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Improving Hay Quality By Ammoniation, K J. Moore, V L. Lechtenberg, K S. Hendrix, J M. Hertel Jun 2026

Improving Hay Quality By Ammoniation, K J. Moore, V L. Lechtenberg, K S. Hendrix, J M. Hertel

IGC Proceedings (1977-2023)

Experiments were conducted to determine the effect of hay ammoniation on hay consumption and weight gain by steers when the hay was fed unsupplemented and supplemented with energy and protein. Mature orchardgrass (Dacrylis glomerata L.) hay was baled in early June 1979 and treated with anhydrous ammonia at 30 g/kg of hay. Seven weeks after treatment the hay was uncovered and allowed to aerate for 3 days. It was then fed to weanling steer calves weighing approximately 225 kg each. Similar hay baled from the same field but not ammoniated was fed to separate groups of steers. Both the treated …


Effect Of Solvent Treatments On Intake And Digestibility Of Corn Stover, D M. Schaefer, M R. Ladisch, C H. Noller, V L. Lechtenberg Jun 2026

Effect Of Solvent Treatments On Intake And Digestibility Of Corn Stover, D M. Schaefer, M R. Ladisch, C H. Noller, V L. Lechtenberg

IGC Proceedings (1977-2023)

Treatment of crop residues with low levels of sodium hydroxide has been shown to improve organic-matter digestibility and animal performance. One objective of these experiments was to evaluate the effects of three treatments -water, sodium hydrox­ide, and chelating metal cellulose-swelling solution-on solubilization of cell-wall components in corn (Zea m£rys) stover. The two latter treatments were balanced for level of sodium hydroxide application, which was .3 .2 % of stover dry matter. The second objective was to determine the effects of these treatments on in-vitro and in-vivo digestibility as well as on consumption of corn stover. Twelve growing ram lambs were …


Soil Health Analysis (Lesson 2), Mara Johnson, Madhav P. Nepal, Jiyul Chang Jun 2026

Soil Health Analysis (Lesson 2), Mara Johnson, Madhav P. Nepal, Jiyul Chang

iLEARN Teaching Resources

In this lesson, students will build on the previous lesson (reading and analyzing the Three Sisters chapter from Braiding Sweetgrass) by experimenting on soil in their schoolyard. Students will collect soil samples from multiple locations around their school grounds and evaluate soil texture, structure, infiltration, color, organic matter, and pH. Students Through field observations and laboratory analysis, students examine how soil characteristics influence plant growth and ecosystem health. Students connect modern soil science with Indigenous agricultural knowledge, particularly the Three Sisters planting system described in Braiding Sweetgrass by Robin Wall Kimmerer. By exploring how healthy soil supports sustainable agriculture, …


Exploring Regenerative Vegetable Systems On The Central Coast Of California, Una S. O'Connell Jun 2026

Exploring Regenerative Vegetable Systems On The Central Coast Of California, Una S. O'Connell

Master's Theses

As climate change and current agricultural practices place pressure on the long term sustainability and resilience of food production systems, there is growing interest in whether existing agricultural systems can adapt to maintain productivity while improving environmental outcomes.

This study evaluated the effects of regenerative versus standard organic vegetable production systems on yield, insect communities, and weed suppression across three field trials conducted on California's Central Coast. In addition, I collected baseline soil health data for all trials. Trials 1 and 2 were carried out at the Cal Poly San Luis Obispo Organic Farm using cabbage and broccoli as cash …


Effect Of Leaf Harvesting Frequency On Cassava Leaf Production And Tuber Yield Of Binulak, Lakan 1 (Upl Cv-2), And Sultan 6 (Nsic 2003 Cv-25), Fides Marciana Z. Tambalo, Rosa Buena A. Capuno, Hiyasmin Rose L. Benzon, Jayson F. Garcia, Lizette Sahar N. Arcillas, Rona Joy C. Tud Jun 2026

Effect Of Leaf Harvesting Frequency On Cassava Leaf Production And Tuber Yield Of Binulak, Lakan 1 (Upl Cv-2), And Sultan 6 (Nsic 2003 Cv-25), Fides Marciana Z. Tambalo, Rosa Buena A. Capuno, Hiyasmin Rose L. Benzon, Jayson F. Garcia, Lizette Sahar N. Arcillas, Rona Joy C. Tud

