Physical Sciences and Mathematics Commons^™

Pre-Tertiary Subcrop Rocks In The Nebraska Panhandle, Conservation Annd Survey Division

Conservation and Survey Division

No abstract provided.

Inferred Areal Extent Of The Oligocene (White River Group) Chadron Basal Sand, Conservation And Survey Division

Conservation and Survey Division

No abstract provided.

Configuration Of The Base Of The Principal Aquifer, Conservation And Survey Division

Conservation and Survey Division

No abstract provided.

Soil Additives And Alternative Crops For Drought Defense In The Intermountain West, Tina M. Sullivan

All Graduate Theses and Dissertations, Fall 2023 to Present

The Western U.S. looks for water optimization and conservation as agriculture is the largest water diverter, and resources are pressured by urban growth, winter snowpack instability, and drought persistence. Agricultural producers have several potential options to optimize water use with different investments associated with them. Options with varying levels of risks and known management practices include alternative crops, soil wetting agents, and crop biologicals.

An alternative crop that grew incredibly fast in popularity was industrial hemp (Cannabis sativa) despite limited agronomic knowledge for best management practices. Field trials occurred (2020-2022) near Logan, UT to test a total of …

Autumn Grass Growth- The Effect Of Rest Interval, R Neilan, E G. O'Riordan, G Keane

IGC Proceedings (1993-2023)

The effect of closing dates (Experiment 1: August 1, August 14 and September 18) and grass regrowth interval (Experiment 2) on herbage yield in the autumn/winter and in the following spring were investigated on a previously grazed Lolium perenne sward. In Experiment 1, similar yields were obtained for the August 1 and August 14 closing. Yields decreased and the proportion of dead material increased from 0.19 to 0.61 between mid-October and late- December. In Experiment 2, dry matter yield increased linearly (P < 0.05) with rest interval up to 7 wks in swards closed in September. There was no significant yield advantage for rest intervals greater than 5-6 wks. It is concluded that accumulated autumn and spring yields showed increased DM production with the shorter regrowth intervals.

Improving Pasture Composition Increases Wool Returns In Eucalypt Woodlands, T J. Hall, R G. Silcock, J J. Sevil, J R. Van Der Meulen

IGC Proceedings (1993-2023)

A sheep grazing experiment in red earth Eucalypt country on semiarid pastures dominated by either Gayndah buffel grass (Cenchrus ciliaris) or wiregrass (Aristida jerichoensis) quantified liveweight, wool production and quality, and financial returns. Wethers were grazed at 0.32 and 0.6 ha/sheep. In year 1 there was no significant effect of either stocking rate or pasture type on liveweight or wool growth rate. Vegetable fault was greater in the fleeces from the wiregrass. The sheep grazing buffel grew better than those on wiregrass when stocking rates were doubled in year 2, while pasture yields remained high. The …

Responses Of Artemisia Herba-Alba Asso. And Its Associated Species To Grazing Frequency (Midelt, Morocco), M Mejjati Alami, O Berkat, C Bensalem

IGC Proceedings (1993-2023)

The objective of this study (conducted in 1994) was to assess the effects of season and grazing frequency (control, continuous, intermittent during 2 days per week) on vegetation attributes, and animal feeding behavior. Mean standing crop, for which Artemisia herba alba contributed 72%, attained 533 for the control while it was maintained at 394 and 322 Kg DM/ha, for the continuous and the intermittent grazing, respectively. Mean productivity of Artemisia herba alba varied according to treatment and had values of 5.3, 3.0 and 2.5 Kg DM/ha/day, under the ungrazed control, the continuous and the intermittent grazing regimes, respectively. Percent utilization …

Grazing Management Of An Italian Ryegrass Sward With Dairy Sheep In The Mediterranean Environment, M Sitzia, P P. Roggero, N Fois, G Molle

IGC Proceedings (1993-2023)

