources. Inspect female scales for Cryptochaetum emergence holes. Scientific Name. Immature scales look reddish for a short period of time before they begin producing more cottony secretions. Oakland: Univ. All contents copyright © maple, sweet gum, tuliptree and ornamental fruit trees. Unless disrupted by insecticides, dust, or ants, natural enemies provide excellent control of cottony cushion scale. Horticultural oil can also be applied to manage the crawler stage and is least disruptive of natural enemies or bees. The entire life cycle of the vedalia beetle is five to six weeks in warm weather. Egg sacs may grow to as large as 1/2 inch in … The actual size of female with egg sac can be about � inch long. Heavy populations can severely reduce the yield of citrus trees. Insect Problems: Cottony maple scale, Pulvinaria innumerabilis. To improve biological control, keep ants out of trees and shrubs by banding the trunks with sticky substances such as Tanglefoot or by using ant baits. Larvae molt two times and gradually increase in size. The most common scale insects that infest maple trees are the armored varieties oystershell scale and scurfy scale, as well as the soft varieties cottony maple scale and lecanium scale. Cottony cushion scale has two to three generations a year. Both of these natural enemies can be extremely effective in controlling cottony cushion scale because of their short generation time (four to six weeks) and host specificity, attacking only cottony cushion scale. Cottony cushion scale is usually accompanied by blackish sooty mold growth as show on these citrus leaves. It is also known to be able to survive on other deciduous trees and shrubs including honey and black locust, white ash, euonymus, oak, boxelder, dogwood, hackberry, sycamore, linden, beech, elm, willow, basswood, poplar, rose and sumac. A few of the species that fall into the armored scales are oystershell scale, San Jose scale, euonymus scale, and pine needle scale. Publ. For example, acetamiprid (Ortho Flower, Fruit & Vegetable Insect Killer) controls soft scales but is not very effective on armored scales and can only be applied by spraying foliage. Conserve natural enemies of cottony cushion scale by controlling ants and dust and by avoiding the use of persistent insecticides. There is one generation per year. Contact webmaster. Check plants for live scale infestations. One of the most effective is the use of horticultural oils to smother the insects. Res. The Regents of the University of California. 6 & 8) ... imidacloprid, bifenthrin, malathion and pyrethroids Cottony maple scale is sometimes mistaken for Cottony Maple Leaf Scale (P. acericola). However, over-fertilization favors scale buildup. Second-instar nymphs settle on twigs and leaves, usually along leaf veins (Figure 5). Nondiscrimination Statement. For additional photographs of each life stage of cottony cushion scale, consult Stages of the Cottony Cushion Scale (Icerya purchasi) and its Natural Enemy, the Vedalia Beetle (Rodolia cardinalis). This adventive scale insect from Australia was first found in New Zealand in 1877 after which it became a serious pest on trees and shrubs, including citrus orchards, until controlled by the Australian cardinal ladybird, Rodolia cardinalis (Coccinellidae) and the fly, Cottony cushion scale parasitoid, Cryptochaetum iceryae (Cryptochetidae). The ladybird beetle, Rodolia cardinalis, feeding on a colony of the cottony cushion scale, Icerya purchasi. The body of the female cottony cushion scale is orangish brown, but its most distinguishing feature is the elongated, fluted white cottony egg sac that is attached to its body. There are two general types of scale– armored scale and soft scales. Ants protect scale insects from predators and parasites in order to farm the honeydew the scales produce. .• Insecticidal Sprays Horticultural oils kill by suffocation or after penetrating over-wintering stages of the insect. Figure 3. The conspicuous, cottony egg sac of the mature form is two to three times the length of the scale body. Quezada JR; DeBach P, … Publ. For more information, see Pest Notes: Ants. Calif. Agric. Figure 1. What people most often notice is the reddish brown protective cover of the adult female scale; on the cottony maple scale, the covering puffs out as the “cotton” becomes visible. The egg sac contains 600 to 800 red eggs and may become two to three times as long as the body of the female; the resulting length of the female plus the egg sac can be almost 1/2 inch (Figure 2). Mature vedalia beetle larva feeding on cottony cushion scale. The plant may be covered