Michigan noxious weed laws, though rarely enforced, define and regulate prohibited/restricted weeds

These plant species are undesirable from agricultural as well as environmental viewpoints.

Some people define a weed as “a plant out of place.” For farmers, that plant competes for space, light, nutrients and moisture intended for the desired crop. With this in mind, every weed is undesirable and Michigan farmers spend millions of dollars annually on herbicides and seed technology to limit crop losses to weeds. In addition to efforts by agricultural industry to control weed competition, Michigan laws and regulations also attempt to regulate possession and sale of certain weed species. Even though these laws are not actively enforced due to scarcity of state funds, they are useful in providing awareness regarding weeds of special interest.Prohibited plant species identified under Act 451 of 1994, as amended, cannot be sold or grown in the state. The plants, fragments, seeds or a hybrid or genetically engineered variant are specifically prohibited. Better known selections from this list of 12 plants include Japanese knotweed and giant hogweed.Restricted plant species identified under the same act are those that may occur within the state and are generally considered nuisances or economically detrimental and are restricted. These include:

  • Flowering rush
  • Purple loosestrife
  • Eurasian watermilfoil
  • Phragmites (or common reed)
  • Curly leaf pondweed

Noxious weeds are identified in two categories under the Michigan Seed Law (Act 329 of 1965) and Regulations 715 (Under Act 329) Seed Law Implementation.Prohibited noxious weeds – seeds of these species are prohibited as contaminants in seed offered for sale:

  • Ragweed (Common and Giant)
  • Hoary alyssum
  • Mustards
  • Whitetop (aka hoary cress, peppergrass)
  • Plumeless thistle
  • Musk thistle
  • Spotted knapweed
  • Russian knapweed
  • Canada thistle
  • Bull thistle
  • Field bindweed
  • Hedge bindweed
  • Dodder
  • Yellow nutsedge
  • Wild carrot
  • Leafy spurge
  • Morningglory
  • Serrated tussock
  • Poison ivy
  • Horsenettle
  • Perennial sowthistle
  • Johnsongrass
  • Poison sumac
  • Puncturevine

Restricted noxious weed seeds – generally, the limit is one seed per 2,000 of agricultural seed offered for sale:

  • Velvetleaf
  • Wild onion
  • Wild garlic
  • Wild oat
  • Yellow rocket
  • Hairy alyssum
  •  Indian mustard
  • Black mustard
  • Jimsonweed
  • Wild carrot
  • Buckhorn plantain
  • Wild radish
  • Curled dock
  • Giant foxtail
  • Charlock
  • Nightshades (bitter, silver leaf, eastern black, hairy)
  • Fanweed
  • Common Cocklebur

In addition, Michigan also has the “Noxious Weeds Act 359 of 1941” with amendments through 2010. This act is intended to control and eradicate certain noxious weeds. It allows townships, villages and cities to have a lien for expenses incurred in controlling and eradicating these weeds, among other things. In addition to a listing of “noxious weeds” similar to those above, this act allows governing bodies of counties, townships, villages and cities to include other plants regarded as a common nuisance.

For additional information:

Information for this article was derived from the Michigan Department of Agriculture and Rural Development website and the Michigan government website.

Related Events

Related Articles