Download or read book Downy Bromegrass Bromus Tectorum L written by Richard S. Fawcett and published by . This book was released on 1984 with total page 2 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Downy Bromegrass Bromus Tectorum L written by V.M. Jennings and published by . This book was released on 1977 with total page 2 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Chemical Control of Downy Brome grass Bromus Tectorum L in an Established Alfalfa Field written by Mark G. Wiltse and published by . This book was released on 1952 with total page 94 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Interference Growth and Physiological Respon s e of Downy Brome Bromus Tectorum and Medusahead Taeniatherum Asperum written by Abdullah Juma Al-Dakheel and published by . This book was released on 1986 with total page 332 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Management of Downy Brome bromus Tectorum in Native Grasslands written by Saskatchewan Watershed Authority and published by . This book was released on 2006* with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Interference Growth and Physiological Respone of Downy Brome Bromus Tectorum and Medusahead Taeniatherum Asperum written by Abdullah Juma Al-Dakheel and published by . This book was released on 1986 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Growth, competitive performance, and physiological response of the introduced annuals downy brome (Bromus tectorum L. ) and medusahead (Taeniatherum asperum (Sim.) Nevski) were compared under various environmental conditions in growth chambers and greenhouses. Seeds of both species were collected near Verdi, Nevada. Effects of soil moisture on growth, resource partitioning, photosynthesis, stomatal conductance, and transpiration rates were characterized for both species. Competitive interactions between the species were assessed in replacement series experiments. Under unlimited moisture, mean dry matter production and leaf area were greater in downy brome than medusahead. Height and root/shoot ratios were higher in medusahead or similar to those of downy brome. Mean values of relative growth rate (RGR) and net assimilation rate (NAR) over the entire growing period were similar between the species. RGR was significantly higher in downy brome o f 40 d age, and higher in medusahead of 40 d age. Rate of biomass allocation to leaf area (LAR) correlated best with dry matter production in both species. LAR was higher in downy brome than medusahead on most sample dates. Moisture stress reduced height, leaf development, and consequently biomass production in both species. Downy brome maintained higher dry matter production than medusahead when moisture was limited, due to higher LAR in downy brome. Stomatal conductance and transpiration rates were higher in medusahead than downy brome throughout the growing period. Under moisture stress, both species were similar in conductance and transpiration rates. Carbon fixation response (measured by IRGA in laboratory cuvettes) to light throughout the growing period were similar for the two species, regardless of moisture conditions. Moisture stress reduced photosynthesis in each species by > 50%. Competitive performance in mixtures was related to the maximum relative growth rate (Rmax) attained during early plant development. With unlimited moisture, downy brome had higher Rmax and LAR than medusahead. These differences gave competitive superiority to downy brome in interspecific mixture. Under moisture stress, both species were similar in Rmax and in general competitive performance. Effects of three temperature regimes and two moisture levels on growth, interference, and photosynthesis response in downy brome and medusahead were investigated in growth chamber study. Plants were grown separately and in intra- and interspecific pairs. Optimum temperature for growth of both species was the moderate temperature regime (24/11 C ). At this moderate regime, medusahead yield was higher than that of downy brome. Downy brome yield was less affected by temperature extremes and was significantly higher than that of medusahead at these extremes. Moisture limitation reduced yield in both species at all temperature regimes. Variation in performance between species at each temperature regime was closely related to photosynthetic response and pattern of resource allocation. In mixtures, downy brome had higher yield than medusahead at all temperature regimes. At low temperature (16/5C), both species were competitively similar. The competitive advantage of downy brome over medusahead increased with increasing temperature and was most profound at high temperature (32/16C). In limited moisture, downy brome maintained higher yield than medusahead in pure stands and mixtures. Species competitive performance in mixture also correlated with photosynthesis and resource allocation. Effects of nitrogen and phosphorus supply on growth and interference between downy brome and medusahead were studied in sand culture using a modified replacement series experiment in the greenhouse. Three levels of nitrogen and phosphorus were applied in all possible combinations. Height, number of leaves, and biomass production were reduced in both species in response to nutrient reduction. Downy brome had higher dry matter production than medusahead at high concentrations of nitrogen or phosphorus or when both nutrient elements were present. When either nutrient was lacking, yields of both species were similar. Nitrogen deficiency was more influential on yield reduction than phosphorus in both species. In mixtures, downy brome was highly competitive at high concentrations of N and P. At lower levels of N and P, the species performed as competitive equals. Thus, early patterns of resource allocation and high growth rates in downy brome enable that species to outperform medusahead at high nutrient concentrations. Findings of these studies were discussed in relation to the distribution of the two species in the field.

