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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Application of hyperspectral remote sensing in detecting and mapping Sericea lespedeza in Missouri

Zhou, Bo, January 2007 (has links)
Thesis (M.A.)--University of Missouri-Columbia, 2007. / The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on November 9, 2007) Includes bibliographical references.
2

Integrative Management of Lespedeza cuneata in Prairie Restorations

Shupert, Lindsay Anne 01 May 2016 (has links)
Background: Lespedeza cuneata is a perennial invasive legume native to Asia that is common across grasslands in the eastern half of the United States and parts of Canada. The competitive nature and limited palatability of L. cuneata for grazers in the tallgrass prairie has made it an undesirable and invasive weed. Objectives: This study was conducted to investigate an invasive species management plan for restored grasslands and prairie areas. Methods: Study plots (n=144) for experiment 1 (summer treatment) were established at Crab Orchard Wildlife Refuge in Jackson County Illinois in August of 2012 and were situated to contain infestations of the target species. Two herbicides, in five concentrations were applied in August of 2012. A native seed mix was added to a portion of the summer plots later, in February of 2013. These treatments were assessed in June and August of 2013 to determine herbicide effects on stem count and percent cover of L. cuneata, along with the composition and percent cover of other species present. Spring herbicide applications (n=18) for experiment 2 were established, assessed for L. cuneata cover and density, and treated with two herbicide treatments in May of 2013. Spring treatments were identical to existing plots and were re-assessed in August 2013 to determine species composition and the abundance of L. cuneata. Seed was not added to these plots. Analysis: Mixed Model analysis by site was performed to test the effect of herbicide and seeding treatments on L. cuneata for both experiments 1 &2. The summer plots were also tested for effects on other plant groups. A repeated measures PERMANOVA along with ANOSIM and PERMADISP was performed to assess community composition response to seeding and herbicide treatments in the summer plots. Results: Abundance of L. cuneata was reduced 67 to <90% following herbicide treatment in Experiments 1 and 2. There were no differences in the effectiveness of herbicide treatments in in experiment 1, sites 1 &3, and in experiment 2. Supplemental seeding in the summer plots did not reduce the abundance of L. cuneata consistently across sites. Conclusion: Considerable short-term control of the target species was achieved in both the summer and spring plots, providing a window of opportunity for the imposition of additional methods of control. However, data from the summer plots suggest recovery of L. cuneata some sites, indicating further control would be necessary, with potentially the addition of other control methods or site alterations.
3

Restoration of tallgrass prairie degraded by the noxious weed sericea lespedeza

Gatson, Garth Arnold January 1900 (has links)
Master of Science / Department of Animal Sciences and Industry / K C Olson / The largest intact remnant of the tallgrass prairie, the Flint Hills ecoregion, is currently under threat from the invasive weed sericea lespedeza (Lespedeza cuneata [Dumont] G. Don; SL). The objectives of this research were to evaluate the efficacy of late-season prescribed burning and fall herbicide application, alone and in concert, for comprehensive control of sericea lespedeza and to assess their broader treatment impacts on native plant communities. A 31-ha native tallgrass pasture with a light to moderate infestation of SL was divided into 16 subunits for this experiment. Each subunit was randomly assigned to 1 of 4 treatments: negative control, spray-only, burn-only, or burn-plus-spray. A prescribed burn was conducted on burn-only and burn-plus-spray subunits in early September 2016. Following the re-emergence of SL, spray-only and burn-plus-spray subunits received a broadcast application of metsulfuron methyl (Escort XP, DuPont, Wilmington, DE) at a rate of 70.1 g ˖ ha⁻¹ in late September. Frequency and vigor of SL, total forage biomass, soil cover, and plant species composition were measured along permanent 100-m transects in each subunit prior to treatment application and again 12 mo later, in 2017 (i.e., 1 YAT). In 30 x 30-cm plots at 1-m intervals along each transect, the presence or absence of SL was noted. Where SL was present, crown maturity and maximum stem length of the SL plant nearest to the transect were recorded. Presence of multiple stems in plots was also recorded. Prior to treatment application, SL comprised 1 ± 2.0% of total basal cover and was not different between treatments (P = 0.38). One YAT, SL was more abundant (P ≤ 0.02) in negative control subunits than in spray-only, burn-only, or burn-plus-spray subunits, which were not different (P ≥ 0.95) from one another. Aerial frequency of SL, abundance of mature SL crowns, and incidence of plots with multiple SL stems were greatest (P ≤ 0.03) for negative controls, although not different (P ≥ 0.50) between the other 3 treatments. The change in forage biomass production 1 YAT did not differ (P = 0.16) between treatments. A tendency (P = 0.06) for a shift from litter cover to bare soil was noted when the spray-only, burn-only, and burn-plus-spray treatments were compared to the negative control. Graminoid basal cover was greater (P < 0.01) in the spray-only and burn-plus-spray treatments than in the negative-control and burn-only treatments 1 YAT. Conversely, forb basal cover was less (P = 0.01) in spray-only and burn-plus-spray treatments than in negative-control and burn-only treatments. The evenness component of diversity decreased in the burn-plus-spray treatment relative to the negative control (P ≤ 0.01). These data indicate that each of these strategies were effective in reducing SL populations. Although late-summer prescribed burning produced no detected negative responses within the native plant community, fall herbicide application, alone or in conjunction with prescribed burning, resulted in collateral damage to forb populations. A late-summer prescribed burn alone is recommended for low-cost comprehensive control of a light to moderate sericea lespedeza infestation.
4

