Rangeland Ecology & Management, Volume 63, Number 6 (November 2010)
http://hdl.handle.net/10150/635398
2024-03-28T22:09:47ZPotential of Kochia prostrata and Perennial Grasses for Rangeland Restoration in Jordan
http://hdl.handle.net/10150/642836
Potential of Kochia prostrata and Perennial Grasses for Rangeland Restoration in Jordan
Bailey, Derek W.; Al Tabini, Raed; Waldron, Blair L.; Libbin, James D.; Al-Khalidi, Khalid; Alqadi, Ahmad; Al Oun, Mohammad; Jensen, Kevin B.
Six varieties of forage kochia (Kochia prostrata [L.] Schrad.), two Atriplex shrubs native to North America, and four drought-tolerant perennial grass varieties were seeded and evaluated under arid rangeland conditions in Jordan. Varieties were seeded in December 2007 and evaluated in 2008 and 2009 at two sites. Conditions were dry with Qurain receiving 110 mm and 73 mm and Tal Rimah receiving 58 mm and 43 mm of annual precipitation during the winters of 2007/2008 and 2008/2009, respectively. Plants were more abundant and taller (P < 0.001) at Qurain than Tal Rimah in 2008. Forage kochia frequency was 48% and 30% in 2008 at Qurain and Tal Rimah, respectively. However, no seeded plants were observed at Tal Rimah in 2009, suggesting that 58 mm and 43 mm of annual precipitation are insufficient to allow plants to persist over multiple years. At the wetter site, forage kochia abundance in 2009 was similar (P=0.90) to that observed in 2008 and plant height increased (P < 0.001) from 2008 (14.4 cm +/- 1.1 SE) to 2009 (38.4 cm +/- 1.1 SE). Sahro-select and Otavny-select were the most abundant forage kochia varieties (P<0.05), suggesting that these experimental lines could be more adapted to the environmental conditions of Jordan than the commercially available cultivar Immigrant. Frequency of perennial grass varieties declined (P<0.001) at Qurain from 82% +/- 4 SE to 39% +/- 4 SE between 2008 and 2009, respectively. Among grasses, Siberian wheatgrass had better stands than crested wheatgrass, with Russian wildrye being intermediate. Based on this study, forage kochia appears to have great potential for establishing palatable perennial shrubs in arid rangeland conditions in Jordan if annual precipitation is at least 70 mm. Arid-adapted perennial grass varieties might also be useful in rangeland restoration if annual precipitation is over 100 mm.
2010-11-01T00:00:00ZPhenotypic and Genetic Characterization of Western Prairie Clover Collections From the Western United States
http://hdl.handle.net/10150/642835
Phenotypic and Genetic Characterization of Western Prairie Clover Collections From the Western United States
Bhattarai, Kishor; Bushman, B. Shaun; Johnson, Douglas A.; Carman, John G.
Few North American legumes are available for rangeland revegetation in the semiarid western United States. Western prairie clover (Dalea ornata [Douglas ex Hook.] Eaton J. Wright) is a perennial legume with desirable forage characteristics and is distributed in the northern Great Basin, Snake River Basin, and southern Columbia Plateau. Understanding the genetic and ecotypic variability of this species is a prerequisite for developing populations suitable for revegetation purposes. To address this need, we established two common-garden plots of western prairie clover from 22 sites in Idaho, Oregon, and Washington. Significant variation was detected among the collections for all traits measured. Among the measured traits, flowering date was correlated with collection-site temperature and elevation. Population structure estimates from 474 amplified-fragment length polymorphism markers resulted in two distinct, genetically differentiated groups and a third admixed group, and flowering date played a significant role in discriminating those genetic-based groupings of collections. Positive correlations were observed between phenotypic and genetic distance matrices (r = 0.33, P = 0.005), phenotypic and geographic distance matrices (r = 0.35, P = 0.002), and genetic and geographic distance matrices (r = 0.31, P = 0.009). Based on these results, we recommend that two germplasm sources of western prairie clover be developed for use across the collection area, one from the Deschutes River region and the other encompassing Idaho, Washington, and eastern Oregon collection sites.
