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Home , Asterolecaniidae, Asterolecanium, Barnacle, Coccus hesperidum, Honeydew (secretion), Margarodidae

SCALES

Integrated Management for Home Gardeners and Landscape Professionals

Scale can be serious pests on of scales and their tree and trees, shrubs, and other perennials. shrub hosts are listed in Tables 1–3. The impact of infestations depends Excellent color keys for scale insects on the scale species, the plant species in California are available from the and , environmental factors, California Department of Food and and natural enemies. Populations of Agriculture; see References for titles. some scales can increase dramatically within a few months, such as when It is important to correctly distinguish -seeking or dusty the scale family to which your pest conditions interfere with scale natural species belongs. For example, a popular enemies. Plants are not harmed by a systemic (imidacloprid, few scales, and even high populations discussed below) controls European of certain species apparently do not elm scale and most soft scales but damage plants. Soft scales and some does not control armored scales or Figure 1. Armored scale infestation on twig. other species excrete honeydew, a sweet, cottony cushion scale. Imidacloprid sticky liquid produced by insects that can dramatically increase cottony scales feed in the fluid-conducting ingest large quantities of plant . cushion scale populations because it is phloem tissue of the plant and excrete Sticky honeydew and the blackish sooty very toxic to one of its natural enemies, abundant honeydew, which is sugary mold growing on honeydew can bother the vedalia , Rodolia cardinalis. water that drips from their bodies. Soft people even when scale populations are This important cottony cushion scale scales include black scale, brown soft not harming plants. predator is poisoned by feeding on scale, European fruit lecanium scale, scales that have ingested the insecticide. and various species. IDENTIFICATION Armored Scales. Scales are unusual looking and many Armored scales, Other Species of Scale. Species people do not at first recognize them as family , have a flattened, in other families include 1 insects. Adult female scales and most platelike cover that is less than /8 inch cottony cushion scale and sycamore immatures () are immobile, in diameter. The actual insect body scale (the woolly sac scales, family wingless, and lack a separate head is underneath the cover. The covers ), European elm scale or other recognizable body parts. often have a differently colored, slight (felt scales, ), and pit Immature scales and adult females protuberance (exuviae, or “nipple”). scales (). have a characteristic round or oval Concentric rings form as each nymphal to elongate and flattened or humped stage () secretes an enlargement Scale Look-Alikes. Various other appearance. Immature males are often a to its cover (Fig. 1). Armored scales organisms may be confused with scales. different color and shape than females, do not excrete honeydew. Damaging These include California laurel especially in later nymphal stages species include California red scale, (Euthoracaphis umbellulariae), coconut (). Adult male scales are tiny, scale, oystershell scale, and (Nipaecoccus nipae), cypress delicate insects with one pair of wings. San Jose scale. bark mealybug (Ehrhornia cupressi), Adult males are rarely seen, do not feed, parasitized whitefly nymphs, and and live only a few hours. Soft Scales. Soft scales, family , psyllids such as lemongum lerp psyllid can be smooth, cottony, or waxy and (Cryptoneossa triangula) and redgum Scales insert a tiny strawlike mouthpart are 1⁄4 inch long or less. They are lerp psyllid (Glycaspis brimblecombei). into plants and suck fluids. Scales can usually larger and more rounded and Diamond “scale” infesting palms occur on bark, fruit, or leaves. Armored convex than armored scales. Their is actually the fruiting bodies of scales and soft scales are the most surface is the actual body wall of the Sphaerodothis neowashingtoniae, an common groups (families). Common insect and cannot be removed. Soft Ascomycetes !

EST OTES Publication 7408 PUniversity of California N Agriculture and Natural Resources revised March 2007 March 2007 Scales