Herbivory habits of beef cows grazing native range infested by sericea lespedeza

Preedy, Garrett William January 1900 (has links)
Master of Science / Department of Animal Sciences and Industry / KC Olson / Our objective was to determine the effects of supplemental corn steep liquor (CSL) on voluntary selection of sericea lespedeza (SL) by beef cows grazing native tallgrass range. Dietary botanical composition of cows (n = 145; initial BW = 579 ± 91 kg) was evaluated during a 150-d grazing period (5/1 to 10/1). Native pastures (n = 9; 50 ± 17 ha) infested by SL (average SL biomass = 37% of total forage biomass) were assigned randomly to 1 of 2 treatments: grazing by unsupplemented cows or grazing by cows supplemented with CSL (1.79 kg DM • cow-1 • d-1; 45% DM, 34% CP). Cows were assigned randomly to treatment and pasture (stocking rate = 0.5 ha/AUM). Concentration and protein-binding capacity of condensed tannins (CT) in SL were measured monthly. Fecal samples were collected from each cow on 6/1, 7/1, 8/1, 9/1, and 10/1. Herbivory of SL was estimated along line transects in October. Plant fragments in fecal samples were quantified via a microhistological technique; fragment prevalence in fecal material was assumed to equal botanical composition of the diet. Concentration and protein-binding capacity of CT in SL were greatest (P < 0.01) on 8/1 and 9/1, respectively. The proportion of individual SL plants showing evidence of herbivory tended to be greater (P = 0.09) on pastures grazed by supplemented cows compared to pastures grazed by unsupplemented cows (94 vs. 80% of SL stems, respectively). Prevalence of SL in beef cow diets was influenced (P < 0.01) by CSL supplementation and by month. Prevalence of SL in beef cow diets was not different (P ≥ 0.35) between treatments when concentration and protein-binding capacity of CT were relatively low (6/1, 7/1, and 10/1). In contrast, supplemented cows selected more (P < 0.01) SL than unsupplemented cows when concentration and protein-binding capacity of CT were greatest (8/1 and 9/1). We interpreted these data to suggest that voluntary selection of SL by beef cows was inversely related to concentration of CT; moreover, supplemental CSL stimulated voluntary selection of SL during periods of high CT concentration. Supplemental CSL did not influence selection of other plant species that were monitored.
5

Short-term intensive management of high densities of the invasive plant sericea lespedezea /

Cornell, Jack E., January 1900 (has links)
Thesis (M.S.)--Missouri State University, 2008. / "May 2008." Includes bibliographical references (leaves 39-42). Also available online.
6

Botanical composition of yearling-steer and mature-ewe diets in the Kansas Flint Hills