The Philippine Agricultural Scientist

Cassava (Manihot esculenta Crantz) is a vital staple crop in many developing countries, valued for its adaptability and dual-purpose use of roots and leaves. This study investigated the effects of leaf harvesting frequency on the leaf and tuber yields of 3 locally grown cassava varieties: Binulak, Lakan 1, and Sultan 6. The experiment followed a split plot in a Randomized Complete Block Design with 4 treatments varying in leaf harvesting frequency and initiation. Cassava leaves were harvested at 4, 6, 8, or 10 mo after planting (MAP), and tubers were harvested at 10 MAP. Results indicated that leaf yield …


Assessing Nitrogen Leaching Risk In Organic Vegetable Production, Megan Widle Jun 2026

Assessing Nitrogen Leaching Risk In Organic Vegetable Production, Megan Widle

Master's Theses

Nitrogen (N) leaching is the primary driver of groundwater contamination in agricultural regions. On California’s Central Coast, Agricultural Order 4.0 regulates this risk by constraining field-level N balances (N applied minus N removed). However, the assumption that unrecovered N is lost via leaching may not hold in organic and regenerative systems that promote soil organic matter accumulation. This study evaluated whether measured N leaching aligns with estimates derived from partial N budgets in organic systems, and whether management practices (intercrops, cover crops, and reduced tillage) can mitigate leaching risk. Four field trials were conducted to investigate N dynamics in organic …


Part I: Drip Tape Irrigation For Cut Flowers, Alex Rodriguez, Melanie Stock, James Frisby, Burdette Barker Jun 2026

Part I: Drip Tape Irrigation For Cut Flowers, Alex Rodriguez, Melanie Stock, James Frisby, Burdette Barker

All Current Publications

Drip irrigation can be the most efficient method for delivering water and has the added benefit of keeping moisture off foliage and blooms of cut flowers. This fact sheet is the first in a series of irrigation fact sheets for cut flowers. It provides a step-by-step guide to the initial selection and installation of a surface drip tape irrigation system. Descriptions of and considerations for common components, setup, management, and repair are discussed. While this content may apply to other horticultural and garden plants, this fact sheet was developed for cut flower crops and growers. We recommend USU Extension resources …


Fate Of Nitrogen Applied To Grassland In Animal Wastes, M Sherwood May 2026

Fate Of Nitrogen Applied To Grassland In Animal Wastes, M Sherwood

IGC Proceedings (1977-2023)

The experiment was designed to determine the effects of land spreading of animal manures on the nutrient content of surface runoff water and infiltrating soil water. This report deals only with nitrogen (N) and attempts to quantify the losses through runoff, leaching, and volatilization of ammonia (NH3) as well as N uptake in the grass over a 3-year period. Experimental plots sited on grassland, on two soil types (a moderately drained loam and an impermeable gley), were equipped to collect surface runoff water. Ceramic probes were installed in each plot at 15-, 30-, 60-, and 100-cm depths to extract in­filtrating …


Nitrogen Losses From Urine-Affected Areas Of A New Zealand Pasture, Under Contrasting Seasonal Conditions, P R. Ball, D R. Keeney May 2026

Nitrogen Losses From Urine-Affected Areas Of A New Zealand Pasture, Under Contrasting Seasonal Conditions, P R. Ball, D R. Keeney

IGC Proceedings (1977-2023)

Grazing ruminants aggregate large quantities of forage nitrogen (N) into urine patches. Pasture plots treated with urine N were studied to assess its fate under contrasting seasonal conditions: cool-moist (representing winter-spring); warm-moist (late spring-early summer), and warm-dry (late summer-autumn). A permanent ryegrass (Lolium perenne L.)-white clover (Trifolium repens L.) sward on free-draining alluvial soil was studied. 'freatments were replicated in randomized blocks. Urine N was applied at 30 or 60 g N/m2• Relevant measurements were then continued until treatment differences disappeared. Apparent N balances for urine treatments were compiled. Fixation by white clover was always greatly reduced in …


