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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.
301

Johnson Grass Control

Heard, H. C. 01 December 1917 (has links)
This item was digitized as part of the Million Books Project led by Carnegie Mellon University and supported by grants from the National Science Foundation (NSF). Cornell University coordinated the participation of land-grant and agricultural libraries in providing historical agricultural information for the digitization project; the University of Arizona Libraries, the College of Agriculture and Life Sciences, and the Office of Arid Lands Studies collaborated in the selection and provision of material for the digitization project.
302

Bermuda Grass insect Control

Tickes, B., Rethwisch, M. 09 1900 (has links)
No description available.
303

Grass Seed Production

Hamilton, Louis P., Wooton, W. M. 07 1900 (has links)
No description available.
304

Johnson Grass Control

Arle, H. Fred, Everson, E. H. 09 1900 (has links)
No description available.
305

CHEMICAL COMPOSITION AND DIGESTIBILITY OF LEHMANN LOVEGRASS (ERAGROSTIS LEHMANNIANA) IN RESPONSE TO GRAZING AND CLIPPING INTENSITIES.

Osman, Mohamoud Abdullahi. January 1982 (has links)
No description available.
306

Relative effects of landscape and local habitat characteristics on grassland songbird abundance and occurrence in southwestern Manitoba

Lockhart, Jessica 14 September 2016 (has links)
I investigated the relative effects of grassland cover and fragmentation per se, and the relative influence of landscape and local habitat characteristics on grasslands songbirds in the moist mixed-grass prairies of Manitoba. In 2013, 361 avian point counts were conducted across 47, 2.4-km radii landscapes in the southwest part of the province. I used an information-theoretic approach to rank and select models describing effects of landscape and local-scale habitat variables on grassland songbird abundance and occurrence. Overall, my results indicate that grassland amount, fragmentation and quality, and matrix composition had relatively small and variable effects on grassland songbird abundance and occurrence, but that abundance of obligate species when pooled showed a strong negative response to grassland fragmentation. While fragmentation through edge effects may contribute to obligate species declines, my results suggest that these factors alone are unlikely to explain ongoing declines of grassland birds in southwestern Manitoba. / October 2016
307

Analýza tenisové taktiky elitních hráčů na travnatém povrchu / Tactic analysis of elite tennis players at grass court

Šodek, Pavel January 2016 (has links)
The name of work: Tactic analysis of elite tennis players at grass court The aim: The aim of this work was to find what is the conception of tennis tactic by elite players on grass surface by quantitative analysis of tactical ways of selected players during tournament Wimbledon 2014. Method: The analysis was based on indirect monitoring of video records from Wimbledon 2014. It was used a quantitative investigation using line method in folios. Own analysis was made through a descriptive method. Results: It underlines the tactical methods of elite players on grass surface. Key words: tactic, tennis, grass, elite players
308

"I See You Face to Face": The Poet-Reader Relationship in Walt Whitman's "Crossing Brooklyn Ferry"

Case, Christopher David January 2004 (has links)
Thesis advisor: Robert Kern / In this paper, I argue that Walt Whitman alters his poetic program from his first to second edition of Leaves of Grass. By intensifying the emphasis on individuality and personality, Whitman overcomes the limitations of his vastness by allowing for intimate contact with a future reader. I continue to argue that the poem "Crossing Brooklyn Ferry" exemplifies the emphasis on individuality and personal union. Instead of assuming a relationship with his reader, Whitman sets for himself the goal of making this relationship possible. / Thesis (BA) — Boston College, 2004. / Submitted to: Boston College. College of Arts and Sciences. / Discipline: English. / Discipline: College Honors Program.
309

Padrões demográficos de perfilhamento e produção de forragem em pastos de capim-mombaça submetidos a regimes de lotação intermitente. / Demographic patterns of tillering and herbage production in mombaça grass pastures submited to regimes of intermittent stocking.