A grazing experiment was conducted in North-West Sardinia with the aim of testing the sward height as a mean to set up an efficient spring management of Italian ryegrass (Lolium multiflorum Lam.). Three fields were continuously grazed during spring 1992 by three groups of 12 dairy Sarda ewes, at three different sward heights (SH): 30 - 60 - 90 mm. The target sward height was obtained by continuously adjusting the field sizes. The results showed that the different grazing managements influenced the above ground biomass production and partitioning of the Italian ryegrass and the animal performances. During the vegetative …

Estimation Of Herbage Intake Of High Producing Milking Cows Under Intensive Grazing With A Supplementary Feeding Method In Northern Japan, K Ohiai, K Sudo, T Ikeda, T Honma

IGC Proceedings (1993-2023)

The objective of this study was to estimate the herbage intake and to assess a supplementary feeding method for high producing milk cows under intensive grazing. Eight high producing milking cows were grazed rotationally on perennial ryegrass (Lolium perenne L) dominant mixed pasture and on meadow fescue (Festuca elatior L) dominant mixed pasture, changing rotation period and grazing area ccording to seasonal pasture growth rate. Pasture intakes were estimated to be about 2% of body weight by TDN requirements estimation of animals. A supplementary feeding method is examined to be proper for high producing milking cows under …

Palatability Of Grasses And Grazing On Hungarian Grassland, Z Barcsak, I Kertesz, L Szeman

IGC Proceedings (1993-2023)

Grasslands provide the most basic and cheapest forage diet for cattle. The palatability studies were carried out on pure and mixed swards sown in 1990 on the GATE experimental farm. The studies involved the following 12 species: Lolium perenne, Trifolium repens, Festuca arundinacea, Festuca rubra, Poa pratensis, Festuca pratensis, Bromus inermis, Phalaris arundinacea, Lotus corniculatus, Agropyron crystatum, Dactylis glomerata and a mixed sward. During the study the morning and afternoon grazings were investigated with the involvement of 60 Limousin cattle. The following observations were made: 1. On the basis of our ethological observations regarding the bite rates the animals found …

Selective Sheep Grazing In An Heterogeneous Wheatgrass Dominated Pasture Related To Stocking Rate, G L. Siffredi, M A. Brizuela, M S. Cid, C Cangiano

IGC Proceedings (1993-2023)

It has been hypothesized that patch and community selection are driven by forage quality and/or quantity. We assess the relationship between vegetation characteristics and community and patch selection by sheep under continuous grazing at different stocking rates in an heterogeneous pasture. Our results suggest that when communities strongly differed in nutritive value sheep recurrently select the higher quality community in spite of its low biomass. However, sheep do not completely exclude the poorer quality community, generating a patchy vegetation pattern.

Grazing Management Of Elephant-Grass For Milk Production, F Deresz, L L. Matos

IGC Proceedings (1993-2023)

The objectives of these experiments were to study the effects of three resting periods (RP) of elephant-grass pasture on milk production and composition of Holstein-Zebu cows. These trials were carried out during two consecutive rainy seasons (December to May) using 24 cows in each year. They were randomly assigned by blocks according to milk yield and live weight (LW) to four treatments: 30- day RP with no concentrate (30N), 30-day RP with concentrate (30C), 36 and 45-day RP with C (36C and 45C) in the first year. In the second year the treatments were: 30C, 30N, 36N and 45N. Concentrate …

Comparison Of Yield, Forage Quality And Persistence Of 11 Grasses Grown With Irrigation In A Semi-Arid Climate, D E. Glover, G A. Kielly, R H. Cohen, P G. Jefferson

IGC Proceedings (1993-2023)

Nutritive quality of many grass species used for forage in the Northern Great Plains of Canada and the United States is not well documented, especially at different maturity stages. This study compared agronomic and forage quality characteristics of eleven grasses common to Saskatchewan. Botanical separation and quality analysis was undertaken at three growth stages. Meadow Brome (Bromus riparius), Russian Wildrye (Psathyrostachys juceus) and Altai Wildrye (Elymus angustus) were shown to have high leaf to stem ratios which corresponded with high protein levels. Separations showed persistence of Reed Canarygrass (Phalaris arudinaceus), Creeping Foxtail …

