Weed Science Commons^™

Management Of Arid Pastures, Cyrus M. Mckell, Don D. Dwyer

IGC Proceedings (1977-2023)

Arid pasture, natural grazing land, or rangeland are synonymous terms used to describe the extensive areas of open, non-cultivated arid lands over which domestic livestock and wildlife roam in search of feed. These lands are characteristically low in productivity and if managed, the level of management is extensive and based on ecological principles. The term rangeland originated in the United States of America and is gradually gaining usage in other countries to differentiate between intensively managed pastures of humid and sub-humid regions, and the open steppes, deserts, shrub­lands and dry non-commercial forested lands which, in addition to grazing, provide non­consumptive …

New Objectives And Modern Methods Of Forage Grass Breeding In The German Democratic Republic, Heinrich Baudis

IGC Proceedings (1977-2023)

The objectives of forage grass breeding in the GDR are derived from the social development processes which, in socialist agriculture, find their expression in further intensification, concentration and spezialization of plant and animal production. New aspects which have been recognized only recently, for example, positive response to intensification measures, suitability for industrialized production me­thods, increased yield stability and improved quality in addition to a higher yielding poten­tial, have the decisive say in the breeding tar­gets. The most important traits and properties from the breeder's point of view are dealt with in detail. Explanations on practical breeding work and on some …

Possibilities Of Dry Matter Production From Forage Plants Under Different Climatic Conditions, Th Alberda

IGC Proceedings (1977-2023)

On the basis of the gross photosynthesis of closed green grass swards the net potential dry herbage production of permanent pastures is calculated for the climatic and soil conditions for the so-called broad soil regions and summa­rized per continent. The values thus obtained form the upper level of dry herbage production to be reached on the prevailing permanent pas­ture area. Subsequently the minimum level of dry herb­age production is calculated, based on data on the production of marketed secondary prod­ucts as meat and milk. Since not all these secondary products are marketed and since not all the herbage produced is …

The Gene Pool And Its Use In Breeding Grassland Plants, Anna Novoselova

IGC Proceedings (1977-2023)

1. The gene pool of grassland plants is of great diversity and localized in certain centres of origin where the carriers of germ plasma are concentrated for the most important bio­logical characters and properties of a great variability of species.

2. New intensive varieties for mowing and grazing have been bred by advanced breeding methods and by taking advantage of the gene pool of the most important plant species throughout the world.

3. Wild-growing species were found to have great prospects for opening up soils of poor productivity by mowing and grazing use. They constitute a great reserve of genetic …

The Environment And Population Differences In Anjan Grass (Cenchrus Ciliaris) In Western India, S C. Pandeya

IGC Proceedings (1977-2023)

Cenchrus ciliaris (anjan or buffel grass) is a gregarious fodder species with high nutritive value. The species is an inhabitant of drier sandy areas throughout Africa, Canary Island, Madagascar and eastwards to India, where it mostly occurs in western parts of the country, constituting the States of Gujarat, Rajasthan, Hayana and the adjoining portions of Punjab, U ttar Pradesh and Madhya Pradesh ( called here in as Western India). In Western India, Cen­chrus ciliaris (Cc) variously dominates the nat­urally occurring grazing lands exhibiting great morphological variations with respect to habit. and spike characters. The ecoclimate of Western India is arid …

Review Of 50 Years Grassland Farming And Trends Of Development In The Further Intensification Of Forage Production In The German Democratic Republic, Eberhard Wojahn

IGC Proceedings (1977-2023)

This our XIII International Grassland Congress is being held at the invitation of the Govern­ment of the German Democratic Republic following the decision of the XII International Grassland Congress in Moscow in 1974 that this Congress shall be held as a jubilee event here in Leipzig. It is the Jubilee Congress reminding us of the First International Grass­land Congress which was held 50 years ago, during the last days of May, 1927, in this time-honoured University town and centre of world trade. Because of that jubilee character this XIII International Grassland Congress is of very special importance.