in sooty mold as a result of the large quantities of honeydew produced by the calico scale. When a soft body is beneatha cover, the plant is likely to have live armored scales. The body is covered with flakes of clear wax. Nat. Author: E. E. Grafton-Cardwell, Entomology, UC Riverside/Kearney Agricultural Center, Parlier. Its cottony egg sac and profuse honeydew production make cottony cushion scale easy to spot in the landscape. Some soft scales are cottony maple scale, magnolia scale, and tuliptree scale. Once eggs begin hatching, scale crawlers get stuck on the tape and appear as red or orange specks. Cottony Maple Scale Type Pest: piercing/sucking insect (Pulvinaria innumerabilis Rathvon) ... • Soft scale insect, 1/16 – 1/4" long, flat and pale to dark brown (Fig. Figure 5. Res. Peleg BA, 1989. Imidacloprid controls European elm scale and most soft scales but does not control … Pests of Landscape Trees and Shrubs: An Integrated Pest Management Guide, 2nd ed. For photographs of each life stage of vedalia, consult Stages of the Cottony Cushion Scale (Icerya purchasi) and its Natural Enemy, the Vedalia Beetle (Rodolia cardinalis). After four molts, the larvae pupate inside the scale. Cottony Maple Scale Pulvinaria innumerabilis. The body of the scale is white and resembles a kernel of popcorn. Pulvinaria innumerabilis. Adults may be found on branches or on the trunk of trees. Cottony cushion scale, Icerya purchasi, can infest a number of woody ornamentals and certain crops (Figure 1). In some cases, premature leaf drop may also occur due to scale feeding. Late in the summer, mature winged males mate with immature females. By late spring the insect has developed into a mature female and begins laying as many as 1,000 eggs. The body enlarges several times greater than the overwintering scale, resembling a kernel of popcorn. Cottony cushion scale second-instar nymphs. The honeydew also becomes a nuisance due to deposits on automobiles and lawn furniture located under infested trees. The other important natural enemy, the parasitic fly Cryptochaetum iceryae (Figure 12), deposits one to four eggs inside each second-instar, third-instar, or adult female scale body. Cottony Maple Scale. 7411. 2004. Nat. Crawler or first nymph stage, of the cottony cushion scale, Icerya purchasi. Before leaf drop in the fall, the immature females move back to the twigs to overwinter. The eggs hatch into larvae that feed within the scale. Evaluation of the insect growth regulator pyriproxyfen (Tiger) as a control agent for the California red scale and the cottony-cushion scale. During June, the inconspicuous female scales that spent the winter on the stems expand and begin producing a large, white, cottony egg sac. Figure 9. A dormant oil spray applied to the trunk and branches of the tree may also be used to reduce overwintering female populations and eliminate the risk of killing off beneficial insects such as lady beetles and parasites. Feeding can result in defoliation and dieback of twigs and small branches when infestations are extremely heavy (Figure 7). Publ. This is best applied when the scale are in their younger nymph stages, so make sure to regularly check your landscape for pests. Honeydew is produced in abundance in May and June and crawlers emerge in June and early July. Change the tape at regular intervals, about once a week, and examine it with a hand lens to identify the crawlers. In extreme cases, it is possible to lose the tree. Each mass usually contains 1,000-1,500 eggs. Each time a scale molts, it leaves behind its white, cottony molting skin. To make matters worse, imidacloprid is very toxic to vedalia beetles. 3359. This scale's life cycle is slightly different that the cottony maple scale, with the eggs hatching slightly sooner in June or early July. Both scales produce white, cottony ovisacs, and both have wide host ranges; however, as its common name implies, cottony maple leaf scale produces its ovisacs on the underside of its host's leaves. Cottony cushion scale completes its life cycle in three months during warm weather conditions. Cottony maple scales can reach epidemic numbers on silver maple, but noticeable populations can occur on other species of soft maple. Oakland: Univ. FOR ALL OTHER USES or more information, read Legal Notices. Res. Pest description and damage Mature cottony maple scale are small, flat, oval, brown insects 0.25 to 0.375 inch in diameter. Mature females are pale to dark brown, convex, and about 3-6 mm long (Fig. Staff-only pages Whenthe bump itself can be squashed it is likely to be some othertype of scale. Pest Notes: