Prohibited and Restricted Noxious Weed Seeds

Michigan law regulates the sale, advertising, or transport of certain noxious weeds. Noxious weed seeds are generally considered to be serious nuisances or economically detrimental and are divided into two categories. Prohibited noxious weed seed cannot be sold or transported in the state. Restricted noxious weed seeds are only permitted when strict limits on the percentage or number of such seeds found in any lot of seed are observed.

The various Acts and Regulations that pertain to the sale or transport of seed consisting of or containing noxious weeds are summarized below:

  • Act 329 of 1965 - Michigan Seed Law - includes limit on percentage of weed seed
  • Regulation 715 - Seed Law Implementation - lists prohibited and restricted noxious weeds

A complete list of the prohibited and restricted noxious weed seeds covered by Regulation 715 follows:

The number of restricted noxious weed seeds that may be found in any particular lot of seed is limited to 1 seed of any or all of the restricted noxious weed seeds to 2,000 seeds of the seed sold, offered, exposed, or transported for sale, except that for buckhorn and yellow rocket, the limit shall be 1 seed to 1,000 seeds of the seed sold, offered, exposed, or transported for sale. 

If present in a lesser ratio, the seed consisting of or containing the restricted noxious weeds may be sold, provided that the name of the restricted noxious weed(s) must be named on the tag together with the number of the restricted weed seeds per pound, unless they are buckhorn or yellow rocket. If the restricted noxious weeds are either of these, they need not be shown on the tag unless they exceed 90 seeds per pound.