Influence Of Feeding On Health And Productivity Of Ruminants, Alexander Sommer

IGC Proceedings (1977-2023)

As to the utilization of plant matter not suited for direct consumption by man, ruminants are of outstanding importance. This fact is related with the function of their specific stom­ach system. The paper discusses the microbial protein synthesis from NPN compounds. When 50 per cent of digestible crude protein required by fattening cattle were replaced, daily live weight gains of 997 g were reached; beef quality was not affected. Similarly favourable results were obtained with dairy cows when replacing by NPN compounds 50 to 100 per cent of extracted meals. Further on, the problem of crude-fibre diges­tion in connection with …

Assessing Integrated Pest Management Protocols For The Invasive Aquatic Weed Giant Salvinia (Salvinia Molesta), Samantha Lee Prinsloo

LSU Doctoral Dissertations

Giant salvinia (Salvinia molesta) is free-floating aquatic fern that originates from South America. Through human introduction, giant salvinia has escaped its native range and is listed as an invasive species across multiple continents causing negative socio-economic and environmental impacts. This research aimed to expand our understanding of integrated pest management for controlling giant salvinia by combining chemical and biological control. The objectives were to assess the effects of rainfastness, carrier volume, and growth stage on herbicide efficacy, assess augmented biological control and optimal weevil release densities, assess weevil populations in the field, determine herbicide and surfactant toxicity to …

Impact On Energy Budgets In Grassland Production And Conservation Of Possible Production Of Energy From Biomass Crops, R J. Wilkins

IGC Proceedings (1977-2023)

There is commonly a conflict between output/unit of area of land and output/unit of support-energy (SE) input. The possibil­ity of using a proportion of the total land area for biomass energy production suggests an approach for calculating grassland out­put/ha unconfounded with differences in SE input. Output can be calculated for an area of land that is devoted to grassland and biomass energy crops in proportions that result in a net demand for SE of zero. Outputs of utilized metabolizable energy (UME) are related to inputs of SE for (1) grazed grass with high application of nitrogen (N) fertilizer and (2) …

Efficiency Of Dairying Under Contrasting Feeding And Management Systems In North America, Israel, Europe, And New Zealand, J.D. J. Scott

IGC Proceedings (1977-2023)

Four different systems of feeding and managing dairy cattle are seen in major milk-producing countries. These are (1) feeding purchased roughages and concentrates to zero-grazed, intensively penned cows; (2) home growing of roughages and most con­centrates for zero-grazed animals; (3) feeding concentrates with conserved pasture and other roughages in winter and reduced concentrates to grazed cattle in spring-summer; and (4) feeding cattle on grazed pasture and conserved pasture throughout the year. The following data on the four systems were obtained from examples in southern California, Wisconsin, England/Wales, and New Zealand. Average fat-corrected milk (FCM)/cow is approximately 7,140, 5,300, 4,670, and …

Potential Contribution Of White Clover To The Economics And Support-Energy Inputs Of Grass-Based Beef-Production Systems, T A. Stewart, R E. Haycock, A S. Laidlaw

IGC Proceedings (1977-2023)

Biological output, gross margins, and efficiency of support-energy usage in an 18-month beef-production system on grass-white clover swards receiving either 50 kg N/ha stocked at 3.3 head/ha (low N) or 300 kg N/ha stocked 4.5 head/ha (high N) were compared. To date, two production cycles (1977-1979 and 1978-1980) at two sites have been completed. Mean live-weight and carcass gains/ha were, respectively, 17.5% and 14% higher from the high-N than from the low-N system. Gross margin/head was higher from the high-N system in the first production cycle but not in the second. In the low-N system as com· pared with the …

An Evaluation Of The Black Walnut- Tall Fescue Pasture-Management System, H E. Garrett, W B. Kurtz

IGC Proceedings (1977-2023)

The economic and biological feasibility. of a black walnut-livestock-grazing multicropping-management regime bas been evaluated for comparison with a similar livestock-management regime conducted in the open. Pure tall fescue plots were established under open and black walnut-shade conditions. Forage yields on a dry-weight basis were estimated for a 3-year period. A concurrent grazing trial was co􀀌ducted on similar sites using 1.2-ha plots. Black walnut seedlings were planted within the plots on a 3 x 12-m spacing and protected from grazing animals by electric fencing. The economic analyses of the alternate grazing systems were based on their respective present net worth and …

Economics Of Renovating Mountain Hay Meadows, J J. Jacobs

IGC Proceedings (1977-2023)

There are approximately 0.5 million hectares (ha) of irrigated native grass hay in the mountain and intermountain regions of California, Oregon, Idaho, Utah, Nevada, Montana, Wyoming, and Colorado. Often these lands are not producing at their full physical or economic potential. The objectives of this study were to identify alternative improvement procedures to increase hay production and to determine the economic feasibility of those alternatives. The principal means of identifying alternative mountain hay-meadow improvement practices and their costs was personal in­terviews with ranchers. The ranchers interviewed were owners and/or operators of mountain ranches in Wyoming who were us­ing or had …

Pasture Demonstration Program For Beef: Economic Considerations, P R. Hasbargen, R H. Craven, N P. Martin