LIFE CYCLE Females of many scale species reproduce without mating (there are no males). At maturity, adult females produce eggs that are usually hidden under her body or cover. Eggs hatch second-instar virgin female gravid female female adult (underside) into tiny crawlers (mobile first-instar nymphs), which are yellow to orangish crawler white cap in most species. Crawlers walk over nipple stage the plant surface, are blown by wind to other plants, or can be inadvertently moved by people or birds. They settle first instar down and begin feeding within a day or two after emergence. second-instar third- and fourth-instar male male (underside) male adult Settled nymphs may spend their entire life in the same spot without moving as they mature into adults. Nymphs Figure 2. Life stages of a typical armored scale, the California red scale. of other species can move slowly but rarely do, such as when species scales (Margarodidae), and some that feed on deciduous hosts move scorched appearance. Several years other species produce distinct external from foliage to bark in the fall before of severe infestations may kill young cottony or -covered egg masses. leaves drop. For species with multiple plants. Certain armored scales may be generations, all scale life stages may more likely to kill plants. Soft scales DAMAGE be present throughout the year in reduce plant vigor, but seldom kill trees When plants are heavily infested areas with mild winters. Life cycles or shrubs. and stages for scales are illustrated in with scales, leaves may look wilted, Figures 2 and 3. turn yellow, and drop prematurely. MANAGEMENT Scales sometimes curl leaves or cause Scales are often well controlled by deformed blemishes or discolored Armored Scales. Most armored scales beneficial predators and parasites, have several generations a year. halos in fruit, leaves, or twigs. Bark except when these natural enemies are Armored scales overwinter primarily as infested with armored scales may disrupted by ants, dust, or application of first-instar nymphs and adult females. crack and exude gum. Certain armored persistent broad-spectrum . Except for crawlers and adult males, scales also feed on fruit, but this Preserving (conserving) the populations armored scales spend their entire damage is often just aesthetic. Soft of parasites and predators (such as by life feeding at the same spot. Settled scales infest leaves and twigs but rarely controlling pest-tending ants) may be armored scales lose their legs, molt, and feed on fruit. A major concern with soft enough to bring about gradual control form their characteristic covers, which scales is their excretion of abundant of scales as natural enemies become they gradually enlarge as they grow. honeydew, which contaminates fruit, more abundant. If scales become too leaves, and surfaces beneath plants. numerous, a well-timed and thorough Soft Scales. Most soft scales have one Honeydew encourages the growth spray using horticultural (narrow-range) generation each year and overwinter of black sooty mold and attracts ants, oil applied either during the dormant as second-instar nymphs. The multi- which in turn protect scales from season or soon after scale crawlers are generational brown soft scale is an natural enemies. active in late winter to early summer important exception Brown soft scale should provide good control. Complete females and nymphs of various size When numerous, some scale species spray coverage of infested plants (such can be present throughout the year. weaken plants and cause them to as the underside of leaves) is needed to Most immature soft scales retain grow slowly. Branches or other plant obtain good control. Thorough spray their barely visible legs and antennae parts may die if they remain heavily coverage is especially critical when after settling and are able to move, infested with scales. If plant parts die treating armored scales and oak pit although slowly. At maturity, females quickly, dead brownish leaves may scales, as these scales are generally less of certain soft scales, the woolly sac remain on branches, giving them a susceptible to than soft scales.

