Winterhardiness, Forage Production, and Persistence of Introduced and Native Grasses and Legumes in Southcentral Alaska

This study consisted of four separate field experiments, each of six years duration, conducted at the University of Alaska’s Matanuska Research Farm (61.6oN) near Palmer in southcentral Alaska. Objectives were to compare winterhardiness, forage productivity, and general persistence of introduced grass and legume species, strains, and cultivars from various world sources with Alaska-developed cultivars and native Alaskan species. Twenty-one species of grasses compared (Tables 1 through 4) included eight native to Alaska, four Alaska cultivars, and numerous introduced cultivars and regional strains (one to seven per species) from North America and northern Europe. Legumes included two species of biennial sweetclover and nine species of perennials, six introduced and three native. Each experiment was harvested once near the end of the seeding year and twice annually for five years thereafter

Evaluating Management Options to Increase Roadside Carbon Sequestration

We estimated the amount of carbon sequestered along Montana Department of Transportation (MDT) roads and tested 3 different highway right-of-way (ROW) management techniques to increase carbon stocks. Using Geographic Information System techniques, the total ROW acreage owned by MDT was found to sequester 75,292 metric tons of carbon per year and to consist mostly of grasslands (70%). From 2016-2018 we tested 3 ROW management techniques to increase carbon stocks- increase mowing height, plant woody shrubs, or add legumes to reclamation seed mixes of disturbed soils - at 3 sites (Three Forks [3F], Bear Canyon [BC], and Bozeman Pass [BP]) along Interstate 90 in southwestern Montana. Soil samples generally averaged 0.75–1.5% soil organic carbon (SOC) at the 3F site, 2.5–4% SOC at the BC site, and 1.5–2.5% SOC at the BP site. Average SOC levels were always lower in 2018 than in 2016. Soil respiration rates were generally highest in June or July at the BC site, averaging ~4 μmol CO2 m-2 second-1. Soil respiration rates were lower at the BC site in November 2016, at the BP site in June 2018, and at the 3F site in July 2018 (all ~2–3 μmol CO2 m-2 s-1). Aboveground biomass carbon estimates generally mirrored belowground SOC estimates. Taken together, our findings suggest that of the three treatments implemented (raised mowing height, shrub planting, and disturbance), minimizing disturbance to soils likely makes the greatest contribution to the medium- and long-term carbon-storage potential of these roadside soils

Cattle as Grazing Management and Seed Dispersal Tools for Increasing Native Species Diversity on Great Basin Rangelands

A series of experiments evaluated: 1) the influence of seed intake and gut retention time on seed passage , recovery , and germinability; 2) fecal seeding and broadcast /trampling as techniques to incorporate seeds into a well-established Agropyron desertorum (Fisch.) Schult. stand in Skull Valley , Utah; 3) intensive grazing as a means to reduce Agropyron biomass and increase establishment and survival of seeded species; and 4) the recovery and germinability of seed extracted from dung collected from the field. Two shrubs (Artemisia tridentata Nutt. ssp. wyomingensis Beetle & Young and Atriplex confertifolia Torr. & Frem.), a grass (Elymus elymoides (Raf.) Swezey) , and a forb (Sphaeralcea grossulariaefolia (H. & A.) Rydb.) were selected as representative native species. Holstein heifers were fed 15,000 , 30 ,000 , and 60,000 seeds of Artemisia , Sphaeralcea, and Elymus. Elymus recovery was negatively correlated to seed intake. Sphaeralcea had the highest percentage of recovered, undamaged seed, followed by Elymus and Artemisia. Sphaeralcea and Artemisia seed passage was highest on Day 1 then dropped sharply. Elymus passage and recovery were more consistent through time. Post-passage germjnability was highest for Elymus and Sphaeralcea on Day 1. Artemisia germjnation was neghgible. In the fall seeding, Sphaeralcea emerged in 6% of the subplots (half were volunteers). Overall seedling mortality was 93%. Elymus emerged in 63% of the dung pats, with 86% mortality. No Artemisia emerged. Drought and Anabrus simplex herbivory contributed to low seedling emergence and survival. In April 2003, similar treatments were applied, except Atriplex seed was substituted for Artemisia, and a third treatment was added (broadcast seeding/raking). No emergence was observed. Sphaeralcea had the highest seed recovery from dung collected in the field trials, followed by Elymus, Atriplex, and Artemisia. Sphaeralcea germinability was similar for seeds collected from both trials (11 %) and Elymus germination was highest in the fall seeding (13%). These studies indicate that: 1) physical seed properties (size, shape, density, seed coat) influence seed passage , recovery, and germination; 2) intensive grazing can reduce Agropyron biomass by 50% for 2 years; 3) broadcast/trampling may be effective for Sphaeralcea; and 4) an average-sized dung pat (714 g) may have ample germinable Sphaeralcea and Elymus seeds for plant establishment