Effects Of Water Stress On Herbage Quality, J R. Wilson May 2026

Effects Of Water Stress On Herbage Quality, J R. Wilson

IGC Proceedings (1977-2023)

Uncertainty exists about whether drought is detrimental to the nutritive quality of herbage. This paper tries to resolve this uncertainty by examining the influence of soil moisture on some herbage-quality characteristics. Unpublished data from my own work and review of published literature are presented. Field plots of three tropical grasses, green panic (Panicum maximum var. trichoglume), buffelgrass (Cenchrus ciliaris), and speargrass (Heteropogon contortus), were subjected to perioqs of controlled drought, and herbage from these plots was compared with that from well-watered plots. Leaf and stem dry-matter ?igestibility of water-stressed herbage was either similar to or higher than that of unstressed …


Consumption Rates And Desert Grassland Herbivores, R D. Pieper May 2026

Consumption Rates And Desert Grassland Herbivores, R D. Pieper

IGC Proceedings (1977-2023)

Studies were conducted on a desert grassland range in southern New Mexico for 3 years to determine relative consumption rates of the main herbivores utilizing these range areas. Consumption of some groups (cattle, pronghorn antelope, and rabbits) was determined from direct estimates of intake/individual, and density was determined from censusing procedures or known stock rates. Consumption by other groups (birds, rodents, and invertebrates) was determined from census information relating to age structure of the population and metabolic rate. Consumption by all herbivores averaged less than 5 % of the above-ground net primary productivity for the 3 years of the study. …


Performance Of A Subtropical Legume-Grass Pasture Under Different Grazing Management Systems, G E. Maraschin, S C. Mella, G S. Irulegui, J Riboldi May 2026

Performance Of A Subtropical Legume-Grass Pasture Under Different Grazing Management Systems, G E. Maraschin, S C. Mella, G S. Irulegui, J Riboldi

IGC Proceedings (1977-2023)

Agronomic evaluation of the dynamics of tropical legume-based pastures is relevant in assessing the response of their com­ponents within systems of grazing management. The response of tropical legume-grass mixtures to periods of rest and grazing pressure and the combinations that result in meaningful legume content in the mixture need to be known. A central composite design was used to study the performance of a Desmodium intortum (Mill.) U rb. and Paspalum gttenoarum Arech. pasture mixture to 14, 28, 42, 56, and 70daysofrestcombinedwith 2.0%, 3.5%, 5.0%, 6.5%, and 8.0% BW(i.e., kg dry matter (DM) on offer/day/100 kg body weight) as grazing …


Legume Establishment In Grass-Dominant Swards: Concept And History In Kentucky, T H. Taylor, W C. Templeton Jr May 2026

Legume Establishment In Grass-Dominant Swards: Concept And History In Kentucky, T H. Taylor, W C. Templeton Jr

IGC Proceedings (1977-2023)

Grassland farming has been practiced for 2 centuries in central Kentucky and for shorter periods in other parts of the state. Savannas and tallgrass prairies were severely grazed by domestic animals and row-cropped by early settlers, destroying most of the indigenous plant species. By the early part of the 19th century, beef cattle were being produced on bluegrass (Poa pratensis L.) pastures and driven on foot to east-coast markets. During the first century of settlement, farmers learned to top-seed legumes into grass sods, and in the course of the last hundred years development of grassland technology for establishing legumes …


Seed And Seedling Dynamics Of Annual Medic Pastures In South Australia, E D. Carter May 2026

Seed And Seedling Dynamics Of Annual Medic Pastures In South Australia, E D. Carter

IGC Proceedings (1977-2023)

Annual species of Medicago (i.e., medics) are the key to successful cereal-pasture rotations in the integrated crop-livestock farming systems on the neutral to alkaline soils of southern Australia. However, many medic stands have deteriorated in recent years. This deterioration has prompted research on the effects of grazing sheep on the seed-seedling dynamics of annual medic­based pastures in the Mediterranean environment of South Australia, aiming to quantify the impact of medic seed reserves in or on the soil upon pasture establishment and productivty.

