Survey
* Your assessment is very important for improving the work of artificial intelligence, which forms the content of this project
Download Weeds - Michigan State University
Document related concepts
no text concepts found
Transcript
Weeds Identification Topic 2044 Mr. Christensen Why are weeds weeds? • Weeds are plants out of place. • Reduce crop Yields, compete for water, nutrients and/or light. • Reduce crop quality • Some are poisonous • Host for disease and insects • Degrade aesthetics Weed Characteristics • Produce huge numbers of seeds per plant. • Many are self-pollinated, allowing one single plant to produce thousands of seeds. • Seeds resist decay. • Seeds remain dormant in the soil. • Seeds have several dormancy mechanisms. Weed Characteristics • Seeds can mimic crop seed size and shape. • Leaves and stems adapt to repel grazing animals. • Low growth habit allows weeds to survive in alfalfa fields that are cut three or four times a year. • Avoid control mechanisms. Weed hosts for nematode and insect pests Weed Nightshades Redroot pigweed Common lambs quarters Common lambs quarters Various weeds Host for Colorado potato beetle White mold Root aphids Soybean cyst nematode Aphids that carry barley yellow dwarf virus Impact on Crop Production • Corn yield reduction varies by weed species in 10 feet of crop row 30 giant foxtail—13-14% 27 velvetleaf—21-34% Dry bean yield losses with 30 weeds per 10 feet of crop row Hairy nightshade 45-55% Common ragweed 5-45% Wild proso millet 12-31% Impact on Crop Production • Soybean/weed competition (% reduction) Weeds per 10 ft. Low yield yr High yield yr Cocklebur 1 3 5 13 28 66 Smartweed 6 2 10 11 26 46 Giant foxtail 6 0 2 117 6 17 Life Cycle One Way to Classify Weeds • • • • Summer Annuals Winter Annuals Biennials Perennials-simple and creeping Summer Annuals From Michigan Field Crop Pest Ecology and Management-Michigan State University Extension Bulletin E-2704 Summer Annuals Examples Barnyardgrass Shattercane Wild Oat Large Crabgrass Smooth Crabgrass Giant Foxtail Yellow Foxtail Green Foxtail Fall Panicum Wild-Proso Millet Common Cocklebur Witchgrass Jimsonweed Woolly Cupgrass Common Sunflower Longspine Sandbur Common Ragweed Ladysthumb Pennsylvania Smartweed Giant Ragweed Velvetleaf Wild Buckwheat Common Purslane Ivyleaf Morninglory Pigweed (Redroot,Smooth)Venice Mallow Eastern Black Nightshade Common Lambsquarters Yellow Foxtail Lambsquarters Common Purslane Redroot Pigweed Velvetleaf University of California http://www.ipm.ucdavis.edu/PMG/weedscommon.html Winter Annuals Examples Downy Brome Field Pennycress Virginia Pepperweed Shepherd’s Purse Wild mustard Horseweed Common chickweed Prickly Lettace Henbit From Michigan Field Crop Pest Ecology and Management-Michigan State University Extension Bulletin E-2704 Wild Mustard Common Chickweed Horseweed Shepard’s Purse University of California Virginia Technological University http://www.ipm.ucdavis.edu/PMG/weeds- http://www.ppws.vt.edu/scott/weed_ common.html id/dauca.htm Biennials Examples Yellow Rocket Bull Thistle Common Mullein White Campion Wild Carrot From Michigan Field Crop Pest Ecology and ManagementMichigan State University Extension Bulletin E-2704 Virginia Technological University http://www.ppws.vt.edu/scott/weed_id/dauca.htm Bull Thistle Wild Carrot Common Mullein Virginia Technological University http://www.ppws.vt.edu/scott/weed_id/dauca.htm Perennials Examples Curly Dock Dandelion Quackgrass Yellow Nutsedge Johnsongrass Field Bindweed Canada Thistle From Michigan Field Crop Pest Ecology and ManagementMichigan State University Extension Bulletin E-2704 University of California http://www.ipm.ucdavis.edu/PMG/weeds-common.html Canada Thistle Yellow Nutsedge Quackgrass Curly Dock University of California http://www.ipm.ucdavis.edu/PMG/weeds-common.html Poisonous Plants • House Plants—Hyacinth, Narcissus, Daffodil, Oleander, Dieffenbachia, Rosary Pea, Castor Bean Cornell University-www.ansci.cornell.edu/ Poisonous plants • Flower Garden Plants—Larkspur, Monkshood, Autumn Crocus, Star of Bethlehem, Lily-of-the-valley, Iris, Foxglove, Bleeding Heart Iris Cornell University-www.ansci.cornell.edu/ Star of Bethlehem Poisonous Plants • Ornamental Plants—Daphne, Wisteria, Golden Chain, Laurels, Rhododendrons, Azaleas, Jasmine, Lantana Camara, Yew Jasmine Cornell University-www.ansci.cornell.edu/ Wisteria Poisonous Plants • Vegetable Garden Plants-Rhubarb Rhubarb Cornell University-www.ansci.cornell.edu/ Poisonous Plants • Trees and Shrubs-Wild and cultivated cherries, Oaks, Elderberry, Black Locust Cherries Cornell University-www.ansci.cornell.edu/ Elderberry Poisonous Plants Horse chestnut Black Locust Poison Ivy Poison Oak Poison Sumac Poisonous Plants • Plants in wooded areas-Jack-in-the-Pulpit, Mayapple Moonseed, Mayapple, Mistletoe Misletoe University of California http://www.ipm.ucdavis.edu/PMG/weeds-common.html Cornell University-www.ansci.cornell.edu/ Jack in the Pulpit Poisonous Plants Cornell University-www.ansci.cornell.edu/ Poisonous Plants • Plants in Swamp or moist areas-Water Hemlock Cornell University-www.ansci.cornell.edu/ Poisonous Plants • Plants in Fields-Buttercups, Nightshade, Poison Hemlock, Jimson Weed Belladonna/Nightshade Jimson Weed Cornell University-www.ansci.cornell.edu/ Milkweed Poisonous Plants Pokeweed Cornell University-www.ansci.cornell.edu/ Medicinal Plants Belladonna Dandelion Dill Garlic Hamamelis witch hazel Aloe Vera Arrowroot Basil Jasmine University of California Olive http://www.ipm.ucdavis.edu/PMG/weeds-common.html Radish Rose Cornell University-www.ansci.cornell.edu/ Wormwood Celery Weed Identification Laboratory • Learn to identify 20 common weeds. • Utilize seeds, plant parts, and live specimens.
Related documents