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spring/summer Central Valley of California. This mature females pruning increases scale mortality as a crawlers result of heat exposure. eggs beneath female scale When landscaping, choose plants that are relatively pest-free and well adapted to local conditions. Consider settled replacing problem prone plants. Most first females before instars pests are highly specific. Scales egg laying that can feed on many different plants second instars on twig usually damage only certain of these fall/winter plant species and though present, do not damage other species or in the same plant . Notable exceptions include California red scale Figure 3. Life cycle of a typical soft (family Coccidae). (which can severely infest and damage situations. Honeydew dropping from all species) and San Jose scale Monitoring plants can be efficiently monitored (which damages many different fruit Inspect plants to determine whether using water-sensitive paper, which and nut trees). female scales, nymphs, honeydew, or is commonly used for monitoring sooty mold are present. When assessing insecticide droplets and calibrating Biological Control whether scales or their damage are sprayers. Products include bright Scales are often controlled by small abundant enough to prompt you to yellow cards that produce distinct blue parasitic and predators including manage them, distinguish live scales dots upon contact with honeydew or , bugs, lacewings, and mites. from dead or parasitized ones by water. Regularly monitoring honeydew Predatory Chilocorus, Hyperaspis, flipping over the female scale body beneath plants (such as the number and species lady beetles or cover using a sharp tool. The dead of drops during four hours, once a (ladybugs) can easily be overlooked scales from previous generations can week) can help to develop thresholds because many are tiny, colored and remain on plants, and sometimes a and evaluate effectiveness of the shaped like scales, or feed beneath large proportion of scales are dead or treatment. Honeydew monitoring is scales. Hyperaspis species are tiny, shiny, parasitized by natural enemies. During useful where there is a low tolerance for black lady beetles with several red, the growing season, inspect trunks dripping honeydew, when managing , or yellow spots on the back. for ants. If the descending ants have many trees (such as along city streets has a reddish head swollen, almost translucent , or in parks), and on tall trees where and underside, and a grayish back they are probably feeding on honeydew the honeydew-producing insects may densely covered with tiny hairs. The produced by scales or other insects that be located too high to easily observe. twicestabbed lady beetle, Chilocorus suck plant juices. Tracing back trail- For more information on monitoring orbus, is shiny black with two red spots making ants can lead you to colonies of honeydew, see the section in on its back, and reddish underneath. the honeydew-producing insects. Pests of Landscape Trees and Shrubs listed The multicolored Asian lady beetle, in References. , is a relatively Action thresholds before spraying large, variably colored species. It is have not been established for scales Cultural Control mostly orange, red, or yellow with in most situations. Monitor and Provide plants with good growing 19 large dark spots, or fewer, smaller, record scale densities and use the conditions and proper cultural care; or no spots on its wing covers. The density that caused damage (dieback especially appropriate irrigation, so alligatorlike larvae of lady beetles or unacceptable honeydew) as your they are more resistant to scale damage. often occur openly on plants. In certain preliminary control action threshold. Prune off heavily infested twigs and species, small larvae are hidden under Refine this threshold over time for your branches to eliminate scales when the female scale body or cover where local situation as you gain experience. infestations are on limited parts of the they feed on scale eggs and crawlers. plant. Pruning to open up tree canopies Tape traps for crawlers discussed in the helps to control black scale, citricola Parasitic wasps are often the most Foliage Sprays section and honeydew scale, and possibly other species in important natural enemies of scales monitoring are useful in certain areas with hot summers, such as the (Figure 4). Parasites include many

◆ 3 of 8 ◆ March 2007 Scales species of Aphytis, Coccophagus, , Control and Metaphycus. The female Control ants if large lays one or several eggs in or on each numbers of them are scale, where the tiny maggotlike wasp climbing up trunks larvae feed. When parasitized, some to tend scales. Deny scales are darker-colored than normal. ants access to plant Estimate parasite activity before canopies by pruning making a treatment decision. Check branches or weeds for discolored (parasitized) scales and that provide a bridge scale covers with round exit holes made between buildings by emerging adult parasites. Lift the or the ground and covers of armored scales and examine by applying a sticky beneath them for immature parasites. material (such as Tanglefoot) to trunks. Natural enemies, or beneficial insects, Wrap the trunk with are commercially available for release a collar of fabric tree against California red scale and wrap, heavy paper, or masking tape to perhaps certain other scales. However, avoid injury to bark; conserving resident natural enemies wedge pliable wrap is a more efficient and longer lasting snugly into cracks and strategy than buying and releasing crevices; and coat the beneficials in gardens and landscapes. wrap with the sticky material. A barrier Ant control, habitat manipulation, and band about 2 to 6 Figure 4. Life cycle of a scale parasite. A. Female parasites management are the key inches wide should lay one or several eggs in or on each scale . conservation strategies. Grow flowering B. Larvae emerge from the eggs and feed as immature be adequate in most plants near scale-infested trees and parasites shown here on a scale that is flipped upside down. situations. Increase the C. Parasites pupate and develop into adults. D. A roundish shrubs to help attract and support longevity of the sticky hole in the dead scale is chewed by an emerging adult para- natural enemies. Adults of predatory material by applying site. F. The female wasp seeks scale nymphs to parasitize. bugs, lacewings, lady beetles, and it higher above the parasitic wasps live longer, lay more ground to reduce before they die, workers will spread eggs, and kill more scales when they contamination by debris and sprinkler the toxicant among many other ants have plant nectar or pollen and insect wash-off. honeydew to feed on. Minimize dust, during food sharing. Boric acid, which interferes with natural enemies. Do not wrap trunks too tightly. Inspect fipronil, and hydramethylnon are For example, wash plant surfaces wraps at least several times a year for examples of insecticides used in ant midseason, or when the foliage is damage to bark, such as constricted baits. Although baits act slowly over covered with dust. growth or injured tissue. Remove and a period of hours to weeks (requiring relocate any wrap at least once a year users to be patient), baits can be much Depending on the scale species and to minimize bark injury. Check sticky more effective than sprays. Sprays only the extent to which biological control material at least every 1 to 2 weeks; kill foraging workers, while ant baits has been disrupted, it will take several stir it with a stick to prevent ants from are carried back to their nests, where months of conservation efforts (such as crossing on collected debris. Avoid reproductive queens and the entire controlling ants and dust and avoiding applying sticky material to horizontal colony underground can be killed. See application of persistent insecticides), surfaces where birds may roost. Pest Notes: Ants in References for more or until the next season or longer, information. before scale populations are reduced Alternatively, or as a supplement, place by biological control. If current levels enclosed pesticide baits (insecticide Chemical Control of Scales of scales are intolerable, use a short mixed with an attractant) such Horticultural oil (where plants can residual insecticide such as oil or soap as ant stakes near nests or on ant be sprayed) and certain systemic to reduce scale populations while trails beneath plants. Effective bait insecticides are preferred chemicals conserving natural enemies. insecticides are slow-acting, so that for most situations when scales are

