Invasive Plant Control Database

Welcome to the Invasive Plant Control Database

This website contains information on how to control many invasive plants common to the Midwestern United States. Information was collected from both scientific literature and expert opinions and summarized by the Midwest Invasive Plant Network (MIPN), in partnership with the Mark Renz lab from the University of Wisconsin-Madison. Methods that are uncommon, do not provide sufficient control, or lack information for determining effectiveness on target species are omitted. For each species, information was reviewed by four individuals, including two identified as experts on control of that species. Information is searchable by several fields to improve the user’s ability to find pertinent information. To view the search feature, you must first select an invasive plant. Additionally, users have the option of entering personal experiences with managing specific species (see “add new case studies” under search results). These case studies will be visible to all users once verified by MIPN staff.

We make no representations or warranties of any kind, express or implied, about the completeness, accuracy, reliability, suitability, or availability with respect to the information or products on the website. Any reliance you place on such information is therefore strictly at your own risk. References to pesticide products on this website are for your convenience and are not an endorsement or guarantee of one product over another.

Step 1: Select Plant

Step 1: Select a species by choosing a common or scientific name from the list, or by typing a name in the search box.

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Step 2: Select Search Parameters

Step 2: Select search parameter(s) of interest. If no parameters are selected all control methods will be displayed. For effectiveness ratings, methods that meet or exceed the criteria selected will be displayed.

Under the Search Results you will find

  • Plant Identification information – information on species identification, including photographs and a current distribution map.
  • Ecological Threats – threats posed to natural ecosystems by this species.
  • Case Studies – Detailed success (and failures) on how to control specific species contributed by experienced personnel.
  • Non-chemical and chemical control methods that fit the selected search criteria. Please note you are responsible for using pesticides in accordance with the label directions and state and federal laws. Herbicide availability and registered uses vary from state to state. Contact your state department of agriculture for information on the correct use and licensing required for any pesticide application.

You may reset the search criteria or the species you have selected at any time by selecting the corresponding links on the right hand side of the page.

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Effectiveness (in season): 


Effectiveness (year after treatment): 
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Search Results

Cirsium arvense (Canada thistle)

Plant Identification information >
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Case Studies
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Non-Chemical controls
New (Type)Description
Type -
Mowing

User Type -
Novice

Effectiveness -
in season
year after treatment
Mow when plant has produced flower buds. Then mow a second time when plant again produces flower buds or when the plant has 7-10 leaves. Late summer/fall mowing will not be as effective as early mowing as plants remain as rosettes. Mowing when plants are drought stressed can increase effectiveness. Mowing will suppress thistle growth, but not control it.
Type -
Prescribed burning

User Type -
Professional

Effectiveness -
in season
year after treatment
Spring burns can kill germinating seedlings and can suppress above ground growth of established plant depending on fire intensity. After the fire, established plants will quickly re-sprout and reinvade areas; this management method is not recommended unless integrated with other techniques. Fire may benefit other species well adapted to this management (e.g. prairie grasses), resulting in improved competition with Canada thistle. A hand-held propane torch can be effective for treating seedlings.
Type -
Removal

User Type -
Novice

Effectiveness -
in season
year after treatment
Pull or cut 3-4 times a year. The first removal should take place when buds are fully developed, then repeat at 4 week intervals as resprouts occur until the plant goes dormant in fall. Pulling or cutting when plant is drought stressed can increase effectiveness. Removal is required for 3-5 years to eradicate perennial plants, but seeds can persist and reinvade areas for up to 20 years. If flowers present, bag material and dispose of in a landfill or burn to avoid potential for seed spread.
Type -
Grazing

User Type -
Novice

Effectiveness -
in season
year after treatment
The optimal time for grazing is similar to hand pulling. Sheep, goats, and cattle may graze Canada thistle before bud stage to reduce flower production, but grazing is more effective when plants are treated with salt or animals are trained to eat these spiny plants. High intensity short duration grazing of plants for 2-3 years in grass-based pastures can reduce stem densities to low levels. Avoid over-grazing a site as it can suppress other vegetation competing with Canada thistle and result in enhancing thistle populations.
Type -
Manipulation of the environment

User Type -
Novice

Effectiveness -
in season
year after treatment
Inter-seeding with competitive grasses can suppress Canada thistle, if grasses successfully establish. This method has been shown to be most effective when paired with other control measures.
Type -
Biocontrol