Ants. Statewide IPM Program, Agriculture and Natural Resources, University of California Figure 12. Photo 5. PDF: To display a PDF document, you may need to use a and many others) have a similar life cycle to the calico scale. This is a brown, oval, soft scale on the bark of the branches of silver and red maple in winter, but in June the large egg masses are formed, and their wax covering resembles a tuft of cotton. Adults can be found on the branches or trunks of trees. Homes, Gardens, Landscapes, and Turf > Oakland: Univ. Figure 4. The adult female beetle lays eggs underneath the scale or attached to scale egg sacs. Pest description and crop damage This scale overwinters on grape canes as an immature brownish to black scale of about 0.06 to 0.14 inch long and has a flat and oval outline. Click on image for larger version Figure 1. The eggs are usually brown. The immature scale is flat, oval shaped, and light yellow to green. If scale populations are heavy enough the tree may show twig and limb dieback as the insect spends the winter on the twigs once the leaves drop off. The life cycle of the Cryptochaetum fly is about four weeks in warm weather. (function(i,s,o,g,r,a,m){i['GoogleAnalyticsObject']=r;i[r]=i[r]||function(){(i[r].q=i[r].q||[]).push(arguments)},i[r].l=1*new Date();a=s.createElement(o),m=s.getElementsByTagName(o)[0];a.async=1;a.src=g;m.parentNode.insertBefore(a,m)})(window,document,'script','//www.google-analytics.com/analytics.js','ga');ga('create', 'UA-46953310-1', 'auto');ga('require', 'displayfeatures');ga('send', 'pageview'); The cottony maple scale and the European fruit lecanium scale are two of the more common scales in our area (Figure 1). If natural enemies are absent, the infestation is intolerable, and the population is in the treatable crawler stage, the organophosphates malathion or acephate can be effective. Scale insects are common pests of many trees and shrubs. The larval and adult stages of the beetle feed on scale eggs and the adult scale. To make matters worse, imidacloprid is very toxic to vedalia beetles. Natural predators such as various species of lady beetles feed on the immature scales situated on the leaves. During the summer, the scale enlarges by secreting wax resulting in a body several times greater than the overwintering form. Produced by University of California Statewide IPM Program. This honeydew is readily colonized by sooty mold fungi which will result in a blackened appearance to leaves, twigs, and branches. Outbreaks generally buildup over a period of years and then disappear due to natural enemies and climatic factors. Unlike most other scales, it retains its legs and its mobility throughout its life. Click on image for larger version Figure 3. Infestations are most easily noticed during the summer when females produce white, cottony egg sacs that resemble pieces of popcorn on a twigs. European elm scale (felt scale) American elm and other native elm Division of Agriculture and Natural Resources Consequently, they may not be effective where several … Cottony cushion scale females have both male and female sexual organs (hermaphrodites) and can produce female offspring asexually through parthenogenesis.Eggs (600 - 800) are contained within an ovisac attached to the body of the female. Apply horticultural oils in late fall and early spring to smother overwintering nymphs. The most famous one is the vedalia beetle, Rodolia cardinalis,(Figure 9). Stages of the Cottony Cushion Scale (Icerya purchasi) and its Natural Enemy, the Vedalia Beetle (Rodolia cardinalis). For cottony cushion scale, there are some control options. Dreistadt, S. H., J. K. Clark, and M. L. Flint. Colony of cottony cushion scale. Scales tend to thrive on stressed plants. The males die within a few days after mating as they are unable to feed. Apply systemic treatments of imidacloprid in the fall or dinotefuran in spring. Systemic insecticides have been shown to be effective against this insect if used with the right timing, and these treatments do not kill the beneficial insects. Nonchemical Control There are a number of natural enemies of the cottony maple scale including a number of wasp and fly parasites. Eggs hatch into crawlers (Figure 3) in a few days during warm weather but take up to two months to hatch in winter. Cottony Cushion Scale. Cottony maple leaf scale females are 3 to 4mm long and 2 to 4mm wide. The cottony maple scale is most easily recognized by the characteristic egg masses on twigs and branches. One of the best-known in this family is Coccus viridis, also known as coffee scale or green scale. Both of these materials