Noxious weeds are non-native, invasive plants that threaten public health, the environment, wildlife habitat, native plants, agriculture and recreational areas. Once established in an area, noxious weeds become very difficult and costly to control.
Treat weeds prior to blooming to minimize negative impacts to bees and other pollinators. If treatment must occur during the blooming period, spray early or late in the day when pollinators are least active. It may be necessary to remove flowers from plants before spraying.
Prohibited noxious weeds are annual, biennial, or perennial plants that the commissioner designates as having the potential or are known to be detrimental to human or animal health, the environment, public roads, crops, livestock or other property. There are two regulatory listings for prohibited noxious weeds in Minnesota. Each of the categories on the list includes all cultivars of each species unless otherwise listed as "exempt" or "exemption for" with the exempted cultivar name listed.
The "prohibited-eradicate noxious weeds" category includes noxious weeds that must be eradicated on all lands within the state. Transportation of the propagating parts of prohibited-eradicate noxious weeds is prohibited except as allowed under section 18.82. Prohibited-eradicate noxious weeds may not be sold or propagated in Minnesota. Noxious weeds that are designated as prohibited-eradicate noxious weeds and placed on the prohibited-eradicate noxious weeds list are plants that are not currently known to be present in Minnesota or are not widely established in the state. All prohibited-eradicate noxious weeds must be eradicated.
The "prohibited-control noxious weeds" category includes noxious weeds that must be controlled on all lands within the state. Transportation of the propagating parts of prohibited-control noxious weeds is prohibited except as allowed under section 18.82. Prohibited-control noxious weeds may not be propagated or sold in Minnesota. Noxious weeds that are designated as prohibited-control noxious weeds and placed on the prohibited-control noxious weeds list are plants that are already established throughout the state or regions of the state. At a minimum, these species must be controlled in a way that prevents spread of these species by seed or vegetative means.
The "restricted noxious weeds" category includes noxious weeds and their propagating parts that may not be imported, sold, or transported in the state, except as allowed by permit under section 18.82. Noxious weeds that are designated as restricted and placed on the restricted list may be plants that are widely distributed in Minnesota and for which a requirement of eradication or control would not be feasible on a statewide basis using existing practices.
The "specially regulated plants" category includes noxious weeds that may be native species or nonnative species that have demonstrated economic value, but also have the potential to cause harm in noncontrolled environments. Plants designated as specially regulated have been determined to pose ecological, economical, or human or animal health concerns. Species-specific management plans or rules that define the use and management requirements for these plants must be developed by the commissioner of agriculture for each plant designated as specially regulated. The commissioner must also take measures to minimize the potential for harm caused by these plants.
Federal terrestrial and parasitic listed noxious weeds are prohibited in Minnesota. Federal noxious weeds are selected and enforced by the U.S. Department of Agriculture (USDA) and can be reported to the local Animal Plant Health Inspection Service Office (APHIS) in Minneapolis, MN or to the MDA Noxious and Invasive Weed Program. A list of federal noxious weeds and information about the federal weed program can be viewed at the USDA APHIS web site.
Noxious weeds are undesirable, exotic plant species that are detrimental to natural lands, wildlife habitat and the human uses of these resources. Noxious refers to the species' aggressive behavior, which damages native plant communities or economic crops. Because these species are outside their natural range, they no longer have predation. This allows them to adapt very successfully to our environment and gives them an advantage over native species. Noxious weeds outcompete native plants for food, space, light and nutrients and over time form unproductive monocultures that can not support the diverse wildlife the native species could support.
Noxious weeds enter our ecosystems by hitchhiking on people, animals, water, wind or vehicles. Weeds are also introduced by unsuspecting gardeners, hikers' shoelaces, pet fur, cars and equipment and as stowaways on planes, boats and even in luggage. There are many ways you can help prevent the spread of noxious weeds:
Stewardship and Park Staff are hard at work controlling noxious weeds at every park and attempting to prevent new infestations from taking over. Prevention is key and we must always be on the look out for new invaders. Rapid response is our best defense!