2010-11-01T00:00:00ZReplication of a 1970s Study on Domestic Sheep Losses to Predators on Utah’s Summer Rangelands
http://hdl.handle.net/10150/642834
Replication of a 1970s Study on Domestic Sheep Losses to Predators on Utah’s Summer Rangelands
Palmer, Brian C.; Conover, Michael R.; Frey, S. Nicole
Lamb losses to predation have historically ranged from 4% to 8% in the western United States but most data are over 30 yr old. We repeated a sheep depredation study conducted from 1972 through 1975 on Cedar Mountain, Utah, to determine how predation rates have changed in the last three decades. Pastures and herd sizes were similar (1 730 lambs) between our study (2006 and 2007) and the prior one. Additionally, 40% of the ranchers in our study also participated in the prior study. During 2006 and 2007, 5.8% of all lambs on Cedar Mountain were lost to all causes compared to 9.5% during the 1970s. Predators were responsible for 87% of all verified lamb losses during our study versus 83% during the 1970s. We estimated that 4.9% of all lambs on Cedar Mountain were killed by predators during our study compared to 7.9% during the 1970s. During our study, coyotes (Canis latrans Say) were responsible for 67% of the depredated lambs, cougars (Felis concolor Linnaeus) for 31%, and black bears (Ursus americanus Pallas) for 2%. During the 1970s, coyotes killed 98% of all depredated lambs, cougars killed 2%, and bears killed 0%. In addition to the increase in cougar kills, the other change on Cedar Mountain since the 1970s is that California condors (Gymnogyps californianus Shaw) have begun scavenging lamb carcasses. Our results indicate that increasing populations of cougars, black bears, and condors have complicated the task of protecting lambs from predators.
2010-11-01T00:00:00ZRestoring Tallgrass Prairie and Grassland Bird Populations in Tall Fescue Pastures With Winter Grazing
http://hdl.handle.net/10150/642833
Restoring Tallgrass Prairie and Grassland Bird Populations in Tall Fescue Pastures With Winter Grazing
Johnson, Tracey N.; Sandercock, Brett K.
Restoration of grasslands dominated by tall fescue (Schedonorus phoenix [Scop.] Holub) to native tallgrass prairie usually requires burning, herbicides, or reseeding. We tested seasonal grazing by livestock in winter, combined with cessation of fertilization, as a restoration tool for modifying the competitive dynamics among herbaceous plants to restore tallgrass prairie communities in southeastern Kansas. In 2004-2005, we compared responses of grassland plants and birds across a chronosequence of pastures that were winter-grazed from 1 yr to 5 yr. We compared winter-grazed pastures to pastures grazed year-round and to local native prairie remnants as starting and endpoints for restoration, respectively. Abundance of native warm- season grasses increased from 2% to 3% mean relative frequency in pastures grazed year-round to 18% to 30% in winter-grazed pastures, and increased with duration of winter-grazing. Native warm-season grasses accounted for 1-6% of total live aboveground biomass in pastures grazed year-round, 1-34% in winter-grazed pastures, and 31-34% in native prairie remnants. Tall fescue abundance and biomass were similar among grazing treatments, with a trend for tall fescue to be less dominant in winter-grazed pastures. Tall fescue made up 9-40% of total aboveground biomass in year-round grazed pastures and 10-25% in winter-grazed pastures. Grassland birds showed variable responses to winter-grazing. Dickcissels (Spiza americana) and Henslow’s sparrows (Ammodramus henslowii) were more abundant in winter-grazed pastures, whereas eastern meadowlarks (Sturnella magna) and grasshopper sparrows (A. savannarum) had similar abundance in pastures grazed year-round and during winter. Winter-grazing of pastures dominated by tall fescue combined with suspension of nitrogen fertilization could be an effective restoration technique that allows use of prairie rangeland while improving habitat for sensitive grassland birds.
2010-11-01T00:00:00Z