Establishment and Persistence of Yellow-Flowered Alfalfa No-Till Interseeded into Crested Wheatgrass Stands

Crested wheatgrass [Agropyron cristatum (L.) Gaertn., A. desertorum (Fisch. ex Link) Schult., and related taxa] often exists in near monoculture stands in the northern Great Plains. Introducing locally adapted yellow-flowered alfalfa [Medicago sativa L. subsp. falcata (L.) Arcang.] would complement crested wheatgrass. Our objective was to evaluate effects of seeding date, clethodim {(E) -2-[1-[[(3-chloro-2-propenyl)oxy]imino] propyl]-5-[2-(ethylthio)propyl]-3-hydroxy-2-cyclohexen-1-one} sod suppression, and seeding rate on initial establishment and stand persistence of Falcata, a predominantly yellow-flowered alfalfa, no-till interseeded into crested wheatgrass. Research was initiated in August 2008 at Newcastle, WY; Hettinger, ND; Fruitdale, SD; and Buffalo, SD. Effects of treatment factors on plant frequency during initial establishment were influenced by site environments. Late summer and spring were suitable seeding dates. Clethodim sod suppression increased seedling frequency in most cases. Seedling frequency increased as seeding rate increased from 0.56 to 7.84 kg pure live seed (PLS) ha–1. Specific seeding dates, clethodim sod suppression, and high seeding rates did not greatly improve initial establishment when site environments were poor. Residual effects of seeding date and sod suppression post establishment were not significant at most locations, but seeding rate effects were evident. Initial establishment and persistence of Falcata alfalfa was successful at Newcastle, indicating that interseeding in late summer or spring using low seeding rates (≤3.36 kg PLS ha–1) without clethodim can be effective. Assessing grass canopy cover, soil texture, and management (e.g., haying) is necessary to determine the suitability of crested wheatgrass sites for interseeding

Summaries of Forage Research

Identification of alternative crops capable of producing high quality forage in conditions not conducive for alfalfa or perennial grass production would be desirable. The production of high quality forages in large quantities is the basis of any successful dairy enterprise. This will reduce the necessity of purchasing expensive supplemental grain and protein sources. Certain warm-season annual grasses and legumes, when harvested at the proper stage of maturity, are capable of producing high quality forage in large quantities where conditions are not suitable for alfalfa production. The objects was to evaluate the forage production and chemical composition at two cutting dates of four warm-season annual grasses and two annual legumes at two locations. Four grasses (German millet, Siberian millet, Sudangrass, and teff) and an annual legume (cowpea) were grown at two locations (Brookings and Highmore, SD) in the summer of 1986. Forage were harvested at two dates, 36 and 57 days after planting at Brookings and 41 and 57 days after planting at Highmore, to evaluate changes in nutrient composition as affected by maturity. Forage material was harvested, weighed, and analyzed for dry matter, crude protein, neutral-detergent fiber (NDF), acid-detergent fiber (ADF), lignin, and in vitro dry matter digestibility (IVDMD). Chickpeas were also included in this study, but plots were completely destroyed by Ascochyta blight

Integrated Pest Management on Rangeland: State of the Art in the Sagebrush Ecosystem

Several sagebrush communities represent optimum levels of negative development plant productivity for certain peculiar sites, and therefore should be managed for their preservation. Other sagebrush communities may be profitably modified to favor forage species that are more palatable to domestic livestock. Modification techniques can range from subtle (i.e., grazing strategies) to tracematic (i.e., brush removal and revegetation), and an associated spectrum of management tactics are described. Interrelationships between and problems associated with management of forage resources, management of weeds, and management of insects (including grasshoppers, black grass bugs, and beneficial insects) are discussed. Economical analyses, the role of modeling as a management tool, and impacts of management tactics on wildlife and non-target species also are discussed