Noxious weed control methods are specific to the species and area being controlled. An integrated management plan utilizing all tools available is the most effective way to successfully control weeds. Control methods include:
Colorado is seeing a dramatic increase in noxious weeds. These invasive non-native plants have been introduced by accident or as ornamental plants. They are devastating thousands of acres of wildlife habitat and natural areas. Left uncontrolled, noxious weeds will form dense monocultures and displace native and desirable plants. Native plant loss affects our ecosystems including wildlife that depends on native vegetation for survival.
Good land stewardship is essential to preventing the spread of noxious weeds. As a landowner it is your responsibility to manage noxious weeds. Knowing what is growing on your property is the first step to making sure noxious weeds are controlled.
Noxious weeds are non-native plants that disrupt native vegetation because they have no natural controls and are able to adapt to varied climate conditions. As a result of the Colorado Noxious Weed Act, noxious weeds have been categorized according to their status: A, B, and C.
Cultural: Methods include: Establishing and managing an adequate population of desirable vegetation to compete with the weeds; utilizing livestock (cattle, goats, sheep) when possible; mulching; burning; and even plastic weed barriers.
The aim of the Noxious Weed Program is to control noxious weeds, the non-native aggressive invaders that replace native vegetation, altering native ecosystems, reduce agricultural productivity, cause wind and water erosion and pose an increased threat to communities from wildfire. We do this by preventing the introduction of new invasive species; eradicating species with isolated or limited populations and containing and managing those invasive species that are well-established and widespread. Grand County Division of Natural Resources identifies and manages State-listed Noxious weeds on all County Rights-of-Way, County properties and we partner with local offices of the USFS and BLM for invasive species control as required by State law. We do not work on private property or private roads.
Noxious weeds are a direct and growing threat to the native environment of Grand County and the west. They threaten the very reasons we live, work, and recreate in Colorado and all Colorado landowners are responsible for controlling noxious weeds on their property.
Noxious weeds become established in soils disturbed by a variety of activities such as construction, motorized vehicles, road maintenance, recreation, improper livestock grazing, and natural disturbances such as a fire. Noxious weed seeds are transported to new sites in numerous ways such as wind, water, tires, people, as well as on or in wild and domestic animals.
Grand County Division of Natural Resources (DNR) operates under a directive from the Colorado Department of Agriculture to control and reduce the spread of noxious weeds in Grand County. This includes all county-owned property, road rights of way, and public lands. Grand County DNR is also focused on providing information and assistance to private landowners to help control the spread of noxious weeds.
The Larimer County weed management program strives to minimize the occurrence of weeds and associated negative impacts on native plant communities, agricultural lands and public corridors in Larimer County.
A weed is often defined as "a plant out of place". This simple definition can refer to many different plants in many settings. A "noxious weed" has a special definition with a legal connotation. The Larimer County Weed District follows the guidelines of the Colorado Noxious Weed Act, which defines "noxious weeds" as plants that are exotic and invasive. Exotic means non-native, or weed species that originated in other parts of the world. Most of the weed species considered noxious in Colorado originated in regions of Europe and Asia with a climate similar to the Rocky Mountains.
For over 50 years, herbicides have been a highly effective method to control weeds and protect crop yields. Herbicides have supported the wide-spread use of no-till and limited cultivation for weed control, improving soil health. However, over reliance on a few key herbicides has caused the development of particularly problematic herbicide-resistant weeds.
Integrated weed management (IWM) combines various methods to reduce or eliminate the effect of weeds on crop production over time, using a combination of practices that are most effective for solving specific weed issues. Techniques include:
No matter which definition is used, weeds are plants whose undesirable qualities outweigh their good points, at least according to humans. Human activities create weed problems since no plant is a weed in nature. Though we may try to manipulate nature for our own good, nature is persistent. Through manipulation, we control certain weeds, while other more serious weeds may thrive due to favorable growing conditions. Weeds are naturally strong competitors, and those weeds that can best compete always tend to dominate. 041b061a72