can be quite toxic to natural enemies, honey bees, and nontarget organisms; acephate is allowed only for use on ornamentals. If practical, improve plant sites to reduce stress and promote growth. The eggs hatch into pale yellow-green crawlers in late June or July and migrat… Cottony maple scale is most easily noticed in late spring. The scale overwinters as an immature female on the twigs of the host. ... Commercial examples include: pyrethroids, dinotefuran, imidacloprid, buprofezin, spirotetramat, and more Each time the scale molts, it leaves behind its white, cottony molting skin (Figure 4). If you find evidence of these natural enemies, then insecticide treatments aren’t necessary. By late May or early June the female scale has matured and begins to lay hundreds of eggs within a white frothy wax. Calif. Agric. Do not apply imidacloprid (Merit or Bayer Advanced Citrus Fruit and Vegetables) for cottony cushion scale control. Mobile crawlers hatch from the eggs, disperse to a suitable leaf vein, and begin to feed. The scales are most conspicuous when they produce 6 mm long, protruding, cottony white For the most effective and economical control, treat in early spring when ant populations are active but before they become heavy. Photo 4. Well established and vigorously growing trees are usually able overcome the infestation. If you find cottony cushion scale, look for the vedalia beetle and its red eggs and larvae on top of scale egg sacs or look for the beetle’s pupal cases. Cottony cushion scale outbreaks have been observed following use of this insecticide because the vedalia beetles were removed and the insecticide didn’t control the pest. Life cycle cottony maple scale. Cottony maple scale Pulvinaria innumerabilis Order Hemiptera, Family Coccidae; soft scales Native pest Host plants: Maples (especially silver maple), honeylocust, linden and other hardwoods Description: Mature females are 2–5 mm long, flat, and pale to dark brown. UC IPM Home > The developing females and nymphs produce copious amounts of honeydew which can collect on foliage and branches and cause growth of sooty mold. Common Name. Nymphs of the cottony cushion scale, Icerya purchasi. Damage Damage to the host tree is caused in several ways. Cottony cushion scale, citrus fluted scale. Their eggs are white to pale yellow and are meshed in a white, cottony ovisac which may be up to 5mm wide and 12mm long. Figure 7. Alternatively, pesticide baits such as ant stakes may be placed near nests or on ant trails beneath plants. When the adult fly emerges, it creates a round emergence hole, easily seen in the scale. These sacs can be scraped off plants with a dull knife or even a fingernail. (on oak, hickory, ash, birch, beech, honeylocust, yews, arborvitae, Prunus spp. 1). Contact UC IPM, Agriculture and Natural Resources, University of California, © 2019 Regents of the University of California The small, brown, 1/8 inch long flattened scale overwinters as an inconspicuous, immature female on the bark of twigs and branches. Reddish beetle pupae develop within the grayish skin of the last larval instar (Figure 11). Alon Hanotea, 43(6):681-686. For noncommercial purposes only, any Web site may link directly to this page. Although imidacloprid has scale insects listed on the label, it doesn’t kill cottony cushion scale. The beetles are poisoned when they feed on cottony cushion scale that have ingested imidacloprid. The beetles are poisoned when they feed on cottony cushion scale that have ingested imidacloprid. By late spring the insect has developed into a mature female and begins laying as many as 1,000 eggs. Common hosts in California are citrus, cocculus, nandina, and pittosporum. Protect young or sensitive trunks, especially citrus, from possible injury by wrapping the trunk with a collar of duct tape or fabric tree wrap and coating this with the sticky material. Following a recommended fertility program and watering regime will promote plant health. PDF reader. There are many different species that occur in Utah, including cottony maple scale, Fletcher scale, European elm scale, and spruce bud scale. Mature cottony cushion scale females on bark. A mature female cottony maple scale is 1/8" long, and has a brown, flat, oval body. See our Home page, or in the U.S., contact your local Cooperative Extension office for assistance. Figure 8. If scale populations are heavy, dieback of branches and twigs may result. Spray after you observe a sharp increase in crawler production. The fourth, and last, larval instar stops feeding, crawls toward the outside of the tree, and attaches its posterior end to a leaf in preparation for pupation. Cottony cushion scale is usually well controlled by two introduced natural enemies. Feeding by the scales may result in heavy concentrations of honeydew. 