disposal of garlic mustard

Asked June 11, 2020, 3:18 PM EDT

We have a 10 acre property in Livingston County that is partly wooded and partly grass/former farm pasture. We have an infestation of garlic mustard. In some areas of the property it is still relatively spotty, in others there is a lot of 1st year ground growth, and in some areas it is widespread and risking monoculture. We have been working to pull and use herbicides to push it back. At this point our problem is disposal of plants that we have pulled out. We cannot include in the trash pick up with our disposal company because they accept only leaves and grass in paper bags. We have a great number of 3 mil plastic bags holding the plants right now. Is there a place in Michigan that we could take these bags for disposal? Is there another safe way to dispose without risking ongoing contamination? Also, we have read about more specific herbicides (using Round Up now) - are these available for purchase in retail settings or on line? We are feeling pretty hopeless about being able to eradicate the infestation. Thanks for your help.

Livingston County Michigan

1 Response

Your trash disposal company should take them in plastic bags headed for the landfill. Michigan law allows for this when it is an invasive species like garlic mustard. Here's a document with more information.
https://www.michigan.gov/documents/invasives/Invasive_Plant_Disposal_Guide_accessible_word_626157_7.pdf
Maybe you could give them a call and explain the situation and ask. Otherwise if there is a landfill where you can take them directly that would work, though it's not very convenient.

There are herbicides that can be effective for controlling garlic mustard. Rebecca Finneran recently wrote an article that may be helpful. (https://www.canr.msu.edu/news/garlic_mustard_may_be_michigans_worst_woodland_weed) . Roundup Weed and Grass Killer (active ingredient glyphosate, and there are many other products with that same active ingredient) can be used for garlic mustard control.

When using products containing glyphosate there are a few important points to consider. First, as with any pesticide, remember to read and follow all labeled instructions. Second, glyphosate is a broad-spectrum herbicide, meaning it will injure or kill other plants contacted during application, so care is needed to avoid green plant material, exposed roots, and injured bark of desired plants. Third, glyphosate is relatively safe in the environment when used as labeled. It adsorbs strongly to soil in most cases (i.e. clay and organic matter), allowing even sensitive crops to be planted shortly after application; meaning no carry over issues are expected. Fourth, glyphosate alone can take up to 14 days to show full activity under ideal growing conditions. Retreatment of the area may be needed depending on the degree of infestation. Glyphosate can be applied anytime the plants are actively growing (temperatures consistently above 50F). Finally, be sure that the product you choose has only the active ingredient glyphosate or glyphosate + pelargonic acid. Products with additional active ingredients may have other unwanted effects and may delay the planting of other plants in the coming season(s).

The article also mentions a product that can deter germinating seedlings (trifluralin), but that may not be desired if you have a lot of other wild plants germinating from seed.

Please let me know if you have any more questions either here or via direct email (hiller12@msu.edu).