Toxic weed
Western water hemlock is a water-loving flowering plant that is powerfully poisonous to most mammals. Its toxins are highly dangerous and may be absorbed by skin thus avoiding directly touching western water hemlock. Due to its growing habit, western water hemlock may be hard to control.
How to Control it
Considering that these plants are usually found near rivers, streams, irrigation channels and other bodies of water, their management can be quite difficult. The use of chemical pesticides is not advised due to the close proximity of water and the high probability of affecting non-target species. Manual removal is the best option in case of small scale infestation. Keep in mind that western water hemlock is highly toxic and make sure to wear thick gloves, face shield, adequate clothing and waterproof boots when you handle or remove this plant. Dig out entire plants along with their highly toxic roots, put them in bags and dispose of them.