Uebele, Marina Castro 04 June 2002 (has links)
A otimização de sistemas de pastejo não pode ser concebida simplesmente como a maximização da quantidade de forragem produzida ou ingerida pelos animais, sendo necessário considerar parâmetros que condicionam e determinam a persistência e a produtividade da pastagem. Nesse ponto, assegurar a capacidade de reposição de perfilhos assume importância fundamental. Dentro desse contexto, o objetivo deste experimento foi avaliar os efeitos de diferentes combinações entre intensidade e frequência de desfolha sobre a dinâmica, a densidade populacional de perfilhos e o acúmulo de forragem em pastos de capim-Mombaça pastejados por bovinos, visando determinar estratégias de manejo do pastejo que permitam obter alta produtividade e utilização de forragem, mantendo a estrutura do pasto dentro de limites aceitáveis de uso e garantindo, assim, a sua perenização. O experimento foi realizado na Universidade Federal de São Carlos, Araras, SP, entre 8 de janeiro de 2001 e 23 de fevereiro de 2002. Os tratamentos corresponderam a combinações entre duas intensidades (30 e 50 cm de resíduo) e duas freqüências de desfolha (pastejo iniciado com 95% e 100% de interceptação de luz do dossel - IL) e foram alocados às unidades experimentais conforme um delineamento de blocos completos casualizados e arranjo fatorial 2 x 2, com 4 repetições. O intervalo médio entre pastejos variou de 23 a 36 dias para os tratamentos de 95% e 100% IL, respectivamente, durante o período de primavera/verão. Durante o inverno, esses valores variaram de 95 a 186 dias. A altura do pasto em pré-pastejo foi um parâmetro confiável para ser utilizado como guia de manejo do pastejo baseado em condições de interceptação luminosa, uma vez que apresentou comportamento consistente e uniforme ao longo do período experimental. De forma geral, não houve diferenças entre as taxas de aparecimento e morte de perfilhos entre tratamentos. No entanto, taxas altas de mortalidade foram acompanhadas por taxas altas de aparecimento de perfilhos, com os maiores valores observados durante o período de primavera/verão relativamente a outono/inverno. Alta freqüência (95% IL) e/ou alta intensidade de desfolha (30 cm de resíduo) condicionaram a ocorrência de maiores taxas de mortalidade, propiciando uma maior renovação de perfilhos e, assim, um perfil mais jovem da população quando comparados aos tratamentos de desfolha menos freqüente (100% IL). Não houve diferença em densidade populacional de perfilhos (média de 380 perfilhos m -2 ), indicando que as diferenças em produção de forragem (18.230 a 27.220 kg MS ha -1 ) devem ter sido consequência de diferenças em produção por perfilho, com perfilhos jovens sendo mais eficientes no processo produtivo do que perfilhos mais velhos, fato que justificou a maior produção do tratamento 30/95 (27.220 kg MS ha -1 ). A densidade populacional de perfilhos variou com a época do ano, com os maiores valores registrados na época de verão, seguidos por aqueles do outono e primavera (400, 384 e 344 perfilhos m -2 , respectivamente). Os maiores valores de massa de forragem (8.100 kg MS ha -1 ) e altura em pré-pastejo (116 cm) ocorreram para os tratamentos que tiveram o pastejo iniciado com 100% IL comparativamente aos de 95% (5.400 kg MS ha -1 e 89,5 cm, respectivamente), pois estes permitiram um período de crescimento mais longo e, provavelmente, maior acúmulo de hastes e material morto, o que dificultou a manutenção do resíduo de 30 cm. Houve efeito de época do ano para todas as variáveis estudadas, indicando comportamento fortemente estacional do crescimento do capim-Mombaça. A partir dos resultados obtidos e considerando-se a importância da manutenção de uma alta taxa de renovação de perfilhos para otimização da produção e utilização de forragem, o pastejo deve ser iniciado quando os pastos atingem 90 cm de altura (95% IL) e interrompido quando rebaixado a 30 cm. / The optimization of grazing systems cannot be conceived simply as a maximization of the amount of produced herbage or dry matter consumed by grazing animals. It is necessary to take into account factors that condition and determine the persistence and productivity of pastures in order to ensure the ability of plants to replace dead tillers and maintain pasture stability. Against this background, the present experiment aimed at evaluating the effects of four combinations of grazing frequency and intensity on tiller dynamics/population density and herbage production of grazed Mombaça grass pastures to provide a firm basis for planning grazing management strategies that allow for high herbage productivity and utilization, preserving pasture structure within acceptable limits of use and ensuring its persistence. The experiment was carried out at Universidade Federal de São Carlos, Araras, SP, from 8 January 2001 until 23 February 2002. Treatments comprised combinations between two grazing intensities (post-grazing heights of 30 and 50 cm) and two grazing frequencies (grazing initiated at 95% and 100% canopy light interception - LI), and were assigned to experimental units (2000 m 2 paddocks) according to a complete randomized block design, following a 2x2 factorial arrangement, with 4 replications. The average grazing interval varied from 23 to 36 days for the 95 and 100% LI treatments, respectively, throughout the spring/summer period. During the winter, these intervals ranged from 95 to 186 days. Pre-grazing pasture height was a reliable grazing management guide based on canopy light interception, since it presented a homogeneous and consistent behavior during the entire experiment. There was no difference in tiller appearance and death rates among treatments. High tiller death rates, however, were accompanied by high tiller appearance rates, with higher values recorded during spring/summer in relation to autumn/winter. High grazing frequency (95% LI) and/or intensity (30 cm post-grazing height) resulted in the highest tiller death rates, causing a high tiller turnover that generated a younger profile in tiller population density compared to the low frequency treatments (100% LI). There was no difference in tiller population density among treatments (average of 380 tillers m -2 ), indicating that differences in herbage production (18,230 to 27,220 kg DM ha -1 ) must have been consequence of differences in production per tiller, with younger tillers being more productive than older ones, which was the main reason for the highest forage yield of the 30/95 treatment (27,220 kg DM ha -1 ). Tiller population density varied with time of the year, with higher values recorded during summer in relation to autumn and spring (400, 384 e 344 tillers m -2, respectively). The highest values for pre-grazing herbage mass (8,100 kg DM ha -1 ) and pre-grazing pasture height (116 cm) were recorded for the 100% LI treatments compared to 95% LI (5,400 kg DM ha -1 and 89.5 cm, respectively), since they resulted in longer grazing intervals than the 95% LI treatments. Accumulation of stem and dead material was certainly the main reason for the difference in herbage mass, and made it difficult for grazing pastures down to the target 30 cm post-grazing height. There was a season effect on all responses studied, indicating a very seasonal growth behavior of Mombaça grass pastures. Based on the results and baring in mind the importance of a high tiller turnover for optimizing herbage production and utilization, grazing must be initiated at 90 cm pre-grazing height (95% LI) and stopped at 30 cm post-grazing height.
310

