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Aminopyralid, a pyridine carboxylic acid herbicide, controls noxious and invasive broadleaf weeds in rangeland, permanent grass pastures, Conservation Reserve Program areas, non-cropland areas including industrial sites, rights-of-way (roadsides, electric utility and communication transmission lines, pipelines, and railroads), non-irrigation ditch banks, natural areas (wildlife management areas, wildlife openings and habitats, recreation areas, campgrounds, trailheads and trails), and grazed areas in and around these sites. Registered products include aminopyralid alone (Milestone®) or mixed with other herbicides, metsulfuron (Opensight®), clopyralid (Sendero®), triclopyr (Capstone®), or 2,4-D (ForeFront® HL). Current labels state, “It is permissible to treat non-irrigation ditch banks, seasonally dry wetlands (such as flood plains, deltas, marshes, swamps, or bogs) and transitional areas between upland and lowland sites.  Milestone can be used to the water's edge.  Do not apply directly to water and take precautions to minimize spray drift onto water. Do not contaminate water intended for irrigation or domestic purposes.  Do not treat inside banks or bottoms of irrigation ditches, either dry or containing water, or other channels that carry water that may be used for irrigation or domestic purposes.” Aminopyralid degradation rate in water in sunlight (0.6 day half-life) is similar to triclopyr, an herbicide registered for aquatic uses (0.5 day half-life).  Research was conducted to support aquatic uses. Residue data from experiments conducted in ponds (Texas and Indiana) and moving water (Oregon and Florida) established tolerances for fish, shellfish and crustaceans and defined aminopyralid dissipation kinetics in water and sediment. Data were submitted to support aquatic uses for aminopyralid-containing products, Milestone, GrazonNext® HL, ForeFront HL, Capstone, and PasturAll® HL. Following approval labels are expected to have no restrictions on recreational or livestock use of water after applications of these products but applications will not be permitted on the inside banks of irrigation ditches."