In Wyoming, landowners are required by state statute (W.S. 11-5-101 - 120) to prevent the spread of invasive plants on their property. There are five primary management strategies that can be combined to create a tailored management plan that is specific to each unique location based on the species present while incorporating the priorities of each individual landowner or manager.
Sometimes called Integrated Weed Management or Integrated Pest/Plant Management (IPM), IPM is the coordination of multiple management strategies to reduce or eradicate invasive plants. Benefits of utilizing IPM include:
- Reduce reliance on any one management technique
- Balances economic and environmental impacts
- Ensures longevity of control methods
For additional information on how TCWP utilizes IPM visit TCWP management page
Management Strategies
Prevention
Preventing the introduction, spread, or establishment of a species. By preventing the introduction of seeds and other reproductive parts, you can reduce the overall time, effort, and inputs needed for management.
A single perennial pepperweed plant can produce more than 3000 seeds?
How can you prevent the spread and introduction of invasive plants?
- While You Recreate: protecting our wild and scenic areas is the responsibility of tourists and residents. No matter what you do to recreate in Teton County, clean your gear between sites, trailheads, and lakes. PlayCleanGo - Stop invasive species in your tracks.
- When Developing Your Property: development is one of the primary means of introducing or spreading invasive plants. Disturbing soil provides invasive plants with an area free of competition to proliferate, and contaminated equipment and planting materials can introduce invasive plants from miles away. Teton County Land Development Regulations require an invasive species management plan with all grading permits.
- When Purchasing Products: Weed Free Products including hay, gravel, and mulch are certified to be free of seeds and other reproductive parts. Certified Weed Free Forage is required on federal lands in Teton County. Reputable sources of seeds and landscaping materials are bound by state and federal law to carry products that are free of state and federally listed weed species.
- After Finding a New Invasive Plant: if a single new plant is found, quickly removing and eradicating it will prevent establishment and spread. TCWP conducts an Early Detection and Rapid Response Program for our highest priority species free of charge.
- Spreading the Word - preventing the spread of invasive plants is all of our responsibility. You can help spread the word in your neighborhood by joining our Neighborhood Advocate program.
Cultural
Utilizing lawn and land management techniques to prevent the introduction of invasive plants. A healthy landscape has fewer places for invasive plants to germinate and creates more robust desirable plants that are able to outcompete any invasive plants that are introduced.
Standing water from flood irrigation is the primary source of nuisance mosquito habitat in Teton County.
How can you create a healthy landscape?
- Mowing - find the appropriate mowing height for your turf to maximize density and health. In grazed areas, rotate livestock to prevent overgrazing.
- Fertilization - use fertilizers when necessary and in proper amounts. Have soil tested to ensure that landscape needs are being met without using unnecessary products. Overuse of fertilizers, especially nitrogen, can burn plants creating dead spots that are vulnerable to invasive plants. Fertilizers are also highly mobile and excess amounts can be washed away into our streams and rivers where they are toxic to aquatic species and cause algal blooms.
- Irrigation - optimize water use to avoid both over and under irrigating. Allow grasses and landscape plants to establish extensive root systems with deep, infrequent watering. Overwatering and allowing irrigation water to pool weakens the root system and makes desired plants less competitive.
- Mulching - use mulch or landscaping fabric to prevent invasive plants from establishing. Spaces in between and around landscaped plants can be colonized by invasive plants. Mulch and landscaping fabric keep these areas covered until desired plants are established.
- Plant Selection - utilize plant species that are adapted to the environment in Teton County. Planting native species or cultivars bred for the Rocky Mountain region will reduce the overall inputs needed to maintain a healthy landscape. Establish desired plantings and complete revegetation as soon as land disturbance or construction is complete to prevent establishment of invasive plants.
Additional guidance and regulations:
- Teton Conservation District - Native Plants information
- Trout Friendly Lawns - Trout Friendly Lawns is a voluntary program that aims to curb nutrient pollution in our waterways from overuse and over watering while improving landscapes and natural habitats.
- Land Development Regulations - Teton County and the Town of Jackson have regulations for plant selection and irrigation requirements for new landscapes.
Mechanical
Physically removing or managing invasive plants with tools or other implements. Some species can be completely removed and eradicated in an area through mechanical management. For other species, mechanical management can make plants less competitive, reduce spreading, and reduce the amount of herbicide needed.
What are the different types of mechanical management?
- Hand pulling - physically removing plants by hand. Hand pulling works best when the soil is moist and on plants with taproots or fibrous roots. Small infestations of rhizomatous plants may be managed with repeated pullings. Remove as much of the root material as possible.
**Wear gloves when handling plants - some species are toxic and some are known allergens** - Tillage/Chopping/Digging - using a tool, such as a shovel, trowel, cultivator, or dandelion fork, to remove plants and their roots. Plants with taproots can be easily managed by severing the root below the crown, or growing point, about 3 inches under ground. Plants with fibrous roots can also be managed using a form of tillage, but as much of the root system should be removed as possible which requires removing more soil from around the plant. Rhizomatous plants can sometimes be managed with deep, repeated tillage.
- Mowing/Cutting/Grazing - removing above ground plant material. Mowing does not eradicate plants. It can prevent seed production which prevents spreading, and it can help deplete root nutrient stores which reduces the competitiveness of invasive plants. Mowing and cutting should occur before plants go to seed and may need to be repeated throughout the growing season depending on the target species. Controlled or rotational grazing can be used to the same effect.