IGC Proceedings (1977-2023)

This study made an economic evaluation of several alternative pasture improvement programs on beef farms in northern Minnesota. Three questions were addressed relative to several pasture improvement systems. These were (1) Will it pay? (2) Is there a cheaper way? and (3) Is there a more profitable system for a particular farm resource situation? Partial budgeting and computerized linear programming techniques were used to analyze pasture cost and return data obtained from several ranches in northern Minnesota. Study results show that rented pastures, when available, provided the cheapest source of additional summer feed, and that legume pastures provide cheaper sources …

Pennsylvania's Alfalfa Growers Program: Four Years Of Success, J E. Baylor, L E. Lanyon, W K. Waters

IGC Proceedings (1977-2023)

Alfalfa (Medicago sativa L.) is the most important perennial forage legume grown in Pennsylvania. However, yields currently reported by farmers are considerably below what might be expected when all production inputs are utilized. Therefore, a pro­gram was developed (1) to measure how much alfalfa hay, protein, and energy can be pro􀀗uced on 1 ha of Pennsylvania land under nonirrigated conditions, (2) to determine the mineral content and uptake by high-yielding alfalfa crops, and (3) to obtain more realistic on-farm estimates of alfalfa production costs. To achieve the program goals, hay production for each harvest from 2.02-ha farm fields was …

Estimation Of Digestibility Of Legume Forages By Means Of Morphological Parameters, W Kuhbauch

IGC Proceedings (1977-2023)

Forage quality is normally evaluated by time-consuming and costly laboratory analyses. It appears promising to use mor­phological parameters to evaluate forage quality in alfalfa and red clover. During progressive growth of white clover, red clover, and alfalfa, the leaf and stem portion was separated to determine the fiber fraction according to the Van Soest method and to

estimate digestibility by the procedure of Tilley and Terry. Stem : leaf ratio and stand height as a measure of stem length were used as morphological parameters. Leaves of the three legumes vary only slightly in concentration of cell-wall material and in digestibility …

Income, Costs, And Profits Associated With Feeding Selected Forages To Dairy Cows, D D. Dornfeld, D A. Rohweder, W T. Howard

IGC Proceedings (1977-2023)

Over the last i0 years, dairy-farm enterprises have g:ro-wn in size, with an apparent increase in use of improved scientific feeding and management techniques. There in growing emphasis on automated feeding and milking and on management stcategies in an attempt to reduce labor needs and allow more cows/worker. The average herd size in the sample population was 76.8 cows. There was difficulty finding herds over 100 and under 40 head. It appears that the trend toward increasing growth will continue, as much as sufficient capital, management ability, and debt service capacity eJi:ist to permit the growth to occur. Forage management …

Economic Analysis Of The Impact Of Management Decisions On Production And Use Of Silage For A Dairy Enterprise, A J. Corrall, H D. St. C Neal, I M. Wilkinson

IGC Proceedings (1977-2023)

The aim of this work was to examine the influence of variations in grass management and methods of ensiling on the economics of milk production for autumn-calving cows. A simulation model was developed to combine knowledge of plant and animal responses and their interactions in order to calculate the effects of management options on economic balances. Input data were compiled for herbage production from cut­ting strategies that gave herbage at four digestibilities, at two levels of applied nitrogen, and in three climates. Experimental evidence was also collated to construct matrices of loss of dry matter and changes in digestibility and …

Role And Effectiveness Of U.S. Universities In Training Professionals For Work In International Agriculture, D F. Fienup

IGC Proceedings (1977-2023)

Problems of hunger, malnutrition, and world food security became a major world concern in the 1970s. Two U.S. presiden­tial reports have emphasized the seriousness of the situation and the need to expand food production and distribution, par­ticularly in the less-developed countries (LDCs) where hunger is most severe. The LDCs need to strengthen agricultural teaching, research, and extension in order to develop and disseminate the ap­propriate technology farmers need to increase food production. The most limiting factor is often the lack of trained scientists to provide local leadership and expertise. Here U.S. and other developed-country universities are needed to train LDC …

Innovations In Academic Curricula For International Education, D D. Dwyer

IGC Proceedings (1977-2023)

A major contribution of U.S. AID to developing countries has been to support the education of host-country nationals. This form of assistance has not been without its problems, as both AID and the universities themselves have been less than totally ef­fective in meeting the challenge of providing an education that best serves the student and the home country. In most developing countries, the B.S. degree serves as an adequate scientific foundation for staffing agricultural programs. This is not to argue against higher levels of education but to state that faster progress could be made by spreading the educational efforts among …