Growing Wild: Crested Wheatgrass and the Landscape of Belonging

Crested wheatgrass arrived in North America at the turn of the twentieth century through the foreign plant exploration missions sponsored by the United States Department of Agriculture. During the first two decades of the new century, scientists tested the grass at agricultural experiment stations. They determined it was useful for grazing and particularly valuable because it could grow in drought conditions with little or no care and would continue to produce high quality feed even after several years of heavy use. Beginning in the 1930s federally sponsored land utilization and agricultural adjustment programs sponsored the use of crested wheatgrass for soil conservation and weed control. The grass protected the soil on the land that had been entered into the acreage reserves and the conservation reserves programs of the federal soil bank. Also in the late 1930s and through the 1960s, rangeland managers used crested wheatgrass to improve forage productivity on public lands that were used for grazing. By the 1970s somewhere between 12 and 20 million acres of crested wheatgrass grew in North America in eleven western states, and in Saskatchewan and Alberta. By 1980 attitudes about agriculture and wilderness had changed in the United States and land management was focused on multiple uses and on protecting ecosystems and native species. Attitudes about grazing and agricultural landscapes had changed and many preferred nonagricultural landscapes and land uses. As a result, crested wheatgrass went from being considered one of the most valuable plants in North America to being considered an invasive weed, in some quarters. Debates in the last 25 years have tried to determine if, where, and how crested wheatgrass belongs in North America. This thesis explains the discourses, or interest groups, that are participating in the current conversation. One impulse is to use empirical evidence to determine whether or not introduced plants like crested wheatgrass belong, but the main contention of this thesis is that empirical studies alone will always be insufficient measures because belonging is also a subjective and experientially or emotionally derived measure

Assessing Post-Fire Revegetation Efforts in Box Elder County, Utah, Using the Rangeland Analysis Platform

After fires occur in western rangelands, land management agencies commonly perform vegetation treatments and reseeding projects. The West Box Elder Coordinated Resource Management Group expressed concern regarding the difficult process of determining outcomes from the many post-fire revegetation projects undertaken on rangeland of Box Elder County, Utah. This research attempted to compile and clarify the fire and treatment history of the county and produce an assessment of the outcomes from each unique post-fire treatment in West Box Elder County. Also produced was a database of post-fire revegetation outcomes in published literature. Unique treatment polygons were identified and then subset according to the resistance/resilience ranking of the ecosystem where they were found. To assess treatment outcomes, the Rangeland Analysis Platform was used to show trends in different types of vegetation from satellite imagery. Formal effect size analyses were performed with the outputs of the Rangeland Analysis Platform. Effect size analyses measures the strength between to variables, in this case I measured what vegetation looked like before and after the treatments. Mild successes in perennial establishment occurred across treatment types. Annual cover increased or was more closely dependent on pretreatment levels than treatment type. My results also indicate that time to recovery after fire may be longer than 15-years, especially when evaluating shrub response to post-fire treatments. My analysis reemphasized that, annual, perennial, and shrub responses to treatments are highly variable and depend on many factors besides treatment method and R&R classification alone. A database of publications outlining post-fire revegetation outcomes was also compiled. This database was designed to help managers refamiliarize with and discover new literature regarding post-fire restoration techniques and outcomes. Literature focusing on specific outcomes of post-fire revegetation across rangelands of the great basin were assembled into this database. Categories of key words were assembled and used to describe each study and help facilitate specific managers queries

Competitive Interaction between Crested Wheatgrasses and Cheatgrass

Current revegetation practices in the lntermountain West include the use of Nordan (Agropyron desertorum) and Hycrest (A. cristatum x desertorum) crested wheatgrass on rangeland susceptible to cheatgrass (Bromus tectorum) invasion, although little quantitative data exists that compares their competitive abilities. We evaluated both the competitive ability of Hycrest and Nordan in two-species mixtures with cheatgrass, and evaluated seedling establishment characteristics for all three species in a greenhouse study. Linear and nonlinear models were developed for a range of densities for each species to predict median above-ground biomass and tiller numbers. In both experiments, increasing Hycrest and Nordan densities reduced their own biomass and tiller production while cheatgrass biomass and tiller production was not influenced. However, increasing cheatgrass densities reduced both Hycrest and Nordan biomass and tiller production, as well as its own biomass and tiller production. Examination of trends in competition indices, such as relative resources totals, substitution rates and perceived densities indicated that as seedlings, Hycrest was a better competitor with cheatgrass than Nordan at lower crested wheatgrass densities (130 plants/m2 ). Results from this experiment indicate that Hycrest is a better competitor than Nordan with cheatgrass and suggest that seeding Hycrest at lower densities than currently recommended may optimize its seedling growth when competing with cheatgrass. Future research concerning competition in these species using similar designs should focus on competition in successive years after establishment and on field experiments to verify these results