Introduction To Weed Science And Weed Identification
Introduction to Weed Science andWeed Identification
Definition of a Weed A plant growing where it is not wanted (Oxford Dictionary) Any plant or vegetation, excluding fungi, interfering withthe objectives or requirements of people(European Weed Science Society) A plant that is especially successfulat colonizing and proliferating indisturbed sites
First Steps in Weed Management To effectively manage weeds youshould know:– What weed you are dealing with –correct identification– Consider impact of the weed– Life cycle of the weed Weed biology influences methods andoptimum time for managementstrategies
Weed Classification Morphology– Structure and form Life cycle– How it developsGround ivyYellow foxtailYellow nutsedge
Weed Classification – Morphology Monocotyledon – onecotyledon or oneembryonic leaf– Grasses, sedges, rushes Dicotyledon - twocotyledons– “Broadleaf” plants
Weed Classification – Life Cycle Annuals– Complete their life cyclefrom seed to seed in lessthan 12 monthsGiant foxtailVelvetleafCocklebur
Summer Annuals Seeds germinate in spring Flower in mid to latesummer Produce seed in latesummer or fall, then die Similar growing season tocorn and soybean E.g., lambsquarters,foxtails, crabgrass,purslane, waterhempLambsquartersLarge crabgrass
Winter Annuals Germinate in late summeror fall Dormant over winter Flower and produce seedin mid to late spring Die in summer E.g., shepherd’s purse,chickweed, pennycress,speedwellsPennycressChickweed
Biennials Complete life cycle intwo years Germinate and formbasal rosette first year,remain vegetative andstore food for winterWild carrotMusk thistleWild parsnip
Biennials Flower, produce seed, and dieduring second growing season Need undisturbed soil for atleast two years E.g., musk thistle, wild carrot,wild parsnip, garlic mustardWild carrotMusk thistleWild parsnip
Perennials (herbaceous) Live for more than two years– Simple: produce a taproot,spread only by seed E.g., Dandelion, broadleafplantainBroadleaf plantain– Creeping: can reproduce bybuds, rhizomes, tubers,bulbs, and seed E.g., Quackgrass, nutsedge,leafy spurgeYellow nutsedge
Weed ID - Sources of Information ISU Weed Identification Field GuideReference booksExtension bulletinsMany websites– http://www.wssa.net/Weeds/ID/PhotoGallery.htm– http://plants.usda.gov/ Someone “in the know”– Local experts– Extension offices
What Makes a Weed Successful? Seed characteristics Ability to germinate andgrow in many environments Rapid seedling growth Self-compatibility or easycross-pollination Vigorous vegetativereproduction Ability to tolerateenvironmental stressesProstrate spurgeCanada thistle
Seed Characteristics Longevity of seedLong period of seed productionHigh seed outputAbility to produce seed inadverse conditions Long and short seed dispersalGiant ragweedLambsquarters
Vegetative Reproduction Rhizomes– Underground structures thatproduce new plants E.g., canada thistle, quackgrass Stolons– Above-ground creeping stemsthat root at nodes andproduce new plants E.g., ground ivy (creepingcharlie)QuackgrassGround ivy
Vegetative Reproduction Bulbs, bulblets, tubers– Underground leaf tissuemodified for foodstorage. Produces newplants E.g., wild garlic, yellownutsedgeYellow nutsedge– Aerial bulblets (aboveground) E.g., wild onion, wild garlicWild onion
Vegetative Reproduction Plant reproduction– Each plant part canregenerate anotherplant– When cultivating, theimplement canredistribute them in thefield E.g., Asiatic dayflower,purslaneAsiatic dayflowerPurslane
Dispersal WindAttachment – burs, thorns, stickersDandelionBirds – digestion/excretionArtificial dispersal – “humandispersal”– Soil and compost– Equipment– Plants– Contaminated seedBurdock
Weed Management StrategiesCanada thistleVelvetleafPoison ivyYellow nutsedge
Summary Identify the weed Know the life cycle Use control strategies based onweed species, life cycle, crop, fieldor landscape situation, and theenvironment
Introduction to Weed Science and Weed Identification . Definition of a Weed A plant growing where it is not wanted (Oxford Dictionary) Any plant or vegetation, excluding fungi, interfering with the objectives or requirements of people (European Weed Science Society)
W-253 2018 NORTH DAKOTA WEED CONTROL GUIDE Compiled by: Rich Zollinger Extension Weed Science Contributors: Mike Christoffers Research Weed Science, Weed Genetics Caleb Dalley Research Weed Science, Hettinger R&E Center Greg Endres Extension Area Agronomist, Carrington R&E Center Greta Gramig Research Weed Science, Weed Ecology Kirk Howatt Research Weed Science, Small Grains/Minor Crops
3.2 Chemical Weed Control 10 3.3 Thermal Weed Control 14 3.4 Biological Weed Control 15 4.0 Natural Areas Weed Management 16 4.1 Purpose 16 4.2 Limitations 16 4.3 Study Area 16 4.4 Weed Management Site Prioritisation 18 4.5 Weed Monitoring 20 4.6 Weed Prevention 22 4.7 Weed Control 24 4.8 Partnerships 28 5.0 Parks and Urban Landscaping
A guide to spring weed control Spring weed control in established pasture There are three key steps to effective spring weed control in established pasture - timing, weed identification and product selection. 1. Timing One of the most common mistakes made with spring weed control is spraying too late.
control, weed control, weed control '. Of course there are other important tasks, but weed control is surely one of the most vital! It is important to achieve good weed control in the 1m2 around each seedling. However the amount of ground disturbance should be kept to a minimum as open ground is an invitation to fresh weed establishment.
Introduction Weed management has been identified in many surveys of organic growers and farmers as being their number one problem, often by over 80% of respondents. Good weed management is essential for a successful organic enterprise. However, the amount of detailed information on organic weed . Organic Weed Management: A Practical Guide .
Cultural and mechanical weed control emove light or spotty weed infestations by hand-hoeing or R spot cultivation to prevent spreading weed rhizomes, roots, or seed. hen plowing perennial weeds, take care to prevent trans W - porting and spreading plant parts to other areas of the field. se weed-free planting seed to prevent weed infestations in U
of Pasture Weed Control Controlling weeds shifts site resources to grow more grass. If weeds are present, horses tend to preferentially graze where weed pressure is less. When given a choice, horses will preferentially graze the weed free areas and the amount of grass will decline due to spot grazing and weed competition.
Software Development , Scrum [11] [12], Scrumban [Ladas 2009 and several va-riant methods of agile]. The agile methodology is based on the “iterative enhancement” [13] technique [14]. As a iteration based methodology, each iteration in the agile methodology represents a small scale and selfcontained Software Development Life Cycle - (SDLC) by itself . Unlike the Spiral model [1] , agile .
