Rhododendron

Azalea Bark Scale: Apply horticultural spray oil as a dormant treatment. Crawlers may be managed with acephate, azadirachtin (Ornazin 3% EC only), buprofezin, carbaryl, chlorpyrifos (DuraGuard ME and Dursban 50W only), cyfluthrin, cyfluthrin and imidacloprid, deltamethrin, dinotefuran, horticultural oil, hydrophobic extract of neem oil, imidacloprid, insecticidal soap, lambda-cyhalothrin (Battle GC, Demand CS, Scimitar CS, Scimitar GC, and Scimitar WP only), malathion, methidathion, and thiamethoxam. Marathon 1% G and Marathon 60 WP are labeled for use only on plants grown in containers, flats, benches, or beds.
Management Hints: Select and apply horticultural spray oil according to label directions. Crawlers begin to hatch from eggs in June. Repeat applications may be needed. (p. 336)

Black Vine Weevil (Taxus weevil): Formulations of acephate, azadirachtin, Beauveria bassiana, bifenthrin (Bifenthrin Pro Multi-Insecticide, Onyx Insecticide, Talstar F, Talstar Lawn & Tree Flowable, Talstar GC Flowable, Talstar Nursery Flowable, and TalstarOne Multi-Insecticide only), chlorpyrifos (Dursban 50W only), cyfl uthrin (Tempo SC Ultra, Tempo Ultra WP, and Tempo Ultra WSP only), cyfluthrin and imidacloprid, fenpropathrin, lambda-cyhalothrin, permethrin (Astro Insecticide and Permethrin Pro only), pyrethrins and piperonyl butoxide, and tau-fluvalinate are labeled to manage adults. Acephate Pro 75, Acephate Pro 75 WSP, Furadan 4F, and Orthene Turf, Tree, & Ornamental Spray are labeled to be applied as a soil drench (container grown nursery stock only). Marathon 1% G and Marathon 60 WP are labeled for use only on plants grown in containers, flats, benches, or beds. Merit 2.5 G is labeled for use on ornamental shrubs and small trees in outdoor landscapes and interior plantscapes against black vine weevil larvae in soil. Merit 2, Merit 75 WP, and Merit 75 WSP are labeled for black vine weevil larvae and are for use only in and around industrial and commercial buildings and residential areas. Talstar Nursery Granular is labeled for soil incorporation into potting media used in containerized plantings of ornamental trees, shrubs, plants, flowers, conifers, and Christmas trees. The use of insect-parasitic nematodes applied as soil drenches in container-grown plant material may be effective in reducing larval populations of this pest. Follow label directions for all methods of application and stage of insect to treat.
Management Hints: Spray foliage and surface to manage adults in May and June. Soil drenches can be applied from July to mid-October. Follow all label directions. (p. 240)

Cottony Azalea Scale: Apply horticultural spray oil as a dormant treatment. Formulations of acephate, azadirachtin (Ornazin 3% EC only), buprofezin, carbaryl, chlorpyrifos (DuraGuard ME and Dursban 50W only), cyfluthrin, cyfluthrin and imidacloprid, deltamethrin, dinotefuran, horticultural oil, hydrophobic extract of neem oil, imidacloprid, insecticidal soap, lambda-cyhalothrin (Battle GC, Demand CS, Scimitar CS, Scimitar GC, and Scimitar WP only), malathion, methidathion, and thiamethoxam are labeled for crawler management. Marathon 1% G and Marathon 60 WP are labeled for use only on plants grown in containers, flats, benches, or beds.
Management Hints: Select and apply horticultural spray oil according to label directions. Crawler sprays should be applied from June through early July. Repeat applications may be necessary. (p. 342)