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numerous enough to cause damage. because susceptible stages of these citricola scale on hackberry found pests are not present during winter. spraying oil on foliage once during late Dormant Season Sprays. Dormant spring after most crawlers emerged season application of a narrow-range Oil Use and Precautions. Horticultural was as effective as using a systemic or horticultural oil is effective against oils are specially refined petroleum organophosphate (acephate). most scale pests on deciduous woody products, often called narrow-range, plants. A good time to apply oil is when superior, or supreme oils. Some Avoid products called dormant oil or no rain or fog is expected within a day. botanical (plant-derived) oils are also dormant oil emulsions. These are more On leafless host plants, application available. Thoroughly spraying plants likely to injure plants. Do not apply oil can be made any time when weather at the proper time with oil alone when it is foggy, freezing (under 32°F), is suitable during dormancy to control usually provides adequate control. One hot (over 90°F), or rainy, or within a day lecanium scales, San Jose scale, walnut study of sycamore scale found that of when these conditions are expected. scale, and many other species. For oak organophosphates (e.g., malathion) or If leaves are present, to avoid oil injury, pit and sycamore scales, spray during organophosphates combined with oil be sure only to apply to well watered the delayed-dormant period, which is were no more effective than a thorough plants. Do not apply horticultural oil to after the buds swell but before buds spray of oil or alone, deciduous trees within 30 days before or open. Do not spray oystershell or if properly timed during the delayed- after application of captan, sulfur, or certain scales during the dormant season dormant period. Another study of other fungicides to avoid damage to trees.

TABLE 1. Some Common Armored Scales (Diaspididae), Their Impact in California, and the Principal Hosts.

Common Name (Scientific Name) Susceptible Hosts and Impact Hosts Usually Not Damaged

California red scale ( aurantii) citrus highly susceptible in Central acacia, boxwood, eugenia, euonymus, grape, Valley; biologically controlled in magnolia, mulberry, olive, palm, podocarpus, Southern California privet, rose scale (Furchadaspis zamiae) (sago palm) severely infested bird-of-paradise euonymus scale (Unaspis euonymi) Euonymus japonica highly Euonymus kiautschovica (=E. sieboldiana) susceptible tolerant, E. alata unaffected greedy scale (Hemiberlesia rapax) generally not damaging acacia, bay, boxwood, ceanothus, , fruit trees, holly, ivy, laurel, magnolia, manzanita, palm, pepper tree, , pyracantha, redbud, strawberry tree, latania scale () generally not damaging, except on acacia, avocado, Cedrus, English ivy, euonymus, kiwifruit Fatsia, fuchsia, gladiolus, grevillea, Kentia, philodendron, rose, Rubus, Salix, yucca minute cypress scale (Carulaspis minima) Cupressus sempervirens highly arborvitae, cypress, juniper susceptible obscure scale (Melanaspis obscura) biologically controlled chestnut, , pecan oleander scale ( nerii) generally not damaging acacia, aucuba, bay, boxwood, cactus, holly, ivy, laurel, magnolia, manzanita, maple, mulberry, oleander, olive, palm, pepper tree, redbud, sago palm or cycad, Taxus (yew), yucca olive scale (Parlatoria oleae) biologically controlled olive oystershell scale () poplars and especially alder, aspen, box elder, boxwood, ceanothus, susceptible cottonwood, most deciduous fruit and nuts, holly, maple, sycamore purple scale () biologically controlled citrus San Jose scale (Quadraspidiotus nut and stone fruit trees can be acacia, aspen, citrus, cottonwood, most maple, perniciosus) highly susceptible mulberry, poplar, pyracantha, rose, strawberry tree, willow walnut scale (Quadraspidiotus juglansregiae) biologically controlled walnut

“Biologically controlled” species are usually not damaging, but can become pests if their natural enemies are disrupted by ants, dust, or application of persistant broad-spectrum insecticides.