Animal-house experiments involving the feeding of purepod and pod-chaff diets to sheep and a field experiment have been …


Physiology Of Growth Of A Grazed Sward, E L. Leafe, A J. Parsons May 2026

Physiology Of Growth Of A Grazed Sward, E L. Leafe, A J. Parsons

IGC Proceedings (1977-2023)

To improve our understanding of grassland utilization under grazing, the physiology of a grazed sward was investigated. An enclosure method, infrared gas analysis, and radiocarbon were used to measure sward and single-leaf photosynthesis and assimilate utilization. Intake by sheep was also measured. Expanding and recently expanded leaves had high rates of net photosynthesis but leaf sheaths, whose projected area in a "hard" grazed sward equaled that of the lamina, had low efficiency and contributed little to canopy photosynthesis. But because high leaf efficiency did not compensate for the small leaf area, canopy photosynthesis decreased markedly as grazing intensity increased. Twice …


Grassland Development In The Southern Highlands Of Peru, E J. Stevens, P Villalta May 2026

Grassland Development In The Southern Highlands Of Peru, E J. Stevens, P Villalta

IGC Proceedings (1977-2023)

This paper describes grassland development in Peru. Vegetation of the high alpine region of Peru, which occupies some 4 million ha, is dominated by native grasses normally producing less than 2,000 kg/ha dry matter annually. On land with ade­quate soil moisture, pastures based on perennial ryegrass (Lolium perenne L.) and white clover (Trifolium repens L.) were established successfully, but on drier sites alfalfa proved superior, producing over 12,000 kg/ha/yr in some trials. Alfalfa and clovers were also successfully introduced into improved native pastures by mechanical direct seeding and by hand sowing. With direct seeding, dry-matter production increased from about …


Pasture Evaluation In The Desertic Zone Of Venezuela For The Development Of Goat Production, A Gallardo, A Leone May 2026

Pasture Evaluation In The Desertic Zone Of Venezuela For The Development Of Goat Production, A Gallardo, A Leone

IGC Proceedings (1977-2023)

The desertic zone of Venezuela is an area of approximately 4.1 million ha that represents 4.8 % of the total national territory, on which there are two million goats. Goats represent the main, if not the only, income source for 60,000 rural families. According to UNESCO (1973), the desertic zone of the country comprises two vegetation types, evergreen scrub and deciduous scrub. In each of these zones the plant species consumed by goats were collected and, for those plant parts consumed by the animals, chemically analyzed to determine nutritive value. Forage plants from other tropical countries were also in­troduced and …


Evaluation Of Biological Components In Decision-Making In Forage Allocation, J E. Skiles, G M. Van Dyne May 2026

Evaluation Of Biological Components In Decision-Making In Forage Allocation, J E. Skiles, G M. Van Dyne

IGC Proceedings (1977-2023)

Forage allocation to mixtures of large herbivores is accomplished by minimizing the difference between the available herbage and the required forage for animals on rangeland. Availability is determined in part by the plant's physiological tolerance to grazing or its allowable-use factor and the animal preference for that plant, measured in part by the proper-use factor. The mix of large herbivores on the rangeland must also be considered. The grazing requirements for animals are dependent on animal preference for plant species and on the total forage intake rates. This paper presents an analysis of these concepts and published information. The concept …


Effect Of Converting Chaparral To Grassland On Soil Fertility In A Mediterranean-Type Climate, M B. Jones, R L. Koenigs, C E. Vaughn, A H. Murphy May 2026

Effect Of Converting Chaparral To Grassland On Soil Fertility In A Mediterranean-Type Climate, M B. Jones, R L. Koenigs, C E. Vaughn, A H. Murphy

IGC Proceedings (1977-2023)

In the region of Mediterranean-type climate in California, brush is converted to grassland to reduce fire hazards, increase feed for herbivores, and increase water yields. There is little information on how this change of cover type affects soil fertility over a long period. Research was initiated to measure the long-term effect of converting brush to grass on the availability of nutrients in the soil. In 1956 chaparral growing on Los Gatos soil (fine-loamy, mixed mesic family of typic argixerolls) was crushed, burned, and seeded to grasses and clovers, and half the area was fenced to exclude herbivores. Sprouting brush either …


Resource Allocation For Animal-Grassland Systems, G W. Thomas May 2026

Resource Allocation For Animal-Grassland Systems, G W. Thomas

IGC Proceedings (1977-2023)

