Potential of Forage Kochia and Other Plant Material to Reclaim Gardner Saltbush Ecosystems That Have Been Invaded By Halogeton.

Gardner saltbush ecosystems are increasingly being invaded by halogeton (Halogeton glomeratus), which is extremely competitive and believed to increase soil surface salinity making it difficult to establish other desired plants.  This study evaluated the ability of forage kochia (Kochia prostrata), Russian wildrye (Psathyrostachys juncea), tall wheatgrass (Thinopyrum ponticum), Indian ricegrass (Oryzopis hymenoides) and Gardner saltbush (Atriplex garneri), in monocultures and binary mixtures with Gardner saltbush, to compete and persist in Gardner saltbush ecosystems that are dominated by halogeton.   Halogeton densities were determined at 10 cm interval distances (0-10 cm, 10-20 cm, 20-30 cm, and 30-40 cm) between rows of spaced transplants of these desired species.  The study was located within the Flaming Gorge Nation Recreation Area, Ashley National Forest, Manila, Utah.  This study found that Bozoisky RWR and forage Kochia significantly (P < 0.05) reduced halogeton recruitment at each 10 cm interval in comparison to the control.  Bozoisky RWR reduced Halogeton by 77%, 59%, 49%, and 39% at the 0-10, 10-20, 20-30, and 30-40 cm intervals respectively in comparison to the control.  Forage Kochia had similar competitive ability with a 72%, 42%, 26%, and 21% halogeton reduction at the 0-10, 10-20, 20-30, and 30-40 cm intervals respectively.  Mixtures of Bozoisky RWR and forage Kochia with Gardner saltbush (50:50) also reduced halogeton frequency, albeit by approximately 50% less than monocultures.  Gardner saltbush, tall wheatgrass, and Indian ricegrass were much less competitive in year 1 and did not persist beyond establishment year.  Both Bozoisky RWR and forage Kochia appear to be adapted to these harsh conditions and can compete with halogeton, thereby providing an opportunity for reclamation of areas invaded by halogeton.