Sanitation Segregate Plants

Transcription

1 Detecting Pests in Systemsbased Pest Management Frank A. Hale Professor Department of Entomology and Plant Pathology Pest Scouting Train and dedicate one person to scout along with one or two backup scouts Choose from your best dedicated employees Often, this will be the same person who does the pesticide applications Equipment Hand lens or Magnifying visor for hands free inspection Clipboard Sticky cards Marking stakes Data forms quantify insect counts and map infestations Initial Inspecting Incoming nursery stock should be inspected at delivery and before unloading Reject loads that contain infected or infested plants Inspect packing material and the inside of the van for hitchhikers such as slugs, snails, ants, fungus gnats and other pests If possible, allow the greenhouse to stand empty for one week before bringing in a new crop Control any weeds in the greenhouse and any around the outside of the structure Sanitation Segregate Plants Segregate incoming plants away from existing nursery stock for at least 60 days during the active growth stage Do not co-mingle new buy-ins with existing stock until you are confident that the buyins are pest-free 1

2 Indicator Plants and Record Keeping Leave 10% of incoming plants untreated by pesticides, so that any disease symptoms and pest infestations can be seen Keep records of all treatments that are applied to infested or diseased plants Routine Pest Scouting All infected or infested plants should be brought to the attention of the nursery manager for diagnosis and corrective action instead of being disposed of by field workers Unusual and unrecognized pests and pathogens should be submitted to diagnostic labs Best Management Plan Employees need to be trained to implement the best management plan or standard operating procedure for pest control at your nursery Greenhouses should be screened to keep insects out and should have double door entry Sticky Card Monitoring Besides physically examining the plants for pests, yellow or blue sticky cards can be used to detect some pests while they are still at low levels Especially thrips Use an integrated pest management/systemsbased pest management program Sticky Cards Detect Thrips adults Winged adult aphids Leafminer fly adults Whitefly adults Male scale adults Moths Fungus gnat adults Shore fly adults Beneficial insects such as green lacewing adults, lady beetle adults, parasitoid wasps and flies, and others Sticky Cards Change sticky cards at least once per week Hang traps vertically about one foot above plant canopy (lay horizontally on potting media surface for fungus gnat adults) Use one sticky card per 1,000 square feet 2

3 Fungus Gnats Monitoring Fungus Gnat Developmental Stages Egg to larva (four instars) to pupa to adult Egg to adult in 12 days (80 F) to 27 days (55 F) Image provided by Home Harvest Garden Supply, Inc. Comparison of Shore Fly to Fungus Gnat Scouting and Monitoring Procedures Count insects and mites on randomly chosen leaves and plants Record the life stages found on a specific plant Record the type and number of insects found on sticky cards Base the need for treatment on pest detection and counts taken Images by Richard K. Lindquist Scouting and Spray Application Records Document Actions A proper systems-based pest management program should be able to provide evidence of pest occurrence and the control actions taken Leafminer Adults and Feeding Marks 3

4 Leafminers Daylily Leafminer Insect Detection The white cast skins from molting aphids can be mistaken for whiteflies or dead aphids Aphids, whiteflies, soft scales, and mealybugs produce honeydew on which sooty mold grows Aphid Life Cycle Drawing provided by Richard K. Lindquist Aphid Parasitoid Wasps Oak Phylloxera Image by Alan Windham, UT 4

5 Whitefly Life Cycle GreenhouseWhitefly Eggs Drawing provided by Richard K. Lindquist Image by K. Gray, Oregon State U. Greenhouse Whitefly Silverleaf Whitefly Pupae Wings held nearly flat across back Empty pupa next to one ready for adult to emerge Oval pupa is dome shaped Oval pupa shaped like a two layer fringed cake Directly above and below by Ken Gray, Oregon State U. Thrips Life Cycle Thrips The carbon dioxide in your breath will cause thrips to move about if you blow into a flower Drawing provided by Richard K. Lindquist 5

6 Thrips Damage Greenhouse Thrips Damage to sweet viburnum Gynaikothrips uzeli, a Thrips, on Ficus benjamina Armored Scale Armored Scale Crawler Japanese Maple Scale Very small, white body Generalist attacks numerous species! cherry, dogwood, Euonymus, holly, hornbeam, Itea, lilac, linden, magnolia, maple, pyracantha, privet, Prunus, redbud, serviceberry, Stewartia, Styrax, yellowwood, & Zelkova Image courtesy of A. Fulcher, UT 6

7 White Peach Scale Japanese Maple Scale Eggs Good coverage is essential when using horticultural oil and other contact insecticides White Peach Scale Soft Scale Apply horticultural oil in February-March (dormant) Target insecticide sprays for crawlers of the three generations in May, July and September Cottony Camellia Scale Mealybug Developmental Stages Egg to adult in 60 days, but varies widely with individual species and temperatures Overwintering adults Common on holly and yew Adult laying eggs Crawlers Eggs in ovisac starting to hatch Egg laying 7

8 Madeira Mealybug Striped Mealybug Image provided by Ron Oetting Miscanthus Mealybug Root Mealybug Seeing more root mealybug with the increased number of perennials being grown Symptoms are slow plant growth, lack of vigor and subsequent death Image by Arnold H. Hara Twospotted Spider Mites A warm season mite that injures over 180 plant species Active from early spring to late fall (when warm) Spruce Spider Mites A cool season mite pest of arborvitae, juniper, false cypress, hemlock, pine, spruce and others Overwinters as adult females in ground litter or on weed hosts low to the ground Thus, horticultural oil sprays of nursery crops during the dormant period will not control twospotted spider mites Active in the spring and late summer-fall Overwinter in the egg stage 8

9 Questions? 9