Purple loosestrife control eradication - Ask Extension
How does my client eradicate Purple loosestrife? Chemicals, burning?
Knowledgebase
Purple loosestrife control eradication #880372
Asked August 06, 2024, 10:16 AM EDT
How does my client eradicate Purple loosestrife? Chemicals, burning?
Montmorency County Michigan
Expert Response
Mechanical control.
Small, young patches of purple loosestrife may be pulled or dug from the ground, the more underground material that can be removed, the lower the chances are for reemergence.
Chemical control.
For larger areas, like you have here, Rodeo (active ingredient: glyphosate) is the only effective herbicide labeled for aquatic use.
If there is visible water located near the site at the time of application or it is along the shoreline of the Great Lakes or Lake St. Claire a permit is required prior to making an herbicide application; contact the MI Department of Environment, Great Lakes and Energy (EGLE) Aquatic Nuisance Control Program Staff at<personal data hidden> for more information. Also, a list of approved aquatic herbicides needs to be consulted on the MI EGLE website (https://www.michigan.gov/documents/deq/wrd-anc-approvedherbicides_445623_7.pdf). Rodeo and other glyphosate products are on this list.
Biological control.
Biological control of purple loosestrife has been successful in Michigan. A root boring weevil and two leaf eating beetles have been released in Michigan over the years. Your local conservation district may know if any biological controls have been released in your area in the past (https://www.alpenamontcd.org/).
Drs. Doug Landis and Mariana Szucs from MSU have communicated to me in the past that collecting existing beetles from areas in Michigan where they have been deployed previously and moving them to your location might be more successful, or easier, and less costly than purchasing them. Dr. Landis stated that the best time to collect them for redistribution is mid-May. There are instructions for this here: https://wiki.bugwood.org/Archive:Loosestrife/Obtaining_Biocontrol_Agents
The process of utilizing biological controls is complicated and requires patience. Once biocontrols are deployed you can expect and ebb and flow type process versus quick eradication.
Other resources.
In Michigan there are several groups working to eradicate invasive plant species. Each group covers a cluster of counties and is funded by varying sources, some volunteer efforts, and sometimes property owners themselves. Groups have varying priority species and their abilities to help vary. If they are not able to help with a particular species of interest they still may be able to point you toward local, reputable companies that can help. You can find your CISMA at this site: https://www.michigan.gov/invasives/take-action/local-resources Usually there is a coordinators email and phone number listed and sometimes there is also a web address (or you can do an internet search for the group’s name).
Please let me know if you have more questions.
Small, young patches of purple loosestrife may be pulled or dug from the ground, the more underground material that can be removed, the lower the chances are for reemergence.
Chemical control.
For larger areas, like you have here, Rodeo (active ingredient: glyphosate) is the only effective herbicide labeled for aquatic use.
If there is visible water located near the site at the time of application or it is along the shoreline of the Great Lakes or Lake St. Claire a permit is required prior to making an herbicide application; contact the MI Department of Environment, Great Lakes and Energy (EGLE) Aquatic Nuisance Control Program Staff at<personal data hidden> for more information. Also, a list of approved aquatic herbicides needs to be consulted on the MI EGLE website (https://www.michigan.gov/documents/deq/wrd-anc-approvedherbicides_445623_7.pdf). Rodeo and other glyphosate products are on this list.
Biological control.
Biological control of purple loosestrife has been successful in Michigan. A root boring weevil and two leaf eating beetles have been released in Michigan over the years. Your local conservation district may know if any biological controls have been released in your area in the past (https://www.alpenamontcd.org/).
Drs. Doug Landis and Mariana Szucs from MSU have communicated to me in the past that collecting existing beetles from areas in Michigan where they have been deployed previously and moving them to your location might be more successful, or easier, and less costly than purchasing them. Dr. Landis stated that the best time to collect them for redistribution is mid-May. There are instructions for this here: https://wiki.bugwood.org/Archive:Loosestrife/Obtaining_Biocontrol_Agents
The process of utilizing biological controls is complicated and requires patience. Once biocontrols are deployed you can expect and ebb and flow type process versus quick eradication.
Other resources.
In Michigan there are several groups working to eradicate invasive plant species. Each group covers a cluster of counties and is funded by varying sources, some volunteer efforts, and sometimes property owners themselves. Groups have varying priority species and their abilities to help vary. If they are not able to help with a particular species of interest they still may be able to point you toward local, reputable companies that can help. You can find your CISMA at this site: https://www.michigan.gov/invasives/take-action/local-resources Usually there is a coordinators email and phone number listed and sometimes there is also a web address (or you can do an internet search for the group’s name).
Please let me know if you have more questions.