Leafhoppers: Formulations of acephate, acetamiprid, azadirachtin, bifenthrin (Bifenthrin Pro Multi-Insecticide, Onyx Insecticide, Talstar F, Talstar Lawn & Tree Flowable, Talstar GC Flowable, Talstar Nursery Flowable, and TalstarOne Multi-Insecticide only), buprofezin, carbaryl, chlorpyrifos, cyfluthrin, cyfluthrin and imidacloprid, deltamethrin, disulfoton, fenpropathrin, hydrophobic extract of neem oil, imidacloprid, insecticidal soap, lambda-cyhalothrin (Battle GC, Demand CS, Scimitar CS, Scimitar GC, and Scimitar WP only), permethrin, phosmet, pyrethrins and piperonyl butoxide, tau-fluvalinate, and thiamethoxam are labeled for leafhopper management.
Management Hints: Treat when leafhoppers are first noticed and repeat as necessary according to label directions. An infestation of first generation redbanded leafhopper should be managed during late April through early May, and second generation should be treated during mid- to late July. (p. 418)

Mealybugs: Formulations of acetamiprid, azadirachtin, Beauveria bassiana, bifenthrin (Bifenthrin Pro Multi-Insecticide, Onyx Insecticide, Talstar F, Talstar Lawn & Tree Flowable, Talstar GC Flowable, Talstar Nursery Flowable, and TalstarOne Multi-Insecticide only), buprofezin, carbaryl, chlorpyrifos, cyfluthrin, cyfluthrin and imidacloprid, deltamethrin, dinotefuran, fenpropathrin, horticultural oil, hydrophobic extract of neem oil, imidacloprid, insecticidal soap, lambda-cyhalothrin, malathion, permethrin (Astro Insecticide and Permethrin Pro only), phosmet, pyrethrins and piperonyl butoxide, pyriproxyfen, and thiamethoxam are labeled for mealybug management. Marathon 1% G and Marathon 60 WP are labeled for use only on plants grown in containers, flats, benches, or beds. Talstar Nursery Granular is labeled for soil incorporation into potting media used in containerized plantings of ornamental trees, shrubs, plants, flowers, conifers, and Christmas trees.
Management Hints: These insects overwinter as nymphs on the host plant. Females lay eggs in loose, white, waxy ovisacs on the lower leaf surface. Nymphs can be managed when they begin feeding in the spring. Repeat applications may be needed.

Rhododendron Borer: Formulations of bifenthrin (Onyx Insecticide only), chlorpyrifos (Dursban 50W only) and permethrin (Astro Insecticide and Permethrin Pro only) are labeled for borer management.
Management Hints: Clearwing borer sex pheromone traps can be used to pinpoint adult emergence to assist in proper timing of sprays. Treat trunk and larger twigs from mid-May through early June. Repeat applications may be needed. The first insecticide application should be made 7 to 10 days after the first male is captured in a pheromone trap. Prune and destroy wilting branches in late summer.
(p. 258)

Rhododendron Gall Midge: Formulations of carbaryl, cyfluthrin, deltamethrin, lambda-cyhalothrin (Battle GC, Demand CS, Scimitar CS, Scimitar GC, and Scimitar WP only), pyrethrins and piperonyl butoxide, and spinosad (for dipterous gall midges) are labeled for management of midges.
Management Hints: Rhododendron catawbiense and its hybrids and Rhododendron maximum are attacked by this gall midge. Distorted foliage is a symptom of gall formation caused by this pest. Peak emergence of this species occurs during full flower bloom or as leaf buds begin to swell. Eggs are laid on the lower leaf surface as soon as the foliage is free from bud scales. Apply registered formulations during mid- to late May. Repeat applications may be necessary because rhododendrons may produce second and occasionally third flushes of plant growth that may result in two additional generations of this gall midge. (p. 470)

Rhododendron Lace Bug: Formulations of acephate, Beauveria bassiana (BotaniGard ES only), bifenthrin (Bifenthrin Pro Multi-Insecticide, Onyx Insecticide, Talstar F, Talstar Lawn & Tree Flowable, Talstar GC Flowable, Talstar Nursery Flowable, and TalstarOne Multi-Insecticide only), carbaryl, chlorpyrifos (Dursban 50W only), cyfluthrin, cyfluthrin and imidacloprid, deltamethrin, disulfoton, fenpropathrin, horticultural oil, imidacloprid, insecticidal soap, lambdacyhalothrin (Battle GC, Demand CS, Scimitar CS, Scimitar GC, and Scimitar WP only), malathion, permethrin, pyrethrins and piperonyl butoxide, and thiamethoxam are labeled for lace bug management. Marathon 1% G and Marathon 60 WP are labeled for use only on plants grown in containers, flats, benches, or beds.
Management Hints: Treat when lace bugs are first seen in the spring. A second generation usually is active from late July through August. (p. 424)