User Type -
Novice

Effectiveness -
in season
year after treatment
Pseudomonas syringae pv. tagetis (PST) bacterium infects thistles in non-disturbed habitat. Plant mortality rarely occurs as a result of infection and infections do not persist in plants and must be re-infected annually. Infections are increased by mowing or other physical disturbances when moisture is present on foliage. There are a number of other introduced agents that have been used to suppress Canada thistle, but these species are generalist feeders and likely would not be approved for release. Contact your local department of agriculture for information on permits for the release of biological control agents.
Chemical controls
New (Type)IngredientsDirections
Type -
Foliar

User Type -
Professional

Effectiveness -
in season
year after treatment
Active Ingredient (A.I.):
aminocyclopyrachlor + metsulfuron

Common product name:
Streamline
Rate -
(broadcast) 4.75 - 5.5 oz/A (aminocyclopyrachlor: 1.9 - 2.15 oz a.i./A + metsulfuron: 0.6 - 0.7 oz a.i./A)
(spot) 0.2 - 0.4 oz/gal (aminocyclopyrachlor: 0.08 - 0.16 oz a.i./gal + metsulfuron: 0.03 - 0.05 oz a.i./gal)

Timing -
Apply during flower bud to early flowering stage or to rosettes in the fall as long as leaves are green.

Caution -
Do not apply directly to water or to areas where surface water is present. Avoid using Streamline in areas where soils are permeable, particularly where the water table is shallow as groundwater contamination may result. Streamline remains in the soil for months depending on application rate and has the potential to contaminate surface runoff water, especially on poorly draining soils or areas with shallow groundwater. Maintenance of a vegetative buffer strip is recommended between the areas Streamline is applied and surface water features. Overspray or drift to desirable plants should be avoided, as even minute quantities of the spray may cause severe injury to plants. Do not compost treated plants as herbicide can persist through composting process.
Type -
Foliar

User Type -
Novice

Effectiveness -
in season
year after treatment
Active Ingredient (A.I.):
glyphosate

Common product name:
Roundup Pro; many others (Aquatic: Rodeo; AquaNeat)
Rate -
(broadcast) 0.75 - 1.5 lb a.e./A
(spot) For a 3 lb a.e./gal product. 1 - 2% (0.03 - 0.06 lb a.e./gal)

Timing -
Apply during flower bud to early flowering stage or to rosettes in the fall as long as leaves are green.

Remarks -
Wick application is effective when target plants are taller than desirable plants with a 50% solution of product.

Caution -
Use product labeled for aquatic use if potential exists for solution to contact surface waters. Applications can result in bare ground as glyphosate is not selective. Overspray or drift to desirable plants should be avoided, as even minute quantities of the spray may cause severe injury to plants.
Type -
Foliar

User Type -
Professional

Effectiveness -
in season
year after treatment
Active Ingredient (A.I.):
dicamba

Common product name:
Banvel; Clarity
Rate -
(broadcast) 16 - 64 fl oz/A (0.5 - 2 lb a.e./A)
(spot) Equivalent to broadcast rates.

Timing -
Apply during flower bud to early flowering stage or to rosettes in the fall as long as leaves are green.

Remarks -
Most effective when applied to rosettes in the spring or fall.

Caution -
Do not apply directly to water or to areas where surface water is present. Use of this chemical in areas where soils are permeable, particularly where the water table is shallow, may result in groundwater contamination. Overspray or drift to desirable plants should be avoided, as even minute quantities of the spray may cause severe injury to plants. Rates > 16 fl oz/A (0.5 lb a.e./A) may cause stunting and discoloration of sensitive grasses, such as smooth brome.
Type -
Foliar

User Type -
Professional

Effectiveness -
in season
year after treatment
Active Ingredient (A.I.):
clopyralid

Common product name:
Transline
Rate -
(broadcast) 10 - 16 fl oz/A (0.25 - 0.4 lb a.e./A)
(spot) 0.2 - 0.4% (0.005 - 0.01 lb a.e./gal)

Timing -
Apply during flower bud to early flowering stage or to rosettes in the fall as long as leaves are green.

Remarks -
Wick application is effective when target plants are taller than desirable plants with a 2% solution of product.

