Missouri Landowner Duty To Control Noxious Weeds

RSMo §263.190 opens by defining the term: subsection 1 says a 'noxious weed' means any weed the director of the Department of Agriculture designates as noxious by rule, and the department must maintain a public list and adopt any additions through the formal rulemaking process in chapter 536. Subsection 2 then imposes the actual duty on 'every owner of lands in this state,' a list that expressly reaches persons, corporations, partnerships, the state highways and transportation commission, state departments and agencies, county commissions, township and school boards, drainage boards, incorporated cities, and railroad companies.

The standard isn't a fixed height or a calendar date; it's a performance test: control the weeds 'so often in each and every year as shall be sufficient to prevent such noxious weeds from going to seed.' An owner who knowingly lets noxious weeds go to seed forfeits $100 per offense to the county commission, recoverable through a civil action the prosecuting attorney files in the county commission's name before an associate circuit judge; every dollar collected goes into the county's control fund, not the state's general revenue.

Subsection 3 requires due process before any lawsuit: the prosecuting attorney must notify the landowner by certified mail, return receipt requested, using the address list the tax-list officer supplies, and give the owner 15 days from the acknowledgment or refusal date to start controlling the plants. Failing to act inside that window is 'prima facie evidence' the owner knowingly violated the law, and every additional 15-day stretch the weeds stay uncontrolled counts as a fresh, separately punishable offense, so a season of neglect can multiply well past the first $100.

Subsection 4 adds a flat rule with no notice requirement at all: 'all sales of noxious weed species are prohibited.' The same chapter goes further for one specific plant: RSMo §263.250 separately declares cannabis sativa a noxious weed that every owner or occupier must destroy, and lets a sheriff or county-designated agent enter the land and destroy it after 15 days' certified-mail notice or a search warrant, with the county commission covering the cost.

Knowingly letting noxious weeds go to seed forfeits $100 per offense to the county commission under §263.190.2, recovered by the prosecuting attorney through civil action, with proceeds earmarked for the county control fund. Because every 15-day period of continued noncompliance after the notice period is a separate offense under §263.190.3, unresolved violations can stack well beyond the first $100. Selling noxious weed species outright is barred by §263.190.4, with no notice-and-cure period attached.