Invasive weeds threaten the ecological integrity of aquatic environments in Montana.  Eurasian watermilfoil, curly-leaf pondweed and flowering rush have become established in the state, and there is a high risk of invasion by other non-native aquatic plants.

These plants are highly competitive and affect fisheries, native plants, waterworks, power generation and irrigation.  Increased aquatic plant biomass also impacts water quality and recreational resources.

Invasive aquatic plants are transported by hitching a ride on animals, watercraft and recreational vehicles, as well as scuba, fishing and hunting equipment.

How can you help?

Boating - Before launching & before leaving:

• Inspect boat, trailer, and equipment.
• Remove aquatic plants, animals, and mud.
• Drain water from boat, motor, bilge, live wells, and bait containers.
• Spray/rinse boats and recreational equipment with high pressure, and/or water above 140 degrees, or let recreational equipment dry for at least five days.

Fishing

• Clean waders and boots.
• Drain water from bait containers.

Hunting & Other Outdoor Activity

• Inspect equipment, decoy lines, anchors, waders and pets.
• Remove weeds/seeds by washing equipment and brushing or cleaning animals.

List of Montana aquatic noxious weeds:

• Eurasian Watermilfoil (Myriophyllum spicatum)
• Purple Loosestrife (Lythrum salicaria)
• Saltcedar (Tamarix ramosissima)
• Yellowflag Iris (Iris pseudoacorus)
• Flowering Rush (Butomus umbellatus)

Other aquatic plants of concern in Montana:

• Hydrilla (Hydrilla verticillata)