Submitted to: Poisonous Plant Global Research and Solutions
Publication Type: Book / Chapter
Publication Acceptance Date: 5/31/2006
Publication Date: 6/20/2007
Citation: Gunn, D., Panter, K.E. 2007. Poisonous range plants on the fort hall reservation in southeastern idaho. Poisonous Plant Global Research and Solutions, Chpt. 72, pp. 423 - 431. Interpretive Summary: The Fort Hall Indian Reservation in southeastern Idaho consists of approximately 302,483 acres of rangeland mainly utilized for cattle grazing by both tribal and non-tribal permittees. This expansive rangeland is divided into 14 range units. Each unit has unique characteristics in regard to vegetative species, soil characteristics, topography, water developments and use. Permittee lease payments provide a source of income for the Shoshone tribe and individual tribal members. Many tribal members are also cattle producers and derive their main source of income by running cattle on reservation rangelands. One of the issues of concern is poisonous range plants within these range units. Permittees incur economic losses every year in the form of death loss, animal health problems and calf deformities due to ingestion of poisonous plants. The development of projects to identify poisonous range plants on each of the 14 grazing units of the reservation will benefit the tribe and tribal members by developing improved management strategies to decrease death loss, increase awareness of the problem and improve the economic value of these rangelands.
Technical Abstract: Ranchers utilizing grazing permits on the Fort Hall Indian Reservation incur economic losses every year from poisonous range plants. Several suspect range plants are found on the reservation and include, but are not limited to the following species; bur buttercup (Ranunculus testiculatus), milkvetchs including Astragalus beckwithii, A. mollissimus, A. stenophyllus. A. utahensis and A. vexilliflexux, houndstongue (Cynoglossum officinale), leafy spurge (Euphorbia escula), death camas (including Zigadenus paniculatus, S. venenosus and Z. elegans), broom snakeweed (Gutierrezia sarothrae), Kochia (Kochia scoparia), poison-hemlock (Conium maculatum), water hemlock (Cicuta douglasil), lupine (Lupinus spp.), Russian knapweed (Centaurea repens), low larkspur (Delphinium nuttallianum) and plains larkspur, lupine and Russian knapweed. Death losses of approximately 1-3% are incurred each year due to larkspur poisoning. Lupine is well known for the calf defects it can cause if ingested during the first trimester of pregnancy. Some reservation permittees experience lupine-induced “crooked calf disease” including cleft palates every year. Russian knapweed has caused chewing disease in horses on the Reservation and is considered a noxious weed also. Some of these poisonous plants degrade range condition and decrease range land value. For these reasons, we are developing a project to identify poisonous range plants on each of the 14 grazing units of the reservation. These range plants will be collected during the growing season, identified and chemically analyzed to characterize toxin profiles at different phenological stages to determine relative grazing risk. This information will be disseminated to the Tribe, tribal members and permittees via range tours, individual ranch visits, workshops, newsletter, etc., to help reduce livestock losses. Continued development and implementation of the Fort Hall Poisonous Range Plant Project will benefit the tribe and tribal members by developing improved management strategies to decrease death loss, increase awareness of the problem and improve the economic value of these rangelands.