Presentation on theme: "Carol Randall USDA Forest Service Forest Entomologist"— Presentation transcript:
1 Carol Randall USDA Forest Service Forest Entomologist Noxious WeedsCarol RandallUSDA Forest Service Forest Entomologist
2 What is a Weed? “A plant out of place.” “A plant whose virtues have not yet been discovered.”“Plants obstructing the activities of man.”“A plant not valued for use or beauty, growing wild and rank, & regarded as cumbering the ground or hindering the growth of superior vegetation.”
3 Noxious vs. Obnoxious Weeds Noxious weeds are designated by a regulatory agency- and by law managers must manage these plantsObnoxious weeds are plants which can invade a site, but which are not considered enough of a threat to merit regulation
4 Why Manage Noxious Weeds? Noxious weeds have the potential to:Destroy wildlife habitat.Reduce recreation opportunities.Displace threatened and endangered species.Reduce plant and animal diversity.Disrupt waterfowl and migratory bird flight patterns and nesting habitats.Cost millions of dollars in treatment and loss of productivity to private land owners.
5 "Noxious weed" means any plant having the potential to cause injury to public health, crops, livestock, land or other property; and which is designated as noxious by the director. (Idaho Code )Have to be designated by lawDirector of the Idaho State Department of Agriculture makes legal designation for IdahoIdaho currently has 64 “noxious” weeds
6 ISDA Criteria for Designating Noxious Weeds It must be present in but not native to IdahoIt must be potentially more harmful than beneficial to IdahoEradication must be economically and physically feasibleThe potential adverse impact of the weed must exceed the cost of control
7 Three Levels of Concern- Idaho’s Noxious Weed List Statewide Early Detection Rapid Response (EDRR) ListStatewide Control ListStatewide Containment ListBrazilian Elodea, Giant Knotweed, Canada Thistle
8 Statewide Early Detection Rapid Response (EDRR) List Theoretically these plants are not well established in IdahoFocus is to identify populations of these weeds and eradicate them"Eradication" means the elimination of a noxious weed based on absence as determined by a visual inspection by the control authority during the current growing seasonEuropean FrogbitPoliceman’s Helmet
14 Something you probably did not know about Idaho… We are one of the most progressive states in the nation when it comes to addressing noxious weeds
15 Idaho’s Statewide Weed Education and Advocacy Groups Idaho Association of Weed Control Superintendents (IAWCS)Idaho Weed Coordinating Committee (IWCC)Idaho Weed Control Association (IWCA)Idaho Weed Awareness Campaign (IWAC)
16 Other Assets: Weed Science Program at the University of Idaho Research Programs at other State Institutes of Higher EducationCooperative Weed Management Areas
17 Cooperative Weed Management Areas (CWMA) Most of Idaho’s land mass iscontained in one of 32 CooperativeWeed Management Areas (CWMA)CWMAs are formed when thelandowners and land managers ofa given area come together andagree to work cooperatively tocontrol weedsCWMAs identify the highest priorityweed control activities for their area,then share resources to get prioritywork done
18 So why is an entomologist talking about weeds? I work closely with county weed superintendents, CWMA’s, and weed researchers on classical weed biological control- or the use of insects to help control weeds
19 Idaho- A Biological Control of Weeds Super Power We have weed biological control researchers at our land grant collegeWe have a statewide biological control coordinator (ISDA/BLM)We have designed and implemented the only statewide biological control of weeds monitoring programWe have a number of statewide groups which cooperate on biological control of weed projects
20 How do you develop a weed treatment strategy Most successful weed management strategies incorporate a number of methods: herbicides, mechanical, cultural, and when appropriate biological control.Use of multiple methods simultaneously is called Integrated Pest Management- or IPM.A good weed treatment strategy relies on realistic management objectives, accurate weed identification and mapping, as well as post treatment monitoring. (“DID IT WORK?”)
21 Weed Biocontrol and other Control Methods Chemical ControlPicloram (Tordon)2,4-DGlyphosateDicambaCultural Controlgrazing(sheep, goats)hand-pulling, tillingburningIPMBiological Control- insectspathogens
22 What is Biological Control of Weeds? The use of one organism to control another.Classical Biological Control is the introduction of control agents- usually insects- into a region that is not part of their natural range, to suppress permanently the populations of selected target weeds usually also introduced into that regionSUPPRESS not GET RID OF!Mostly geared towards containment list
23 How Biological Control Works Biocontrol agents may control weeds by destroying seeds, root, or stems; by weakening or stressing the weed; and/or by limiting the weeds ability to reproduce.Bioagent feeding may also help secondary pathogens infect weeds through damage scars.Once established and feeding in your weed infestations, biological control agents will continue to attack your weeds, month after month, year after year.
25 Biological Control Agent Outbreaks May Control Weed Infestations Beverly Bridge, ABAphthonanigriscutisLeafy Spurge
26 Aphthona flea beetles for leafy spurge Biocontrol agents behave like insect pest speciesMass outbreaks
27 Biological Control Basics: Uncertainty over ultimate scale of impactLong-term cost effectiveIrreversibleSelf dispersing (even into difficult terrain)Uncertain ‘non-target’ effects in ecosystemsGradual in effect, generally environmentally benignProtracted time until impact likelyContinuous actionInitial high costsTarget specificityDisadvantagesAdvantages
28 Things to Know: Efficiency of agents cannot be be be be be guaranteed. Will not work every time in every situation.Will not “eradicate” the weed.May not provide the desired level of control.Some times it might take awhile (years) before see biological control impact.