Visual verses: Edward Weston's photographs for Walt Whitman's Leaves of Grass, 1941-1942

Weiss, Francine January 2012 (has links)
Thesis (Ph.D.)--Boston University / PLEASE NOTE: Boston University Libraries did not receive an Authorization To Manage form for this thesis or dissertation. It is therefore not openly accessible, though it may be available by request. If you are the author or principal advisor of this work and would like to request open access for it, please contact us at open-help@bu.edu. Thank you. / This dissertation examines the photographs created by Edward Weston during his travels through the United States in 1941 and intended for a luxury reprint of Walt Whitman's Leaves ofGrass published by the Limited Editions Club in 1942. By contrasting the hundreds of photographs Weston made now residing in archives and collections with the forty-nine images ultimately selected and arranged by the Club's director, George Macy, I argue that Weston's larger, more complex and diverse version of America more closely resembled Whitman's text than his publisher's limited selection. Moreover, this under-examined body of work promotes a new understanding of Weston's late oeuvre; inspired by cross-country travel, Whitman's poetry, and other artists, Weston tackled new subject matter, experimented with different styles, and synthesized artistic and documentary modes in his photographs. Chapter I introduces the commission, the role of Weston's wife Charis Wilson in the project, the timely choice in 1941 of pairing Whitman and Weston, both of whom challenged boundaries of their respective media, and the outcome of the book's design. Chapter 2 turns to an analysis of the sequence of the first ten images as representative of Macy's caption-driven approach to the book, which generally discouraged the probing of close relationships among images. The chapter concludes with an analysis of the images themselves paired with close readings of select poems in order to establish the parallels in sensibility of the two artists. Chapters 3 through 5 broaden the discussion by including Weston's unpublished images from the 1941 trip. Focusing on Weston's portraits, Chapter 3 discusses Weston's diverse sitters-African and Native Americans and womensometimes selected while researching ethnography. Chapter 4 focuses on landscapesindustrial, urban, desert, and rural-in which he engaged with popular American imagery and created art and documentary images. Chapter 5 analyzes Weston's photographs of plantation ruins and cemeteries in Louisiana, and folk art and customs for which he recorded examples of American ethnography. Through examination of these images, a new picture of Weston emerges as not only a modernist art photographer, but also a photographer with deep interests in American people, landscape, and culture. / 2031-01-01

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