Rhododendron Stem Borer: Formulations of azadirachtin (Azatin XL Plus only), chlorpyrifos (Dursban 50W only) are labeled for borer management.
Management Hints: Larvae hatch from eggs deposited by females in late June through early July. Apply registered insecticides against emerging adults from mid- to late June before females deposit eggs under the epidermis between girdled out areas of the host plant. Prune and destroy wilting branches. (p. 288)

Southern Red Mite: Apply horticultural spray oil as a dormant treatment. Formulations of abamectin, bifenazate, bifenthrin (Bifenthrin Pro Multi-Insecticide, Onyx Insecticide, Talstar F, Talstar Lawn & Tree Flowable, Talstar GC Flowable, Talstar Nursery Flowable, and TalstarOne Multi-Insecticide only), chlorpyrifos, deltamethrin, disulfoton, etoxazole, fenbutatin-oxide, fenpropathrin, fenpyroximate, hexythiazox, horticultural oil, hydrophobic extract of neem oil, insecticidal soap, lambda-cyhalothrin, malathion, oxydemeton-methyl, pyridaben, spinosad, spiromesifen, and tau-fluvalinate are labeled for mite management.
Management Hints: Treat in May before populations start to increase. (p. 475)

Townsend Scale: Crawlers may be managed with acephate, azadirachtin (Ornazin 3% EC only), buprofezin, carbaryl, chlorpyrifos (DuraGuard ME and Dursban 50W only), cyfluthrin, cyfluthrin and imidacloprid, deltamethrin, dinotefuran, horticultural oil, hydrophobic extract of neem oil, insecticidal soap, lambda-cyhalothrin (Battle GC, Demand CS, Scimitar CS, Scimitar GC, and Scimitar WP only), and methidathion.
Management Hints: Select and apply horticultural spray oil according to label directions. Treat first generation crawlers from mid-May through June. Second generation crawlers should be treated during mid-July through mid-September. Repeat applications may be needed.

Twobanded Japanese Weevil: Formulations of acephate, Beauveria bassiana, bifenthrin (Onyx Insecticide, Talstar GC Flowable, and Talstar Lawn & Tree Flowable only), cyfluthrin and imidacloprid, lambda-cyhalothrin (Battle GC, Demand CS, Scimitar CS, Scimitar GC, and Scimitar WP only), permethrin (Astro Insecticide and Permethrin Pro only), and pyrethrins and piperonyl butoxide are labeled for management of adult weevils.
Management Hints: This brown weevil feeds during the day. Marginal notching of new foliage is a symptom of adult feeding. Treat infested plants when new foliage has notched margins during early July through August. (p. 244)

Whitefly: Formulations of abamectin, acetamiprid, azadirachtin, Beauveria bassiana, bifenthrin (Bifenthrin Pro Multi-Insecticide, Onyx Insecticide, Talstar F, Talstar Lawn & Tree Flowable, Talstar GC Flowable, Talstar Nursery Flowable, and TalstarOne Multi-Insecticide only), buprofezin, chlorpyrifos (Dursban 50W only), cyfluthrin, cyfluthrin and imidacloprid, disulfoton, horticultural oil, hydrophobic extract of neem oil, imidacloprid, insecticidal soap, lambda-cyhalothrin, malathion, novaluron, permethrin, pymetrozine, pyrethrins and piperonyl butoxide, pyridaben, spiromesifen, tau-fluvalinate, and thiamethoxam are labeled for whitefly management. Marathon 1% G and Marathon 60 WP are labeled for use only on plants grown in containers, flats, benches, or beds.
Management Hints: Treat when whitefl ies are fi rst noticed. Repeat applications may be needed. (p. 318)

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