**Some species are toxic to livestock** - Smothering/Solarization - using mulch, landscaping fabric, or landscaping plastic to inhibit plant growth and kill vegetation. Mulching and landscaping fabric can prevent establishment of invasive plants. Consistent and long term use of heavy landscaping plastic can kill vegetation. When combined with solar radiation, this process is called solarization which can sterilize soil killing even the hardiest of seeds.
- Burning - using controlled burns or direct heat/flame to kill invasive plants. Controlled burning can be used to remove above ground material much like mowing. Direct flaming uses a torch to selectively kill small plants. Similarly, boiling water/steam systems direct scalding water or steam to kill small plants.
Important Considerations for Mechanical Management:
- Some species thrive under cultivation. Disturbing root systems of these species can create flushes of growth.
- Reproductive vegetative parts, like rhizomes, stolons, and tubers, can be moved on equipment and in soil. Ensure that equipment is cleaned between sites, and do not move soil from contaminated areas off site.
- Extensive mechanical management on slopes can cause erosion.
- Disturbing soil and killing vegetation through smothering prime areas for infestation by other invasive plants. Revegetation is necessary if large areas are disturbed.
- Mowing or grazing when plants are at seed can spread them off site.
- Always check weather conditions and burning restrictions before using burning as a management tool.
- Some species, like cheatgrass, thrive in fire. They cause fires to burn hotter and faster, killing desirable vegetation. Do not use burning as a management tool for annual grasses.
Seeds from invasive plants can remain in the digestive tract of goats for 72 hours and cattle for up to 1 week.
Biological
Employing living agents to suppress invasive plants. Typically insects or pathogens, these agents are used to suppress, not eradicate, invasive plants by making them less competitive than desirable or native species. Modern biological agents are rigorously tested to ensure they will not pose a threat to native plants, animals, or humans. More detailed information on biological control and agents employed in Teton County is available on our Biological Control page.
Chemical
Using herbicides to manage invasive plants. Herbicides are any chemical substance used to kill or suppress plant growth and include both synthetic and organic herbicides. Herbicides act on plants in many different ways, and not all plants are susceptible to every herbicide.
What are the different types of herbicides? There are several ways to categorize herbicides. These are a few:
Organic and Synthetic
Organic herbicides are derived from naturally occurring sources. Synthetic herbicides are manufactured through a chemical process or through a process that chemically changes a naturally occurring substance.
Organic does not equal safe. Some organic herbicides, like horticultural vinegar, are corrosive, and others may contain ingredients, like clove oil, that are toxic to pets. Always read the label before using any herbicide, and use appropriate protective equipment.
Selective and Non-Selective
Selective herbicides suppress or kill specific groups of plants, like lawn herbicides that kill lawn weeds but not turfgrass. Non-selective herbicides, like glyphosate, kill a wide variety of plants. It is important to consider management priorities when deciding between a selective and non-selective herbicide.
Systemic and Contact
Contact herbicides, including organic and some synthetic herbicides, work by killing or burning the plant material they touch. These can be effective at quickly knowing down plants. They require complete coverage of the plants, and multiple applications may be necessary to fully kill plants. Systemic herbicides are absorbed and move throughout plants. The effect may not be apparent for up to two weeks, but they can effectively kill plants with extensive root systems.
Modes of Action
The biological mechanism by which a herbicide kills or suppresses a plant is called the mode of action. Currently there are 26 known modes of action. Some of these include the following:
- Auxin mimic
- Inhibition of acetolactate synthase (ALS)
- Inhibition of cellulose synthesis
- Inhibition of protoporphyrinogen oxidase (PPO)
- Inhibition of enolpyruvyl shikimate phosphate synthase (ESPS)
- Photosystem I electron diversion
Some plants have become resistant to certain herbicides or modes of action. This predominantly occurs in agricultural settings, but it is possible for herbicide resistance to develop in non-crop settings. Herbicide resistance occurs when a single herbicide or mode of action is used repeatedly on a population of plants. It is important to use Integrated Plant/Pest Management and herbicide modes of action to prevent creating resistance.
Managing Invasive Plants on Your Property
After you have determined what invasive plants are on your property, you can create a management plan that will best address each species.
Use the biology of invasive plants against them
Have mostly biennials with taproots? Hand Pulling and digging are great options. An area is covered with rhizomatous plants like Canada thistle? Mow or weed whack frequently to deplete the nutrient stores in roots, and follow with a systemic herbicide treatment after first frost when the plants will pull the most herbicide down to their roots.
Consider the landscape
Are the plants in an area that’s difficult to get to? A systemic herbicide requires fewer applications. Is your lawn covered in oxeye daisy mats? A lawn herbicide rather than a range and pasture herbicide must be used. Is your gravel driveway teaming with musk thistle rosettes? An organic herbicide may be a great solution.
Be realistic about your time, physical, and financial constraints
Do you work full time or spend a lot of time out of the valley? Hiring a private contractor can ensure that management is timely and can complement your own efforts. Do you have mobility constraints? There’s more than one reason our seasonal crews are made up of mostly college aged individuals. Carrying a backpack sprayer and digging plants up all day is hard work. Hiring a private contractor or working with a neighbor can help alleviate limitations. Are you on a tight budget? Doing the work yourself is a great option! TCWP has several cost-share programs available to help alleviate the cost of managing invasive plants on private property.
Programs for Landowners
- Request a Free Consultation
- Cost-Share Program Enrollment
- Order Herbicide
- Private Contractor List