Caution -
Do not apply directly to water or to areas where surface water is present. Use of this chemical in areas where soils are permeable, particularly where the water table is shallow, may result in groundwater contamination. Remains in soil for up to one year depending on application rate. Overspray or drift to desirable plants should be avoided, as even minute quantities of the spray may cause severe injury to plants. Do not compost treated plants as herbicide can persist through composting process.
Type -
Foliar

User Type -
Professional

Effectiveness -
in season
year after treatment
Active Ingredient (A.I.):
picloram + 2,4-D

Common product name:
Tordon 101
Rate -
(broadcast) 64 - 96 fl oz/A (picloram: 0.25 - 0.4 lb a.e./A + 2,4-D: 1 - 1.5 lb a.e./A)
(spot) 1 - 1.5% (picloram: 0.005 - 0.008 lb a.e./gal + 2,4-D: 0.02 - 0.03 lb a.e./gal)

Timing -
Apply during flower bud to early flowering stage or to rosettes in the fall as long as leaves are green.

Caution -
Do not apply directly to water or to areas where surface water is present. Use of this chemical in areas where soils are permeable, particularly where the water table is shallow, may result in groundwater contamination. Remains in the soil for over one year depending on application rate and has the potential to contaminate surface runoff water during this timeframe. Maintenance of a vegetative buffer strip is recommended between the areas this product is applied and surface water features. Overspray or drift to desirable plants should be avoided as even minute quantities of the spray may cause severe injury to plants. Do not compost treated plants as herbicide can persist through composting process.
Type -
Foliar

User Type -
Professional

Effectiveness -
in season
year after treatment
Active Ingredient (A.I.):
picloram

Common product name:
Tordon K; Trooper 22K
Rate -
(broadcast) 64 - 96 fl oz/A (1 - 1.5 lb a.e./A)
(spot) Equivalent to broadcast rates.

Timing -
Apply during flower-bud to early flowering stage or to rosettes in the fall as long as leaves are green.

Caution -
Do not apply directly to water or to areas where surface water is present. Use of this chemical in areas where soils are permeable, particularly where the water table is shallow, may result in groundwater contamination. Remains in the soil for over one year depending on application rate and has the potential to contaminate surface runoff water during this timeframe. Maintenance of a vegetative buffer strip is recommended between the areas picloram is applied and surface water features. Overspray or drift to desirable plants should be avoided as even minute quantities of the spray may cause severe injury to plants. Do not compost treated plants as herbicide can persist through composting process.
Type -
Foliar

User Type -
Novice

Effectiveness -
in season
year after treatment
Active Ingredient (A.I.):
2,4-D

Common product name:
Many (Aquatic: DMA 4 IVM; 2,4-D Amine 4)
Rate -
(broadcast) 1 - 2 lb a.e./A
(spot) For a 3.8 lb a.e./gal product. 0.5 - 0.8% (0.02 - 0.03 lb a.e./gal)

Timing -
Apply during flower bud to early flowering stage or to rosettes in the fall as long as leaves are green.

Remarks -
This technique will eradicate new, small infestations, but will only suppress well-established populations unless multiple applications are made.

Caution -
Use aquatically labeled product if potential exists for solution to contact surface water. Use of this chemical in areas where soils are permeable, particularly where the water table is shallow, may result in groundwater contamination. Overspray or drift to desirable plants should be avoided, as even minute quantities of the spray may cause severe injury to plants.
Type -
Foliar

User Type -
Professional

Effectiveness -
in season
year after treatment
Active Ingredient (A.I.):
aminopyralid

Common product name:
Milestone
Rate -
(broadcast) 5 - 7 fl oz/A (0.08 - 0.1 lb a.e./A)
(spot) Equivalent to broadcast rates.

Timing -
Apply during flower bud to early flowering stage or to rosettes in the fall as long as leaves are green.

Remarks -
14 fl oz/A can be used as long as less than half of the area is treated. Depending on the volume of solution applied per acre, typical mixtures for spot treatments are 2-8 mL Milestone per gallon of water.

Caution -
Do not apply directly to water or to areas where surface water is present. Remains in soil for up to one year depending on application rate. Overspray or drift to desirable plants should be avoided, as even minute quantities of the spray may cause severe injury to plants. Do not compost treated plants as herbicide can persist through composting process.