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Foliage Sprays. Horticultural oil is eggs begin hatching, scale crawlers Systemic Insecticides. Systemic effective in spring or summer on get stuck on the tapes and appear as insecticides are absorbed and moved deciduous plants when sprayed soon yellow or orange specks. Spray after within plants. If the plant is infested after most crawlers have emerged. Late crawler production has peaked and with a scale species susceptible to spring and summer are also the times the number trapped each week has systemic insecticide, systemics are to spray avocado, citrus, and many definitely declined, which is soon after particularly useful where it is not other broadleaf evergreens. Foliage- most crawlers have settled. For more practical to spray because plants are season application requires more spray information on sticky tape monitoring, large or spray may drift to unintended volume on deciduous plants than a consult Pests of Landscape Trees and areas. Depending on the product, dormant treatment because leaves Shrubs, listed in References. systemic insecticide may be applied as well as bark must be thoroughly by spraying foliage, injection or covered. Spring or summer sprays In addition to narrow-range oil, implantation into trunk vascular tissue, should thoroughly cover plant parts insecticidal soap or a mixture of oil or applying on or into soil beneath where most scales occur (typically trees and shrubs, where the insecticide and soap can be sprayed. Carbamate twigs and the underside of leaves) is absorbed by roots. insecticides (carbaryl or Sevin), and be well timed to occur when most organophosphates (e.g., malathion), scales are crawlers or young nymphs, A soil application of the systemic and pyrethroids (e.g., bifenthrin the most susceptible stages. insecticide imidacloprid can provide and cyfluthrin) are other contact season-long control of soft scales insecticides registered for scale control. To effectively time a spray of leafy and certain other species such as However, these more persistent plants, use traps made of double-sided European elm scale. Imidacloprid is sticky tape to determine when crawlers insecticides cause greater disruption not effective on armored scales and are hatching. Before crawlers begin of biological control than oil or soap certain other species such as cottony to emerge in spring, tightly encircle because persistent residues continue to cushion scale. Imidacloprid is available several infested twigs or branches kill or intoxicate beneficial insects and to both homeowners (Bayer Advanced with transparent tape that is sticky mites migrating in after the application. Garden Tree & Shrub Insect Control) on both sides (this tape is available It is also best to avoid the more and professional applicators (Merit and at stationery stores). Change the persistent sprays because of problems others). Imidacloprid can be effective tapes approximately once a week and from their runoff into urban surface when applied to soil during late winter examine the tapes with a hand lens water and contaminating municipal to early spring or before rainfall or to identify the crawlers. Once scale wastewater. irrigation are expected to facilitate root

Figure 5. When applying systemic pesticides to trees, make an application to soil whenever possible as directed on product labels instead of injecting or implanting trunks with pesticides. Injecting or implanting trunks injures trees and can introduce or facilitate entry of plant pathogens.

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TABLE 2. Some Common Soft Scales (Coccidae), Their Impact in California, and the Principal Hosts.

Common Name (Scientific Name) Susceptible Hosts and Impact Hosts Usually Not Damaged

black scale ( oleae) sometimes annoyingly abundant aspen, bay, citrus, cottonwood, coyote bush, holly, away from the and if ant- maple, mayten, oleander, olive, palm, pear, pepper tended tree, pistachio, poplar, privet, stone fruit, strawberry tree, walnut brown soft scale ( hesperidum) annoyingly abundant if ant-tended aspen, avocado, citrus, cottonwood, holly, manzanita, palm, poplar, stone fruit, strawberry tree, willow calico scale () liquidambar sometimes damaged box elder, maple, stone fruit, walnut citricola scale (Coccus citrus and hackberry sometimes elm, pomegranate, walnut pseudomagnoliarum) damaged in Central Valley; biologically controlled in Southern California

