INTRODUCTION

This publication will be limited to the identification of the ten primary noxious weeds on the primary noxious weed list in Minnesota. This list includes six perennial, three biennial, and one annual weed.

Annual weeds germinate and emerge from seed and complete their life cycle in one growing season. Annual weeds that complete their fife cycle during the period from spring to fall are called summer annuals or just annuals. Annual weeds that complete their life cycle during the period from fall to spring are called winter annuals. There is only one annual weed on the Minnesota Noxious Weed list -- hemp.

Biennial weeds require two growing seasons to complete their life cycle. Biennials form a rosette (clusters of leaves close to the ground) the first year and during the second year they develop a flower stalk, flower, produce seed, and then the plant dies. The three biennial weeds on the Minnesota Noxious Weed list are: bull thistle, musk thistle, and plumeless thistle.

A perennial weed can live for 3 or more years. Perennial weeds may emerge from seed like annuals and biennials, but also emerge from rhizomes, stolons, or other underground storage organs. The six perennial weeds on the Minnesota Noxious Weed list are: field bindweed, purple loosestrife, poison ivy, leafy spurge, perennial sowthistle, Canada thistle.

The Minnesota Noxious Weed Law was enacted to protect the residents of Minnesota from injurious effects of noxious weeds to public health, public roads, environment, crops, livestock, and other property. This law and related statutes are under the general administration of the Commissioner of the Minnesota Department of Agriculture. Day-to-day or routine administration of the state's noxious weed control program is carried out by the Director of the Agronomy Services Division through the Supervisor of the Section of Weed Control. Implementation of the noxious weed law is accomplished through several Regulatory Investigators located throughout the state. One of their primary duties is to see that local governments fulfill their responsibilities in the actual enforcement of the law. The actual enforcement is carried out by local governments through local weed inspectors in townships and cities and County Agricultural Inspectors in every Minnesota county.

A noxious weed, as defined by Minnesota Law, is an annual, biennial, or perennial which is deemed by the Commissioner of Agriculture to be injurious to public health, public roads, environment, crops, livestock, and other property. In Minnesota, there are ten weeds on the primary noxious weeds list. They are:

According to Minnesota law, these primary noxious weeds must be controlled on all private and public land in the state.