ARS | Publication request: Immigrant forage kochia: A closer look at this rangeland plant

Submitted to: The Progressive Rancher
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: October 25, 2011
Publication Date: December 15, 2011
Citation: Clements, D.D., Waldron, B.L., Mccuin, G. 2011. Immigrant forage kochia: A closer look at this rangeland plant. The Progressive Rancher. 5(8):16-17.

Interpretive Summary: ‘Immigrant’ forage kochia (Bassia prostrata, formerly Kochia prostrata) is a perennial semi-evergreen half shrub that averages 1 to 3 feet in height (Figure 1) and has been widely used in revegetation efforts throughout the western United States. Forage kochia is native to the arid and semi-arid regions of Central Eurasia and belongs to the Chenopod family which includes other valuable arid rangeland species such as winterfat (white sage), saltbushes and green molley. It should not be confused with annual kochia (Kochia scoparia), which invades roadsides, croplands and disturbed sites throughout the west. Forage kochia is well adapted to a wide range of soil textures including sandy, clay, gravelly, stony, loam and silt. Forage kochia also grows in habitats that receive 5 to 27 inches of annual precipitations, and survives the extreme temperatures (-25 to 104ºF) found in arid deserts. In the 1960’s, Wesley Keller, former Chief of the Forage and Arid Pasture Unit, USDA, Agricultural Research Service (ARS) and pioneer rangeland scientist Perry Plummer brought to the U.S. numerous parental accessions (plant material collected and assigned a number to maintain its identity during evaluation) of forage kochia from central Eurasia republics of the USSR, as a possible plant that could be used to suppress the exotic and toxic weed Halogeton (Halogeton glomeratus). These researchers determined that forage kochia was excellent winter forage, especially for livestock and wintering mule deer herds, was competitive with cheatgrass, slowed the spread of wildfires, and was widely adapted to the semi-arid cold deserts of the western U.S. The first forage kochia variety was released in 1984 and given the name ‘Immigrant’. Its intended rangeland use included, soil stability, fire prevention, plant community diversity, plant cover, and forage for domestic livestock and wildlife. For some time now there has been controversy in using introduced species such as ‘Immigrant’ forage kochia in rangeland revegetation efforts. Advocates claim that ‘Immigrant’ forage kochia provides critical nutritional values as well as reducing the chance, rate and spread of wildfires on rangelands that would otherwise be completely dominated by the highly flammable and invasive annual grass, cheatgrass. Opponents argue that ‘Immigrant’ forage kochia decreases genetic integrity of the range, that it is invasive, and that it can cause harm or death to livestock. There are many examples of plants that were unintentionally or even intentionally introduced to the U.S. and later became invasive weeds that survive, reproduce and spread causing environmental or economic harm. Cheatgrass and salt cedar would be two good cases in points. Research conducted over the last 25+ years by the USDA-ARS Logan, Utah and Reno, Nevada research facilities has reported that ‘Immigrant’ forage kochia kochia will “naturally recruit, like most species, mainly into disturbed soils or in areas lacking competition from perennial vegetation, both within and outside the seeded area.” They went on to add that at most sites they observed the spread of ‘Immigrant’ forage kochia was less than 12 feet and that there was no evidence that there was more spread at the older plantings, which would be expected of a highly invasive species. Overall, the ARS researchers have concluded that ‘Immigrant’ forage kochia is not a species that invades another plant community and displaces established native species. In 2004, reports surfaced that ‘Immigrant’ forage kochia was suspected of causing nitrate poisoning in livestock in Nevada and Wyoming. Forage kochia’s weedy cousin, K. scoparia is a known nitrate accumulator so Waldron led a team of investigators to determine if forage kochia was safe for livestock consumption. The team sampled forage kochia at multiple locations in Nevada, Wyoming, Utah, and Oregon during

Technical Abstract: ‘Immigrant’ forage kochia (Bassia prostrata, formerly Kochia prostrata) is a perennial semi-evergreen half shrub that averages 1 to 3 feet in height and has been widely used in revegetation efforts throughout the western United States. Forage kochia is native to the arid and semi-arid regions of Central Eurasia and belongs to the Chenopod family which includes other valuable arid rangeland species such as winterfat (white sage), saltbushes and green molley. It should not be confused with annual kochia (Kochia scoparia), which invades roadsides, croplands and disturbed sites throughout the west. In the 1960’s, Wesley Keller, former Chief of the Forage and Arid Pasture Unit, USDA, Agricultural Research Service (ARS) and pioneer rangeland scientist Perry Plummer brought to the U.S. numerous parental accessions (plant material collected and assigned a number to maintain its identity during evaluation) of forage kochia from central Eurasia republics of the USSR, as a possible plant that could be used to suppress the exotic and toxic weed Halogeton (Halogeton glomeratus). These researchers determined that forage kochia was excellent winter forage, especially for livestock and wintering mule deer herds, was competitive with cheatgrass, slowed the spread of wildfires, and was widely adapted to the semi-arid cold deserts of the western U.S. The first forage kochia variety was released in 1984 and given the name ‘Immigrant’. For some time now there has been controversy in using introduced species such as ‘Immigrant’ forage kochia in rangeland revegetation efforts. Opponents argue that ‘Immigrant’ forage kochia decreases genetic integrity of the range, that it is invasive, and that it can cause harm or death to livestock. Overall, the ARS researchers have concluded that ‘Immigrant’ forage kochia is not a species that invades another plant community and displaces established native species. In 2004, reports surfaced that ‘Immigrant’ forage kochia was suspected of causing nitrate poisoning in livestock in Nevada and Wyoming. Forage kochia’s weedy cousin, K. scoparia is a known nitrate accumulator so Blair Waldron led a team of investigators to determine if forage kochia was safe for livestock consumption. Data showed that nitrate levels in ‘Immigrant’ forage kochia averaged 0.04 % (dry wt. basis) with the highest observed level of 0.22 % in June in Wyoming. These values are well below the 0.5 to 1.0 % nitrate levels that are generally considered slightly dangerous to acutely toxic in livestock. These results are in full agreement with early reports and long-term grazing experience that ‘Immigrant’ forage kochia is safe and does not cause nitrate toxicity. This paper is an attempt to address these concerns and to hear back from agriculture producers, wildlife and other resource managers, as well as the general public in an effort to move forward on future use of this species on western rangelands.