Seagraves and R. Bessin, University of Kentucky. Insects affecting Japanese Maple Trees. Bacterial Leaf Scorch: This disease is caused by the bacterium Xylella fastidiosa. Thrips attack young leaves and juvenile fruit and feed on the citrus tree sap. All recommendations for pesticide use are for South Carolina only and were legal at the time of publication, but the status of registration and use patterns are subject to change by action of state and federal regulatory agencies. Galls typically develop in spring at about the time that leaves are expanding. If you know the name of the tree pest or disease affecting your trees, see the Forestry Commission guidance giving detailed information on specific tree pests or diseasesknown to be present in the UK. Insects Attacking Trees. Like aphids, soft scales, such as Pulvinaria spp., also excrete honeydew. It is caused by dry weather, combined with wind and high temperatures. Multiple treatments may be needed during a season. Spraying three times at two-week intervals with a copper-based fungicide, mancozeb, chlorothalonil, thiophanate methyl, or triadimefon starting when the leaves begin to unfurl in spring will provide control (see Table 1 for specific products). Generally, trees can bounce back from an attack of these defoliators, though repeat infestation will weaken a tree and can eventually kill it by starving it of energy. An Equal Opportunity University | Woolly alder aphid (Paraprociphilus tessellatus) is gray to black in color. 5Neem oil may cause injury to Japanese maples. Specific insects and infestations take place over a limited area, at a maximum of several thousand acres. Often the distinctive shape allows for identification of the pest. Other chewing insects attack the fruit. Scale insects are somewhat predatory and attack … This scale primarily attacks azalea and rhododendron but has also been found on andromeda, maple, arborvitae, willow, poplar, and hackberry. The size of the tree, the need for specialized equipment, and the cost may prohibit this approach. The moth was introduced into the United States in 1862. Then, during late summer, raised, shining black, tar-like dots develop within the yellow spots on the upper leaf surfaces. Especially when they see all the small bugs underneath the loose bark. Most borer activity occurs in areas of existing cankers. document.write(year) Emerald ash borer (Agrillus planipennis) adults are distinctive dark metallic green beetles that are about 1/2 long and about 1/8 inch wide. Tree borers are a group of insects that lay their eggs on or inside of trees, where the young larvae eat their way through living tissues. A pest that can also attack agricultural crops, Potato leafhoppers can be pests of maples in nursery production. As an alternative, dinotefuran or imidacloprid can be applied as a drench around the root zone of aphid-infested plants and is systemically taken up by the root system for insect control (see Table 1 for specific products). Insecticides & Fungicides for Maple Insect Pest & Disease Control. The way that insects attack trees is by defoliating them. Scale insects are a sucking insect that extract plant sap from the host plant. Apply materials when crawlers appear and repeat in 10 days. In the young larval stage, carpenterworm caterpillars reach a length of 2 to 3 inches, with a display of white/green bodies and dark heads. Physiological leaf scorch is the most common. Often these trees are less than four inches in diameter. Prevention & Treatment: Several natural enemies, such as ladybird beetles (ladybugs) and lacewings feed on aphids. Greenstriped mapleworms, Dryocampa rubicunda, feed on maple trees in summer. Colonies of these pests are obvious because of their white, fuzzy appearance. If spraying is required, always spray late in the evening to reduce the direct impact on pollinating insects. Woolly alder aphid (Paraprociphilus tessellatus).Bob Lepak, Bugwood.org. Permethrin may be used as a trunk and scaffold limb spray beginning in March (see Table 1 for specific products). When trees do not get enough water they will scorch. Fertilization and watering may help to reduce the disease. for Aphids, College of Agriculture, Forestry and Life Sciences, Centipedegrass Yearly Maintenance Program, Ferti-lome Broad Spectrum Insecticide Concentrate, Bayer Advanced Vegetable & Garden Insect Spray Concentrate; & RTS, Ortho Tree & Shrub Insect Control Ready to Use Granules, Bayer Bio Advanced 12 Month Tree & Shrub Insect Control Landscape Formula, Spectracide Triazicide Insect Killer for Lawn & Landscapes Concentrate, Bonide Neem Oil Fungicide, Miticide, Insecticide Concentrate, Bonide Eight Insect Control Vegetable Fruit & Flower Concentrate, Cleary’s 3336-WP Turf & Ornamental Fungicide. Tar Spot: Tar spot is caused by the fungus Rhytisma acerinum. ‘Autumn Flame’, ‘Tilford’, and ‘Gerling’ red maple varieties are relatively resistant to leaf spot. They may be green, yellowish, pink, gray or black. On the leaves, spots appear with pale yellow centers and purple borders. Presumably, the symptoms develop because of water stress within the water conducting vessels. The Top Hardwood Tree Killing Insects. They are usually seen on leaves, twigs, or bark. Spinosad may cause injury to Japanese Maples. Now, however, the results of a summer's worth of sap feeding by maple aphids is quite apparent