European fruit lecanium, also called annoying abundant sometimes alder, almond, aspen, cottonwood, elm, grape, pear, brown apricot scale ( pistachio, poplar, stone fruit, toyon, walnut corni) frosted scale (Parthenolecanium walnut sometimes damaged ash, birch, elm, laurel, , pistachio, rose, pruinosum) sycamore green shield scale () all plants with this scale are aralia, begonia, camellia, croton, eugenia, gardenia, quarantined, under eradication or hibiscus, laurel fig or Indian laurel (Ficus retusa), regulatory control pepper tree, pittosporum, plumeria, Schefflera irregular pine scale (Toumeyella pinicola) Monterey pine infested, mostly in other pines Bay Area Kuno scale (Eulecanium kunoense) stone fruit sometimes damaged, cotoneaster, pyracantha, rose, walnut especially plum tuliptree scale (Toumeyella liriodendri) deciduous magnolias and tuliptree gardenia, linden (yellow poplar) highly susceptible wax scales, including barnacle and annoyingly abundant sometimes California bay laurel, citrus, coyote bush, holly, Chinese wax scales ( spp.) on Escallonia, gardenia, Geijera Mahonia, pepper tree parviflora, and mayten

TABLE 3. Some Common Scales in Other Families, Their Importance in California, and the Principal Hosts.

Common Name (Scientific Name) Susceptible Hosts and Impact Hosts Usually Not Damaged

cottony cushion scale1 ( purchasi, family Cocculus laurifolius highly citrus, nandina, pittosporum2 Margarodidae) susceptible, biologically controlled on other hosts

European elm scale (Gossyparia spuria, Eriococcidae) American and Chinese elms other elms especially susceptible

oak pit scales3 ( spp., Asterolecaniidae) Quercus lobata, Q. douglasii, and other oaks Q. rober highly susceptible

sycamore scale4 (Stomacoccus platani, family London plane and sycamore — Margarodidae) susceptible 1 See Pest Notes: Cottony Cushion Scale, UC ANR Publication 7410 2 Cottony cushion scale can harm “Hosts Usually Not Damaged” if natural enemies are disrupted, such as by application of certain persistent insecticides. 3 See Pest Notes: Oak Pit Scales, UC ANR Publication 7470 4 See Pest Notes: Sycamore Scale, UC ANR Publication 7409