The production of animal products from grasslands is dependent upon an adequate resource base-particularly the availabil­ity ofland, water, and energy. In addition, range and pasture production systems must be designed to adjust to climatic varia­tions and to minimize adverse environmental impacts. Several new developments will have a significant impact on the future allocation of resources for animal agriculture: (1) in­creased competition for land and water, which is leading to transfers from agricultural to nonagricultural uses; (2) increasing costs and decreasing availability of "cultural energy" (particularly fossil fuels); (3) more pressure to divert grains and feed con­centrates from animals to direct …


Multiple Use Of Grassland Resources (Grasslands To Provide Natural Resource Conservation And A Quality Environment For Mankind), P J. Edwards May 2026

Multiple Use Of Grassland Resources (Grasslands To Provide Natural Resource Conservation And A Quality Environment For Mankind), P J. Edwards

IGC Proceedings (1977-2023)

The grasslands of the world ( and communities closely akin to them, such as shrub and savanna types) provide not only a very effective mantle for protection of the soil, but also the main source of feed for herbivores. They also cater to many other needs of mankind. Increasing population results in competition between types of grassland use for specific sites. Sound planning is necessary to resolve this conflict in the way most beneficial to mankind. In order to plan logically it is necessary to make an inventory of the resources, to consider the various uses to which grasslands can …


Nitrogen Relationships In Grassland Ecosystems, A Lazenby May 2026

Nitrogen Relationships In Grassland Ecosystems, A Lazenby

IGC Proceedings (1977-2023)

Some recent findings affecting nitrogen (N) cycling in grassland ecosystems are discussed, and an indication is given of major problems requiring research and development. The importance of modern techniques is stressed to enable further quantification of the pathways and processes of the nutrient in grassland; such data are needed both to improve understanding and to enable more efficient use of N in practice. A brief description of the N in soil organic matter is followed by an account of symbiotic N fixation by legumes, including estimated levels and rates of fixation and factors affecting the process. Data are presented on …


Contribution Of Forages To Worldwide Food Production: Now And In The Future, E F. Henzell May 2026

Contribution Of Forages To Worldwide Food Production: Now And In The Future, E F. Henzell

IGC Proceedings (1977-2023)

Herbivorous livestock provided during the 1970s an estimated minimum 7%-17% of the total dietary protein in Asia and Africa compared with about 30 % in Latin America and just over 30 % in the developed countries. Cattle accounted for approx­imately 70% of the world's domestic animals (calculated in units weighted for size), buffaloes for 10%, and sheep and goats for 11 % . About 69 % of these animal units were in the developing countries, but productivity was higher in the developed coun­tries. Forages, defined broadly to include all edible plant materials except grains and concentrates, provided more than 90% …


Potential Productivity Of Temperate And Tropical Grassland Systems, G O. Mott May 2026

Potential Productivity Of Temperate And Tropical Grassland Systems, G O. Mott

IGC Proceedings (1977-2023)

Grasses of temperate regions of the world belong primarily to the subfamily Festucoideae, whereas tropical regions are populated by tribes of the Panicoideae subfamily. Temperate grasses have a C3 biochemical pathway of photosynthesis in con­trast to tropical grasses, which have a C4 photosynthetic mechan-ism. Both tropical and temperate legumes are C3 plants. Com­patible mixtures of legumes and grasses have long been successful in many temperate regions, but combining C4 grasses and C3 legumes as mixtures in the tropics has been only moderately successful. Maximum net primary productions of temperate and tropical grasslands are in the order of 25 and 80 …


Use Of Genetic Resources For Improvement Of Forage Species, J R. Harlan May 2026

Use Of Genetic Resources For Improvement Of Forage Species, J R. Harlan

IGC Proceedings (1977-2023)

The use of genetic resources of forage species poses some special problems because of the number of species involved, the in­adequacy of our knowledge about them, the fact that they are often used in combination and should be evaluated in terms of livestock product, and so on. Collections should be as comprehensive as possible at the outset of improvement programs; other­wise, there may be much use of inferior material and much waste of time and effort. Most of the forage species in use come from (1) Europe (excluding Mediterranean zones), (2) Mediterranean Basin and Near East, (3) African savannas (mostly …