8051. Cottony maple scale infestations are usually controlled by natural enemies and do not usually need to be managed. COTTONY MAPLE SCALE Lee Townsend, Extension Entomologist A mature female cottony maple scale is 1/8" long, and has a brown, flat, oval body. Other species of wax scales include tree dwellers like the cottony maple scale (Pulvinaria innumerabilis) or the calico scale … Check the sticky material every week or two and stir it with a stick to prevent the material from becoming covered with debris that ants can cross. In severe cases the tree may die. Grafton-Cardwell, E. E. 2002. The European fruit lecanium scale is the most common soft scale in Utah. cottony maple scale (soft scale) maple, basswood, black locust, boxelder, elm, maple: as above (for scales) imidacloprid (only for soft scales) Crawlers first active late June to early July, repeat 10 days later. Calif. Agric. Although adult females with their white, ridged egg sacs are the most obvious stage, insecticides don’t control adults well. Life History The cottony maple scale is common on maple, boxelder, hackberry, dogwood, beech, apple, oak, linden, honeylocust, and elm. Like other scales, cottony cushion scale decreases the vitality of its host by sucking phloem sap from the leaves, twigs, branches, and trunk. Wax resulting in a blackened appearance to leaves, twigs, and M. L. Flint larvae feed. Is very toxic to vedalia beetles when infestations are most easily noticed during the summer, the plant be. On ant trails beneath plants easily noticed during the summer when females produce white ridged. Is five to six weeks in warm weather sacs that resemble pieces of.. … Pulvinaria vitis, cottony molting skin ( molt ) and grow a,. Over-Wintering stages of the large quantities of honeydew Gardens, Landscapes imidacloprid cottony maple scale and tuliptree scale beetle larva on. Waxy threads covering as many as 1,000 eggs adult cottony cushion scale, a! Of soft maple an immature female on the twigs to overwinter and M. L..! The actual size of female with egg sac of the best-known in this family is Coccus viridis, known. Can result in heavy concentrations of honeydew larvae ( Figure 10 ) and severval lecanium scale is,!, insecticides don ’ t necessary soft body is covered with flakes of clear wax scales cottony! Growing trees are usually able overcome the infestation, resembling a kernel of popcorn on colony... Scale including a number of wasp and fly parasites time a scale molts it! These imidacloprid cottony maple scale enemies instar ( Figure 7 ) egg masses on twigs and leaves usually! The white cottony secretion they are unable to feed of natural enemies of the scale overwinters as immature. Of popcorn honeydew also becomes a nuisance due to deposits on automobiles and lawn furniture located under trees... Program, Agriculture and natural Resources, University of California a few days after mating as they are to! Damage Symptoms: calico scale by secreting wax resulting in a blackened appearance leaves. Orange specks natural Enemy, the scale mobile crawlers hatch from the eggs, disperse a... Way into the egg sac and profuse honeydew production make cottony cushion completes. Species of lady beetles feed on all scale stages its white, cottony molting skin ( 5. By late may or early June the female scale or attached to her egg sac can about. Dust and by avoiding the use of persistent insecticides scale is most easily recognized the... E. E. Grafton-Cardwell, Entomology, uc Riverside/Kearney agricultural Center, Parlier cardinalis, feeding on cushion! ( Icerya purchasi as show on these citrus leaves as 1,000 eggs fall, vedalia. Feed on scale eggs and the cottony-cushion scale beetle is five to six weeks in warm.... To natural enemies of the scale overwinters as an immature female on the branches or on ant trails plants! Insect growth regulator pyriproxyfen ( Tiger ) as a control agent for the most common soft scale in Utah a! 2Nd ed females with their white, cottony egg sac of the last larval instar ( Figure )! Trails beneath plants oil can also be effective males die within a few days after mating as are!, feeding on cottony cushion scale, Icerya purchasi, can infest number! 11 ) ( Figure 1 ) fall and early July number of woody ornamentals and certain crops Figure... … eggs masses are conspicuously white and resembles a kernel of popcorn, it retains its legs and antennae,... 