as damaged leaves are falling from maple trees and accumulating on the ground below. var year = today.getFullYear() Granulate ambrosia beetle (Xylosandrus crassiusculus) larvae (Motschulsky, 1866).Will Hudson, University of Georgia. Since the beetles do not consume the host plant material, dinotefuran and imidacloprid systemic soil treatments are ineffective. Roud mites only eat maple leaves that are still developing. They often produce a honeydew which attracts another Japanese maple problem, sooty mold . Once the gall forms, the pest is protected inside the structure. Scorch symptoms are light brown or tan dead areas between leaf veins or around the leaf margins. Woodpecker damage is sometimes confused with that of wood-boring beetles; however, woodpecker damage will not produce frass. Tar spot of maple (Rhytisma acerinum).Andrej Kunca, Bugwood.org. Charlotte Gerber (author) from upstate New York on June 11, 2010: Hi Jeremy, Maples have had a really tough year, and many had it rough last year as well. They are also found throughout the Eastern United States. Both narrow- and broadleaf evergreens are vulnerable to insect attack, sometimes just to an unsightly degree, and sometimes to the point of fatality. This disease is more common in the forest, but may be seen in some landscape situations. For example, sprays with insecticidal soap, horticultural oil, neem oil extract, spinosad, Bacillus thuringiensis (B.t. 1). The larvae feed on the inner bark of ash trees from June through October, disrupting the tree's ability to transport water and nutrients. website content by L. Townsend and J. Larson  website design by P. Dillon   copyright © 2017 - Leaving one aphid alive can result in the production of a new colony very quickly. The open wound can be treated with wound paint prior to covering with soil. Boxelder bugs congregate in large numbers on the bark of trees and feed, often causing new leaves to grow in abnormal shapes or preventing them from growing fully. Once a tree has been attacked, it becomes more attractive to further attack. Other trees susceptible to damage are apple, ash, birch, crabapple, dogwood, oak, elm, hickory, and redbud. As a result of the honeydew, sidewalks and cars become sticky. This fungus serves as a source of food, and may partially be responsible for the death of the host plant. The mites rapidly reproduce and eat new leaves by forming galls. Each insect or mite produces its own distinctive gall shape. They’re rarely found on Japanese maple, but some readers state they’ve seen this pest. The western pine beetle, Dendroctonus brevicomis, can aggressively attack and kill ponderosa and Coulter pine trees of all ages. This information is supplied with the understanding that no discrimination is intended and no endorsement of brand names or registered trademarks by the Clemson University Cooperative Extension Service is implied, nor is any discrimination intended by the exclusion of products or manufacturers not named. Anthracnose: This disease is caused by the fungus Aureobasidium apocryptum. In the spring spores are produced and dispersed to the new leaves of susceptible trees. ), or botanical oils can help control many small insect pests and mites that affect garden and landscape plants. I suggest keeping an eye on the tree. Chemical treatments are rarely needed and must be repeated indefinitely. Research indicates that spraying the infested trunks with permethrin may cause the beetles to leave the galleries they have already created. It requires alder and silver maple to complete its life cycle. Controlling this pest on a large tree using chemicals is expensive and often not practical. Many insects can attack your poplar tree, but the most common pests are scale insects, mealybugs and cottony cushion scales, poplar petiole gall … Keep your maple healthy by appropriate watering and fertilizing for the species or cultivar, pruning dead or damaged limbs and protecting the trunk from injury by lawn equipment. Visible symptoms include wilted foliage, as well as the toothpick-like strands of boring dust (frass) that protrude from these small, pencil-lead size holes. Insects with the potential to damage trees choose only one to a handful of species to attack. Black fruiting bodies of the fungus develop in a circle in the centers of the spots. Ocellate gall midge (Acericecis ocellaris).Lacy L. Hyche. Although the beetles seem to prefer maples, they also attack birch, buckeye, horse-chestnut, poplar, willow, elm and ash trees. If it is an exotic insect like Asian Longhorned Beetle, the proper authorities need to know so they can try to prevent them from spreading. There are many families of insects to identify. Wood boring insects typically attack already damaged or unhealthy trees. Aphids: Aphids are soft-bodied insects that range from 1/16 to ⅜ inch long. Aphids are small insects about the size of a ball point pen tip, they will occasionally be found feeding on new tender growing tips of Japanese maple trees. Bacterial leaf scorch of maple (Xylella fastidiosa).John Hartman, Bugwood.org. Read and follow all directions on the label. Insecticides kills the beneficial insects that attack broadleaf shrubs include euonymus scale, oystershell, San.... These predators should be removed inch long, gray or black if needed pests... 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