Sowers, Consuelo Ann January 1900 (has links)
Master of Science / Department of Animal Sciences and Industry / K C Olson / Eight native tallgrass pastures infested with sericea lespedeza (initial basal frequency = 2.9 ± 2.74%) were grazed by yearling beef steers (n = 279 / yr; 1.1 ha / steer) from 15 April to 15 July for 2 grazing seasons. Subsequent to steer grazing, mature ewes (n = 813 / yr) were allowed to graze 4 of the 8 pastures (0.15 ha / ewe) from 31 July to 1 October. Remaining pastures were rested until the subsequent April. Animals were allocated randomly to pastures annually; grazing treatments remained fixed for the 2-yr experiment. Four permanent 100-m transects were laid out in a north-south gradient in each pasture. Beginning 1 May, steer diet composition was monitored by collecting 5 fresh fecal pats along each transect at 2-wk intervals until steers were removed on 15 July. Fecal pats were dried and ground individually and then composited by weight within transect. Twenty-five mature ewes from each pasture were randomly selected to monitor diet composition. On 15 August and 15 September, ewes were gathered and restrained; fecal grab samples were then collected from the individuals selected for diet composition analysis. Microhistological analysis was conducted on steer fecal composites and fecal samples from individual ewes, using pure samples of 17 predominant grass, forb, and browse species from the experimental site as reference standards. Fecal and standard samples were prepared for microhistological analysis and viewed using a compound microscope at 100x magnification. Botanical composition of pastures was measured in October and compared with botanical composition of yearling beef steer and mature ewe diets. Diet selection exercised by yearling steer and mature ewes was evaluated using Kulcyznski’s Similarity Index. Proportions of bare soil, litter cover, and total basal vegetation cover did not differ (P ≥ 0.38) between pastures for either steer or sheep diet evaluations. Similarly, basal cover of the 17 plants selected as microhistological standards did not differ (P ≥ 0.07) between pastures for either steer or sheep diet evaluations. The proportions of total graminoids and total forbs and forb-like plants in the diets of grazing steers were not different (P = 0.37) between sampling periods and were interpreted to indicate steer diets were strongly dominated by graminoids (≥ 88.4% of diets). Yearling beef steers consistently exhibited strong preference (i.e., ≤ 6% similarity with pasture composition) for Bouteloua gracilis, Bouteloua dactyloides, Dalea purpurea, and Liatris punctata, whereas they strongly avoided Lespedeza cuneata and Symphyotrichum ericoides. The proportions of total graminoids and total forbs and forb-like plants in the diets of grazing ewes were not different (P = 0.67) between sampling periods and were interpreted to indicate that mature ewes selected consistent proportions of grasses and forbs over time (average = 58 and 42% of diets for grasses and forbs, respectively). Mature ewes consistently exhibited strong preference (i.e., ≤ 10% similarity with pasture composition) for Bouteloua gracilis, Bouteloua dactyloides, Dalea purpurea, Liatris punctata, Vernonia baldwinii, and Ambrosia artemisiifolia. None of the 17 microhistological reference standards were consistently avoided by ewes.
7

Seed Priming and Smoke Water Effects on Germination and Seed Vigor of Selected Low-Vigor Forage Legumes

Smith, Thomas M. 09 January 2007 (has links)
A commercial solid matric priming method and an osmotic priming method were used to measure seed priming responses of birdsfoot trefoil, kura clover, and sericea lespedeza. Differences were not observed using standard germination tests, but both priming methods show potential for increased germination rate (P>0.05). Conflicting results for matric and osmotic priming were found in terms of seed storage potential after priming, with matric primed seeds showing higher (P<0.05) germination after accelerated aging and osmotic primed seeds showing significant lower germination(P<0.01). Birdsfoot trefoil benefited from priming, but responses varied by priming treatment, while kura clover showed less response to both priming treatments. In a field study comparing matric primed vs. unprimed seedling emergence, matric priming effects were small and these data suggest that solid matrix priming may be unlikely to improve the field establishment of either species. Aqueous smoke solutions were also tested for effect on seed germination. Differences in final germination percent due to solution type (after exposure to liquid smoke solutions for 10- or 45-min) were not observed. Highest concentration of the 10-min solution treatment reduced (P<0.05) birdsfoot trefoil germination. Greater germination was observed only for 'Perfect Fit' kura clover treated with low or intermediate concentrations of either solution. High concentrations of 10-min smoke water increased time to 50% germination (T50) for all seeds, but some reduction in T50 occurred for kura clovers treated with low (5%) solution concentrations. The 45-min treatments had little effect on germination rates. Applying aqueous smoke solution to seeds at germination did not improve germination responses of these forage legume species. / Master of Science
8

Effects of prescribed fire timing on vigor of sericea lespedeza in the Kansas Flint Hills

