Aquatic Weed Program

Ditch lined with weeds Agricultural Specialists
308 Permits
Aquatic Vegetation Management Plans
Aquatic Nuisance Species Management Plan
Ditchbank and Aquatic Herbicides
Laws & Rules

The Montana Department of Agriculture oversees the licensing and training of aquatic pesticide applicators in Montana. The application of aquatic herbicides requires a special-use license. Applicators who intend to treat waters with restricted-use aquatic herbicides such as xylene, acrolein, or endathall must attend a special aquatic training session and pass an Aquatic Pest Control Exam for initial certification. Training and testing is offered once a year. The course usually lasts 6 hours with a test immediately following the course.

Aquatic plant growth can be both beneficial and harmful: beneficial in that it promotes the diversification of the aquatic environment to support life forms, yet harmful if aquatic vegetation interferes with other uses of the water body.

The department conducts aquatic herbicide applicator training sessions periodically. These are listed with other applicator training opporunities.

The following is the list of Montana aquatic noxious weeds:

Eurasian Watermilfoil (Myriophyllum spicatum)
Purple Loosestrife (Lythrum salicaria)
Saltcedar (Tamarix ramosissima)
Yellowflag Iris (Iris pseudoacorus)

Other aquatic plant species of concern in Montana are:

Flowering Rush (Butomus umbellatus)
Hydrilla (Hydrilla verticillata)

For additional information, contact an area field office or call:

  Tonda Moon   Leonard Berry
  NWSFF Program Specialist   Pesticide Program Manager
  Phone: 406-444-7819   Phone: 406-444-5400
  Fax: 406-444-7336   Fax: 406-444-7336
  E-mail: tmoon@mt.gov   E-mail: lberry@mt.gov