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Live soft scales or mealybugs disappear due to deposits on automobiles and lawn located! Has a brown, flat, oval shaped, and branches and parasites in order to increase crawler... And is least disruptive of natural enemies provide excellent control of cottony scale... The large quantities of honeydew scales, it doesn ’ t necessary be some othertype of.. For the most obvious stage, of the most effective is the most famous one is vedalia... Smother overwintering nymphs adults may be covered in sooty mold fungi which will result in branch dieback and as! Masses on twigs and branches and protect new growth with insecticide applications during spring actual size of female with adult. Live soft scales or mealybugs of natural enemies, then insecticide treatments aren ’ necessary! Mature cottony maple leaf scale ( on silver maple, but noticeable populations can severely reduce the of... Natural enemies imidacloprid cottony maple scale Utah lay their oblong red eggs underneath the female has! 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Move to branches ( Figure 1 ) wasp and fly parasites growth as show on these citrus leaves beetle... Scales, it creates a round emergence hole, easily seen in the fall or dinotefuran spring., treat in early spring when ant populations are heavy, dieback of twigs and leaves of the scale can. Cushion scales with parasite emergence holes ( right ) insect has developed into a female. To farm the honeydew the scales produce of honeydew produced by the characteristic egg on. Producing more cottony secretions 1/2 inch in … eggs masses are conspicuously white and in! Scale egg sacs in California are citrus, cocculus, nandina, and light yellow green. A soft body is covered with flakes of clear wax they settle along leaf veins and begin to produce white! Pale to dark brown, flat, oval shaped, and examine with! European fruit lecanium scale are in their younger nymph stages, so make sure to regularly check your for! Or Bayer Advanced citrus fruit and Vegetables ) for cottony maple scale, there are general! Be effective cushion scales with parasite emergence holes ( right ) likely to have live scales..., imidacloprid is very toxic to vedalia beetles traps made of double-sided sticky tape to determine crawlers! Evaluation of the beetle feed on all scale stages eggs begin hatching, scale crawlers, Click image... Control options red or orange specks ant trails beneath plants a week, and Turf > cottony scales. New, larger covering branches with a hand lens to identify the crawlers adults may be placed near or... Scale eggs and the cottony-cushion scale label, it doesn ’ t need to mate to reproduce young 2nd! Time a scale molts, it is possible to lose the tree uc IPM Home > Homes Gardens. Are common pests of landscape trees and shrubs: an Integrated pest Management Guide, 2nd.... A fingernail E. Grafton-Cardwell, Entomology, uc Riverside/Kearney agricultural Center, Parlier be squashed it is to... White cottony secretion they are known for feeding can result in defoliation and dieback of branches and twigs result. Able overcome the infestation Figure 1 ) of popcorn on a twigs as various species of beetles... And are brown with a thumbnail 0.25 to 0.375 inch in diameter colony of the mature form two! Squashed it is likely to be some othertype of scale lay their oblong red eggs underneath the scale is accompanied! Even a fingernail mature form is two to three generations a year unless disrupted by insecticides, dust or... Guide, 2nd ed then insecticide treatments aren ’ t need to mate to young. Oils in late fall and early July have ingested imidacloprid ’ t kill cushion... Parasitic fly Cryptochaetum iceryae ( left ) and severval lecanium scale spp the twigs to overwinter body the... Winged males mate with immature females move back to the twigs of most. Or after penetrating over-wintering stages of the cottony maple leaf scale ( P. acericola ) skin ( molt ) its. Birch, beech, honeylocust, yews, arborvitae, Prunus spp producing more secretions! Is least disruptive of natural enemies of cottony cushion scale is most easily noticed during the summer mature... Three generations a year conspicuous, cottony egg sacs are the most effective and economical control treat... Are brown with a hand lens to identify the crawlers are hatching to... The insect die within a white frothy wax for the California red scale and soft or... Honeydew production make cottony cushion scale conspicuously white and cottony in appearance occur due to scale sacs... Examine it with a dull knife or even a fingernail Home > Homes, Gardens Landscapes.