Alexander, Jonathan Andrew January 1900 (has links)
Master of Science / Department of Animal Sciences and Industry / K C Olson / We evaluated effects of annual, prescribed burning on vigor of the noxious weed, sericea lespedeza (Lespedeza cuneata; SL) in native tallgrass prairie over a 4-yr period. We hypothesized that annual prescribed burning conducted during the growing season would selectively pressure SL, whereas locally-conventional, dormant-season prescribed burning would have no effect on SL. A 50-ha native tallgrass pasture infested with SL (initial basal frequency = 2 ± 1.3%, initial aerial frequency = 36 ± 3.4%) was used for our study. It was divided along watershed boundaries into 9 fire-management units (5 ± 2.6 ha) for this experiment. Burn units were assigned randomly to 1 of 3 prescribed-burning times (n = 3 / treatment): early spring (1 April; EARLY), mid-summer (1 August; MID), or late summer (1 September; LATE). Forage biomass, SL aerial frequency, SL stem length, SL seed production, soil cover, and plant species composition were measured along single, permanent 100-m transects in each burn unit. Treatment and measurement date influenced forage biomass and SL stem length (treatment × time). Forage biomass was not different (P ≥ 0.43) between treatments on 17 July; however, forage biomass was greater (P < 0.01) in EARLY than MID and greater in MID than LATE on 10 October. Maximum stem length of SL was less (P ≤ 0.02) in MID and LATE than in EARLY on 17 July and on 10 October. Aerial frequency of SL was least (main effect – P < 0.01) in LATE, intermediate in MID, and greatest in EARLY, whereas basal frequency of SL was less (P < 0.01) in MID and LATE compared with EARLY. Whole-plant dry weight and seed production of SL at dormancy were greatly diminished (P ≤ 0.02) in MID and LATE compared with EARLY. Occurrence of bare soil, litter cover, and total basal plant cover were not different (P ≥ 0.21) between treatments. Similarly, basal cover of grasses, forbs, and shrubs were not different (P ≥ 0.24) between treatments. We interpreted these data to indicate that annual prescribed burning during the growing season had strong suppressive effects on SL compared to locally-conventional, early-season prescribed burning and produced no apparent detrimental effects on soil cover or non-target plant species. Post-fire regrowth was sufficient to prevent erosion and soil-moisture loss during the subsequent dormant season and would have allowed light to moderate grazing during the ensuing winter. Key words: Lespedeza cuneata, prescribed fire, range improvement
9

Sericea lespedeza (Lespedeza cuneata): seed dispersal, monitoring, and effect on species richness

Blocksome, Carolyn E. January 1900 (has links)
Doctor of Philosophy / Department of Agronomy / Walter H. Fick / Sericea lespedeza [Lespedeza cuneata (Dumont) G. Don] is a rangeland weed of the tallgrass prairie of Kansas. Experiments were carried out during the 2001-2003 growing seasons (June-November) to examine the relationship between sericea lespedeza and other rangeland species, wildlife use and dispersal of sericea lespedeza propagules, and the relationship between sericea lespedeza stubble height and utilization by livestock. Sericea lespedeza cover was positively correlated with violet lespedeza (r=0.25) [Lespedeza violacea (L.) Pers.], heath aster (Aster ericoides L.) (r=0.23) and total forb cover (r=0.56). Sericea lespedeza composition was negatively correlated with big bluestem (Andropogon gerardii Vitman.) (r=-0.27) and sideoats grama [Bouteloua curtipendula (Michx. Torr.)] (r=-0.27) composition and positively correlated with western ragweed (Ambrosia psilostachya D.C.) (r=0.21) and violet lespedeza (r=0.36) composition. Sericea lespedeza density was inversely related to forb species richness on all sites. On half the sites, there was also an inverse relationship between grass species richness and sericea lespedeza density. Grazed sites had less difference in grass species richness between high and low levels of sericea lespedeza densities. There was no evidence of an ecological threshold to the detriment of species richness with increasing sericea lespedeza density. Cattle digestive processes did not affect sericea lespedeza germination. Quail digestive processes enhanced germination of the few seeds that were excreted. Quail diet selection was investigated with a field study. Five out of 49 crops collected contained seed classified as sericea lespedeza. None of these seeds germinated in the greenhouse. Both cattle and quail could potentially disperse sericea lespedeza seed, but voluntary consumption appears to be low for both species, at least during November when other food is available. An height-weight table estimating percent utilization for various grazed and ungrazed heights of sericea lespedeza was constructed. Coefficient of determination values were greater than 0.85 between plant height and weight, indicating that the heightweight method was appropriate for estimating sericea lespedeza utilization. Using additional regression analysis, a chart for estimating forage from percent of plants grazed was constructed.

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