***IMPORTANT NOTE***

According to Idaho Code 22-2407, Idaho property owners carry the primary burden of controlling noxious weeds on their land.  County Weed Superintendents may only treat noxious weeds on private property if the landowner fails to fully mitigate the situation.  In such instances, the County will treat the noxious weeds and bill the property owner for the weed control efforts. 

Control Poison Hemlock

Poison Hemlock is one of the most common noxious weeds in Ada County. As the name implies, Poison Hemlock contains highly toxic alkaloids. This plant is prevalent in poorly drained soils, particularly along rivers, ditches, and in pastures with high water tables. While horses and cows do not find this plant particularly palatable, it can be accidentally ingested while animals are foraging. This plant is a health hazard to humans and livestock.

Fortunately, Poison Hemlock is easily controlled with herbicides like 2, 4-D. This herbicide controls broadleaved plants, and works very well on Poison Hemlock. Some formulations of 2,4-D are salt based, and can make the plants attractive to livestock for a few days after spraying. All grazing restrictions stated on the herbicide label should be observed, or even extended, based on the individual situation. If Poison Hemlock is growing near water, herbicide options may change, or special steps might need to be taken to protect our waterways. Under no circumstances should herbicides be sprayed, or allowed to drift into any waterway, pond, or stream.

At Ada County Noxious Weed Control, we look forward to discussing your weed control issues with you. Please remember, we have several spray rigs, and can spray most properties for a fee. If you would like, we can provide an estimate of the cost involved beforehand. If you chose to have us treat your property, we ask that you have your property ready to spray when we arrive. This includes unlocking gates, clearing irrigation pipes, removing livestock, and withholding irrigation long enough for us to get a ¾ ton pick-up on it without getting stuck. Weather permitting, we normally arrive on the day we have scheduled to spray your property. In the spring, treatments are often made 2-3 weeks away from when you call us about spraying a property. It is best if you call early to make an appointment. Please tell us if you have any unusual circumstances associated with your spraying needs. Contact us at (208) 577-4646, to discuss and/or schedule treatment.

photos by University of Idaho, Plant, Soils, Entomological Sciences