Will the Use of 2, 5-T To Control Streamside Vegetation Contaminate Public Water Supplies?

Riparian vegetation along two small headwater streams in Pennsylvania and New Jersey was treated with 2,4,5-T. Water samples were collected immediately after treatment and periodically thereafter for three weeks. Odor tests were used to determine the degree of contamination. Results indicated that only slight contamination occurred within the treated sections of streams immediately after treatment and in two instances after the first large storm. No contamination was detected downstream. Vegetation analysis one year after treatment indicated that the ester formulation had completely killed 70 to 81 percent of the stems and that the emulsifiable acid had killed 58 to 78 percent. Results of this study provide additional evidence that phenoxy herbicide, if applied with normal precautions, can be used on municipal watersheds without creating any water contamination.