The cottony maple scale is most easily recognized by the characteristic egg masses on twigs and branches. Common Insects of Japanese maple trees. Spots arise in late spring or early summer after leaves attain full size. Both soft and armored scales can be controlled by a soil drench with dinotefuran . Like aphids, soft scales, such as Pulvinaria spp., also excrete honeydew. Phyllosticta leaf spot of maple (Phyllosticta cotoneastri).Paul Bachi, Bugwood.org. Also, they stop the sap from flowing properly within the tree. A certified arborist should be contacted if chemical control is needed. Eggs masses are conspicuously white and cottony in appearance. A pest that can also attack agricultural crops, Potato leafhoppers can be pests of maples in nursery production. For more information, contact the Clemson Home & Garden Information Center. Scorching due to dry soil may be overcome by proper watering. 2Horticultural oil may injure Japanese, amur, and red maples. 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. Tar spots are among the most showy and least damaging foliar diseases. The open wound can be treated with wound paint prior to covering with soil. They are usually seen on leaves, twigs, or bark. They feed on sap by piercing the leaf, stem, or branch with their mouthparts and sucking. 1). 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. Table 1. Your tree should rebound by mid-July; maple trees are generally very hardy. Most borer activity occurs in areas of existing cankers. 04/17/2020. Some are flat and appear like scales stuck to a plant, while others appear like white cottony masses. Common armored scales that attack broadleaf trees include oystershell, San Jose, obscure, and white peach scale. Citrus Thrips are tiny orange, yellow, or even black insects that can attack trees at any age. Aphids: Aphids are soft-bodied insects that range from 1/16 to ⅜ inch long. Controlling this pest on a large tree using chemicals is expensive and often not practical. Nymphs are smaller but look similar to adults otherwise. Marjan Kluepfel, Former HGIC Horticulture Information Specialist, Clemson UniversityJanet McLeod Scott, Former Horticulture Information Specialist, Clemson UniversityJames H. Blake, EdD, Extension Associate/Adjunct Professor, Dept. 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. If a tree is small, the homeowner can handpick and destroy leaves before exit holes form to allow the release of the pest. 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). Scorch symptoms are light brown or tan dead areas between leaf veins or around the leaf margins. They are also found throughout the Eastern United States. Japanese maple trees are normally not affected by many insects. These miscreants can be either beetles or clearwing moths, but the end result is the same. Note: Pollinating insects, such as honey bees and bumblebees, can be adversely affected by the use of pesticides. Follow all directions, precautions and restrictions that are listed. There are 2 generations a year in Maryland. Wood boring insects typically attack already damaged or unhealthy trees. The lower surface of a leaf beneath a large tar spot turns brown, but the surface beneath speckled tar spots remains yellow. Tâ¦ A response to an undesirable soil contaminant, such as salt (applied to roads for wintertime ice control), accumulation of fluorides in containerized soil mixes with perlite, or high levels of phosphate fertilizers. Armored scales, such as Melanaspis tenebricosa, do not excrete honeydew, as they feed differently than the soft scales. They often produce a honeydew which attracts another Japanese maple problem, sooty mold . The symptoms are most noticeable in late summer to early fall, following extended periods of drought. To control Citrus Thrips spray the tree with Garden Insect Spray with Spinosad. Since some insect pests respond only to very specific treatment, it is critical to know what you are protecting your shrubs and trees against. Insects, in some cases, have the potential to rot and destroy trees. All native ash species are susceptible to attack. Fertilization of the tree after root removal will aid in recovery. These fruiting bodies occur in greater numbers on the upper leaf surface. Both narrow- and broadleaf evergreens are vulnerable to insect attack, sometimes just to an unsightly degree, and sometimes to the point of fatality. Scorch symptoms tell us that one or more of the following factors are affecting the tree: 1. For example, sprays with insecticidal soap, horticultural oil, neem oil extract, spinosad, Bacillus thuringiensis (B.t. website content by L. Townsend and J. Larson website design by P. Dillon copyright © 2017 - Specific insects and infestations take place over a limited area, at a maximum of several thousand acres. Prevention & Treatment: Several natural enemies, such as ladybird beetles (ladybugs) and lacewings feed on aphids. Bacterial Leaf Scorch: This disease is caused by the bacterium Xylella fastidiosa. Copyright © 2020 Clemson UniversityClemson Cooperative Extension | 103 Barre Hall Clemson, SC 29634864-986-4310 | Contact UsHGIC@clemson.edu, Integrated Pest Management (I.P.M.) Spindle galls, however, are usually indicative of mites. Prevention & Treatment: The portion of the root that is girdling the tree should be removed. Colonies of these pests are obvious because of their white, fuzzy appearance. Galls vary greatly in appearance, from wart-like bumps to spindle-shaped protrusions to felt-like patches on the leaf’s surface. This disease is most severe during wet weather. Clemson University Cooperative Extension Service offers its programs to people of all ages, regardless of race, color, gender, religion, national origin, disability, political beliefs, sexual orientation, gender identity, marital or family status and is an equal opportunity employer. This fungus serves as a source of food, and may partially be responsible for the death of the host plant. Spraying three times at two-week intervals with a copper-based fungicide, mancozeb, or triadimefon starting when the leaves begin to unfurl in spring will provide control (see Table 1 for specific products). 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. Their holes are normally round, oval or semicircular and are found in a random pattern on the plant. As a result of their phenomenal ability to reproduce, aphids are very difficult to control with insecticides. As with all pesticides, read and follow all label directions and precautions. Scales vary in appearance depending on age, sex, and species. Heavy infestations over several seasons may kill plants. Caterpillars and beetles make up the largest proportion of chewing insects. Use pesticides only according to the directions on the label. 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