Download or read book Response of Downy Brome Bromus Tectorum and Kentucky Bluegrass Pao Pratensis to Primisulfuron written by Paul E. Hendrickson and published by . This book was released on 1998 with total page 62 pages. Available in PDF, EPUB and Kindle. Book excerpt: Glasshouse and growth-chamber experiments were conducted to evaluate primisulfuron phytotoxicity and the influence of adjuvants on downy brome and Kentucky bluegrass. GR50 (50% growth reduction) values were 0.97 ± 0.57 and 8.07 ± 1.85 g/ha for downy brome and Kentucky bluegrass, respectively. Primisulfuron was applied to downy brome and Kentucky bluegrass at 3 placement sites; foliar, soil, and foliar plus soil. Foliar or foliar plus soil applications were more effective at reducing downy brome dry weights than the soil application of primisulfuron, while Kentucky bluegrass was injured more from the soil or foliar plus soil applications than from the foliar application of primisulfuron. Primisulfuron at 5 g/ha applied alone reduced downy brome dry weights by 5%, whereas, when an adjuvant was added, dry weights were reduced by 52 to 83%. Primisulfuron was more phytotoxic to downy brome at alternating temperatures of 8-16 C and 16-24 C than at 0-8 C. Phytotoxicity of primisulfuron was less when downy brome plants were stressed for soil moisture after herbicide treatments than when the plants were not stressed or only stressed before treatment.

Download or read book A Novel Method for Removing Downy Brome from Reclamation Seed written by William Rose and published by . This book was released on 2015 with total page 63 pages. Available in PDF, EPUB and Kindle. Book excerpt: Disturbance increases infestation potential for weeds such as downy brome (Bromus tectorum ). Downy brome often contaminates seed used in reclamation efforts. Because downy brome germinates more rapidly and at colder temperatures than many native grasses, it may be possible to remove downy brome from desirable seed lots by exploiting germination differences. We initiated a sequence of experiments where native grass and downy brome seeds underwent a wet germination treatment followed by a drying period. During the first experiment, we evaluated three different germination temperatures (3, 6, and 12°C) for 20-days. Downy brome germinated earlier and more rapidly than native species at all temperatures. No downy brome survived the 6°C and 12°C treatments. Survival was lower for all treated seeds compared to nontreated seeds except blue grama at 3°C. We held temperature constant (6°C) in the second experiment and compared four germination treatment durations (8, 10, 12, and 14 days). Blue grama germinability was unaffected by treatment duration in the second experiment, and thickspike wheatgrass was only reduced by the 14-day treatment. Downy brome mortality was limited in the second experiment and ranged from 4.5 to 51% depending on treatment duration. In the third experiment, we compared six drying treatments after a constant germination temperature (6°C) and duration (12 days). Blue grama and thickspike wheatgrass had the highest survival compared to downy brome. Drying seeds in commercial dryers at 30°C and 60°C severely reduced downy brome survival while maintaining high blue grama survival. Results were similar for thickspike wheatgrass in the 30°C dryer.

Download or read book The Brome grasses of Wyoming written by Aven Nelson and published by . This book was released on 1901 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Downy Brome Control Strategies for Southwestern Saskatchewan written by and published by . This book was released on 1993 with total page 125 pages. Available in PDF, EPUB and Kindle. Book excerpt: Downy brome (Bromus tectorum L.) has spread throughout southwestern Saskatchewan over the last 15 years to become a serious weed in various crops, pasture, and rangeland. This report presents results of field trials conducted over three years to evaluate herbicides, rotations, and intensive grazing as management tools for controlling downy brome. The investigators evaluated 26 herbicides for downy brome control and crop tolerance in winter wheat, fall rye, fallow, alfalfa, and grass hayland. They tested the compounds in isolation, as tank mixes, and with various adjuvants. Minor use proposals were submitted for five of the herbicides evaluated. The tests included evaluation of growth, seed production, and soil seedbank of downy brome in various crop rotations, and assessment of the effect of intensive spring grazing with cattle in reducing downy brome seed production.

