Maine state law: invasive plants and noxious weeds

Per 7 MRS § 605-A (Sale of invasive plants) and the Maine Department of Agriculture, Conservation and Forestry Invasive Plant Rule (01-001 CMR Chapter 273), it is unlawful to import, export, buy, sell, propagate, transport, or distribute specifically designated invasive terrestrial plant species in Maine, effective January 1, 2018. Designated species include Japanese knotweed (Reynoutria japonica), Japanese barberry (Berberis thunbergii), Norway maple (Acer platanoides), multiflora rose (Rosa multiflora), oriental bittersweet (Celastrus orbiculatus), purple loosestrife, common buckthorn, glossy buckthorn, and others. Property owners are NOT required by state law to remove existing invasive plants on private property but may not propagate or sell them. Beyond the invasive-plant rule, Maine has no statewide noxious-weed management duty comparable to Colorado's CRS 35-5.5-104. Routine tall-grass, common-weed, and unkempt-yard nuisance enforcement is municipal under 30-A MRS § 3001 home-rule authority. Maine DACF maintains the Maine Natural Areas Program for invasive plant identification and removal guidance.

Sale/import/propagation of a designated invasive plant: civil penalty up to $1,500 for the first violation and up to $3,000 for subsequent violations under 7 MRS § 605-A. Municipal weed-nuisance violations vary; typical $50-$500 per day.