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absorption of the insecticide. Summer trunks (Figure 5). It is difficult to place Geisel, P., and E. Perry. 2004. Pest application to stressed, heavily infested insecticide into trunks at the proper Notes: Oak Pit Scales. UC Statewide IPM trees is less likely to be effective and is depth. Also, unsterilized injection tools Program. Oakland: Univ. Calif. Agric. not recommended. contacting internal parts of multiple Nat. Res. Publ. 7470. Also available plants may mechanically spread certain online at www.ipm.ucdavis.edu. Certain other systemic insecticides are plant pathogens, including bacteria , R. J. 1982. Color-Photo and Host Keys also available, but only to professional (e.g., slime flux or wetwood), fungi to the Armored Scales of California. Scale applicators. For example, dinotefuran (e.g., vascular wilt pathogens), and and Whitefly Key #5. Sacramento: Calif. (Safari) is a neonicotinoid (in the same viruses. The physical act of penetrating Dept. Food Agric. chemical group as imidacloprid) that trunks during injections injures plants. Gill, R. J. 1982. Color-Photo and Host Keys can be sprayed onto foliage or applied Especially avoid methods that cause to the Soft Scales of California. Scale and large wounds, which may lead to wood onto soil or through certain irrigation Whitefly Key #4. Sacramento: Calif. decay. Do not inject or implant trunks systems, especially to control cycad Dept. Food & Agric. scale and soft scales. more than once a year. Gill, R. J. 1988-1997. The Scale Insects of California Parts 1–3. Sacramento: Calif. Injecting Trunks. When using systemics, REFERENCES Dept. Food & Agric. consider making a soil application Dreistadt, S. H., J. K. Clark, and M. L. whenever possible instead of spraying Flint. 2004. Pests of Landscape Trees and Grafton-Cardwell, E. E. 2003. Pest foliage or injecting or implanting Shrubs: An Integrated Pest Management Notes: Cottony Cushion Scale. UC Guide, UC Statewide IPM Program. For more information contact the University Statewide IPM Program. Oakland: Univ. Oakland: Univ. Calif. Agric. Nat. Res. of California Cooperative Extension in your county. Calif. Agric. Nat. Res. Publ. 7410. Also See your telephone directory for addresses and Publ. 3359. available online at www.ipm phone numbers. .ucdavis.edu AUTHORS: S. H. Dreistadt, UC Statewide IPM Flint, M. L. 1998. Pests of the Garden Program, Davis; J. G. Morse, Entomology, UC Riv- and Small Farm: A Grower’s Guide to Klotz, J., and M. Rust. 2005. Pest Notes: erside; P. A. Phillips, UC Statewide IPM Program, Using Less Pesticide. UC Statewide IPM Ventura Co.; R. E. Rice, Entomology, emeritus, Ants. UC Statewide IPM Program. Program. Oakland: Univ. Calif. Agric. Kearney Agricultural Center, Parlier Oakland: Univ. Calif. Div. Agric. Nat. Nat. Res. Publ. 3332. TECHNICAL EDITOR: M. L. Flint Res. Publ. 7411. Also available online at COORDINATION & PRODUCTION: P. N. Galin www.ipm.ucdavis.edu ILLUSTRATIONS: Fig. 1: V. Winemiller; Fig. 2: D. Flint, M. L., and S. H. Dreistadt. 1998. Kidd; Fig. 3: S. H. Dreistadt; Fig. 4: adapted from Natural Enemies Handbook: The Illustrated H. J. Quayle. 1938. Insects of Citrus and other UC Statewide IPM Project. 2000. Pest Guide to Biological . UC Subtropical Fruits. Ithaca, NY: Comstock; Fig. 5: Notes: Sycamore Scale. Oakland: Univ. Statewide IPM Program. Oakland: adapted from S. H., Dreistadt, J. K. Clark, and Calif. Agric. Nat. Res. Publ. 7409. Also M. L. Flint. 2004. Pests of Landscape Trees and Univ. Calif. Agric. Nat. Res. Publ. 3386. available online at www.ipm.ucdavis Shrubs: An Integrated Pest Management Guide. ❖ UC Statewide IPM Program. Oakland: Univ. Calif. .edu Agric. Nat. Res. Publ. 3359 WARNING ON THE USE OF CHEMICALS Produced by IPM Education & Publications, Pesticides are poisonous. Always read and carefully follow all precautions and safety recommendations UC Statewide IPM Program, University of given on the container label. Store all chemicals in the original labeled containers in a locked cabinet or shed, California, Davis, CA 95616-8620 away from food or feeds, and out of the reach of children, unauthorized persons, pets, and livestock. This Pest Note is available on the Pesticides applied in your home and landscape can move and contaminate creeks, lakes, and rivers. Confine chemicals to the property being treated. Avoid drift onto neighboring properties, especially gardens World Wide Web (www.ipm.ucdavis.edu) containing fruits or vegetables ready to be picked. Do not place containers containing pesticide in the trash or pour pesticides down sink or toilet. Either use the pesticide according to the label or take unwanted pesticides to a Household Hazardous Waste Collection site. Contact your county agricultural commissioner for additional information on safe container disposal and for the location of the Household Hazardous Waste Collection site nearest you. Dispose of empty containers by following label directions. Never reuse or burn the containers or dispose of them in such a manner that they may contaminate water supplies or natural waterways. This publication has been anonymously peer reviewed for technical accuracy by University of Cali- The University of California prohibits discrimination or harassment of any person on the basis of race, fornia scientists and other qualified professionals. This color, national origin, religion, sex, gender identity, pregnancy (including childbirth, and medical condi- review process was managed by the ANR Associate tions related to pregnancy or childbirth), physical or mental disability, medical condition (cancer-related Editor for Pest Management. or genetic characteristics), ancestry, marital status, age, sexual orientation, citizenship, or status as a To simplify information, trade names of products covered veteran (covered veterans are special disabled veterans, recently separated veterans, Vietnam have been used. No endorsement of named products era veterans, or any other veterans who served on active duty during a war or in a campaign or expedi- is intended, nor is criticism implied of similar products tion for which a campaign badge has been authorized) in any of its programs or activities. University that are not mentioned. policy is intended to be consistent with the provisions of applicable State and Federal laws. Inquiries This material is partially based upon work supported by regarding the University’s nondiscrimination policies may be directed to the Affirmative Action/Staff the Extension Service, U.S. Department of Agriculture, Personnel Services Director, University of California, Agriculture and Natural Resources, 300 Lakeside under special project Section 3(d), Integrated Pest Drive, 6th Floor, Oakland, CA 94612-3550, (510) 987-0096. Management.

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