The Enemy: Wild angelica (Angelica sylvestris)
Strategy: This short-lived perennial invades ditch banks, moist fields, meadows and pastures. It looks identical to water hemlock, the difference being the leaf. Angelica has serrated leaves like water hemlock, but the veins in water hemlock terminate in the valleys of the serrations, where the veins terminate at the peaks of the serrated leaves in angelica. Angelica also is completely edible where hemlock is completely toxic. It has an umbulatory white flower cluster. It grows to 6 feet tall, where Water hemlock usually grows to 4 feet tall.
Attack: As this plant usually grows in and on irrigations ditches, it blocks water from being able to flow down the waterway. When it invades a moist meadow or pasture, its roots allow it to compete against desirable vegetation. It normally is not grazed upon by livestock, so it can become the dominate plant. It produces tens of thousands of seeds per plant, spreading quickly.
Defense: Preventing this plant from invading is one of the best methods of control. Mainly by keeping the meadow or pasture healthy by practicing good land management with water and grazing programs. If one or two plants are found, digging them up can be most effective. Once established, one can treat with herbicides that work well for plants in the carrot family. Early in the year, Dicamba and 2,4-D can be used. When the weeds get taller, products such as Telar XP, Escort XP or Opensight work best. Opensight is labeled for use on the outer side of a canal or ditch but not in the inside of the bank or bottom of the irrigation system.