Forage Quality: Assessing The Plant-Animal Complex, D J. Minson May 2026

Forage Quality: Assessing The Plant-Animal Complex, D J. Minson

IGC Proceedings (1977-2023)

At the VI International Grassland Congress held at Pennsylvania State College in 1952, the late Dr. C.P. McMeekan re­viewed the many problems associated with the plant-animal complex. Great stress was placed on the need to measure forage in­take accurately as a prerequisite to an under-standing of the plant-animal complex. Progress in the development of more accurate :methods of estimating the forage intake of grazing animals is reviewed, in­cluding the introduction of different methods of administering chromic oxide, the esophageal fistula for obtaining samples of selectively grazed material, the in-vitro technique for estimating the digestibility of the forage eaten, and the …


Competitive, Adaptive, And Evolutionary Process In Grassland Ecosystems, B D. Patil May 2026

Competitive, Adaptive, And Evolutionary Process In Grassland Ecosystems, B D. Patil

IGC Proceedings (1977-2023)

In the tropics, grasslands or grazing lands are found where the forest vegetation climax has been subjected to fire, grazing, felling, or other disturbances. Grazing lands in the tropics form various ecosystems under the major climatic types. Delineation of such ecosystems is possible through remnants of the climax vegetation of undisturbed or least-disturbed areas. Several subecosystems exist as seral stages under each ecosystem, the floristic composition of which is a reflection of the edaphic and soil­moisture-fertility conditions. Biological production in terms of energy for grazing animals varies among these ecosystems and subecosystems. Reconstruction of the adaptable competitive flora with woody …


Growth And Development Of Two Echinochloa Millet Species In A Warm Temperate Climate, D K. Muldoon May 2026

Growth And Development Of Two Echinochloa Millet Species In A Warm Temperate Climate, D K. Muldoon

IGC Proceedings (1977-2023)

Most summer forage crops fall into either the sorghum or the millet species group. Included in the millet group are two species, Echinochloa utilis and Echinochloa frumentacea, commonly known as Japanese barnyard millet and Indian barnyard millet, respectively. These species have a negligible HCN potential and higher nutritive value than Sorghum species. However, they generally flower early, yield less than forage sorghum , and lack vigor in regrowth. In this study the pattern of growth and development of two Echinochloa millets was examined as part of a larger program of improving the production of these forage species. E. utilis …


Test Adaptation And Evaluation Trials Of Forage Plants In Major Ecological Regions Of Ethiopia And Kenya, K M. Ibrahim, A Orodho May 2026

Test Adaptation And Evaluation Trials Of Forage Plants In Major Ecological Regions Of Ethiopia And Kenya, K M. Ibrahim, A Orodho

IGC Proceedings (1977-2023)

Kenyan and Ethiopian natural grazing Ian.cl. support more than 20% of the cattle population of the African continent. Many of the natural pastures of these countries are severely overgrazed, as unfavorable grazing conditions prevail for over half the year. Objectives of adaptation trials were to evaluate and identify introduced or indigenous forage and fodder species or ecotypes having genetic potential for high production of digestible dry matter for direct pasture and range improvement and for future use in breeding programs. Over 4,000 indigenous and 3,000 introduced ecotypes were evaluated for 24 vegetative characters in six ecological regions between 1971 and …


Neutral Detergent Fiber And Protein Levels In Diploid And Tetraploid Ryegrass Forage, L R. Nelson, F M. Rouquette Jr May 2026

Neutral Detergent Fiber And Protein Levels In Diploid And Tetraploid Ryegrass Forage, L R. Nelson, F M. Rouquette Jr

IGC Proceedings (1977-2023)

Nutritive value of 18 ryegrass (Lolium multifloriumLam.) cultivars was studied at Overton, Te1

0.42-mm screen. Plots were harvested four times during each of the first 2 years and five times in the third year. In 1977-1978 and 1978-1979, NDF and protein analyses were run on samples from 2 replications. All forage samples were analyzed for pro­tein via the micro-Kjeldahl technique. Percentages of NDF were obtained via Van Soest extraction procedures. A seasonal increase in neutral detergent fiber (NDF) content and a decrease in protein percentage was observed. Differences in NDF were observed among cultivars and were most apparent during …