Download or read book Adaption to Climate Change and Small Grain Production Systems by Bromus Tectorum written by Nevin Craig Lawrence and published by . This book was released on 2015 with total page 150 pages. Available in PDF, EPUB and Kindle. Book excerpt: Bromus tectorum (downy brome) is an invasive winter annual grass species naturalized throughout western North America. Within the small grain production region of the Pacific Northwest (PNW) downy brome is a ubiquitous and competitive weed. Previous research has documented regional specificity of downy brome phenotypic development, while considerable variation in phenotypic development has been noted between regions. In 2011 and 2012 130 downy brome accessions were collected from across the PNW small grain production region. A genotype-by-sequencing approach was employed to call molecular markers, generate population genetic statistics, and classify 88 of the 130 downy brome accessions into genetically similar clusters. Individuals were assigned to one of six genetic clusters using discriminant analysis of principal components using 384 single-nucleotide polymorphisms. Accessions were transplanted to three common garden field sites to document and model the timing of development. The timing of development stages was modeled against cumulative growing-degree-days (GDD) to develop herbicide application thresholds to aid in control of downy brome within small grain fields. The estimate for mature seed production varied from May 18th to June 20th depending upon the location of the common garden. Earlier production of mature seed was observed following more severe winters compared to mild winters, implying a role of vernalization regulating the timing of development. Greenhouse experiments were initiated to characterize the response of early, intermediate, and late-to-flower downy brome accessions to various vernalization treatments and quantify expression of Brachypodium distachyon gene vernalization 1 (BdVRN1). Downy brome flowering in response to vernalization treatments was linked to the expression of BdVRN1, implying the molecular controls of flowering in downy brome are similar to the controls of other temperate grass species. Downscaled climate modeling was paired with Global Climate Change models to project downy brome development thresholds under future climate scenarios. Downy brome development is anticipated to advance 16 to 34 days across the small grain production region of the PNW. The earlier development of downy brome will require earlier control inputs, which may conflict with earlier rainfall projected under future climate scenarios.

Download or read book Control of Downy Brome in Alfalfa and Related Studies written by Victor Friedrich Bruns and published by . This book was released on 1959 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Invasive Plants of California s Wildlands written by Carla C. Bossard and published by Univ of California Press. This book was released on 2000 with total page 366 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Invasive nonnative plants threaten native species with habitat loss, displacement, and severe population declines, thus seriously reducing biodiversity. Invasive Plants of California's Wildlands is a tremendous source for land managers and others who are interested in protecting the rich natural heritage of California and surrounding states."--John C. Sawhill, President and CEO, The Nature Conservancy

Download or read book The Beet Leafhopper written by James Robert Douglass and published by . This book was released on 1954 with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Weedy Bromegrasses and Their Control written by and published by . This book was released on 1984 with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Historical Common Names of Great Plains Plants Volume I Historical Names paperback written by Elaine Nowick and published by Lulu.com. This book was released on 2014-10 with total page 505 pages. Available in PDF, EPUB and Kindle. Book excerpt: Containing thousands of entries of both vernacular and scientific names of Great Plains plants, the literature that informs this exhaustive listing spans nearly 300 years. Author Elaine Nowick has drawn from sources as diverse as Linnaeus, Lewis and Clark, and local university extension publications to compile the gamut of practical, and often fanciful, common plant names used over the years. Each common name is accompanied by a definitive scientific name with references and authority information. Interspersed with scientifically-correct botanical line drawings, the entries are written in standard ICBN format, making this a useful volume for scholars as well as lay enthusiasts alike. Volume 1 presents, in alphabetical order, all the historical common names of plants recorded in Great Plains flora, herbaria, and botanical collections, together with the scientific names of species to which those common names have been applied.

Download or read book Ecology in Agriculture written by Louise E. Jackson and published by Academic Press. This book was released on 1997-09-14 with total page 487 pages. Available in PDF, EPUB and Kindle. Book excerpt: Agricultural crops are prominent features of an increasing number of variously perturbed ecosystems and the landscapes occupied by these ecosystems. Yet the ecology of agricultural-dominated landscapes is only now receiving the scientific attention it has long deserved. This attention has been stimulated by the realization that all agriculture must become sustainable year after year while leaving nearby ecosystems unaffected. Ecology in Agriculture focuses exclusively on the ecology of agricultural ecosystems. The book is divided into four major sections. An introduction establishes the unique ties between agricultural and ecological sciences. The second section describes the community ecology of these sorts of ecosystems, while the final section focuses on the processes that operate throughout these agricultural landscapes. - Contains an ecological perspective on agricultural production and resource utilization - Includes in-depth reviews of major issues in crop ecology by active researchers - Covers a range of topics in agricultural ecophysiology, community ecology, and ecosystems ecology - Provides examples of ecological approaches to solving problems in crop management and environmental quality