The Effect Of Grazing On Leaf Development In Eight Grass Species, H A. Lardner, S.B M. Wright, R H. Cohen

IGC Proceedings (1993-2023)

Grazing by herbivores affects grass species both morphologically and physiologically. A grazing study was conducted on an irrigated pasture near Outlook, Saskatchewan, Canada during the summers of 1991 and 1992 to determine morphological development of regrowth of reed canarygrass (Phalaris arundinacea L.), slender wheatgrass (Elymus trachycaulus (Link) Gould ex Shinners subsp. trachycaulus), intermediate wheatgrass (Thinopyrum intermedium (Host) Barkw. & D.R. Dewey subsp. intermedium), orchardgrass (Dactylis glomerata L.), meadow bromegrass (Bromus beibersteinii Roem. & Schult.), smooth bromegrass (Bromus inermis Leyss.), tall fescue (Festuca arundinacea (Schreb.) Wimm.) and timothy (Phleum pratense L.) in order to …

The Effect Of Slurry And Dirty Water Application To Swards On Grazing Behaviour In Dairy Cows, S Danby, J A. Laws, P D. Penning, B F. Pain, E Owen

IGC Proceedings (1993-2023)

In preference tests using pairs of turves in boxes (treated and control), dairy cows were more averse to surface spread than shallow injected slurry and more averse to slurry than dirty water. Effects of slurry persisted for up to 6 weeks, with fewer bites and less herbage removed from treated swards compared to control swards. Aversion to slurry may be decreased by injection. Effects of dirty water persisted for only 14 days.

Applications Of Height-Based Grazing Management In Mixed Swards, A Singh, J E. Johnston, E A. Clark

IGC Proceedings (1993-2023)

Grazing efficiency and livestock performance were compared on swards rotationally grazed down to either 50 or 100 mm for three years. With a fixed entry height of 200-250 mm, standing swards of mixed grasses and white clover (Trifolium repens L.) were stratified into 50 mm vertical layers both pre- and post-grazing. Through four or five cycles of grazing each year for three years, a fixed entry height range stabilized total standing herbage at 3250 to 3690 kg OM ha-1. Organic matter on-offer above 100 mm was 36, 45, and 43% of total standing herbage in the three years, compared …

Ingestive Behavior Of Fistulated And Intact Sheep Grazing Grass And Legumes Indoors And Outdoors, Y M. Gong, J Hodgson, M G. Lambert

IGC Proceedings (1993-2023)

Components of short-term ingestive behaviour were recorded for fistulated and intact sheep grazing turves in indoor crates, and for esophageal-fistulated sheep grazing swards in situ in outdoor cages. Perennial ryegrass, orchard grass and white clover at vegetative and reproductive growth stages were offered to the sheep. Bite weight, depth, area and volume did not differ between sheep grazing indoors and outdoors, nor between intact and fistulated sheep. Bite rate of fistulated sheep was slower indoors than outdoors (25.3 versus 32.1 bites/min), and intact sheep had a higher biting rate (36.7 versus 25.3 bites/min) than fistulated sheep. Bite weight was over-estimated …

Dairy Production From Pasture In Southern China, P.N P. Matthews, J Hodgson, A.C P. Chu, W L. Jiang, C B. Luo

IGC Proceedings (1993-2023)

This paper covers the development of dairy production systems as part of the UNDP funded Agro-grasslands Systems Development Project in Guizhou Province, China. The basic philosophy for the project was for local adaptation of New Zealand technology for developing dairy production systems based on pastures. The dairy production systems were established and the outputs of the project successfully achieved. Net incomes of smallholder farmers increased from a baseline of RMB $140 to RMB $1740 per annum over a three year period. Based on the experienced gained in setting up these systems local researchers, administrators, extension personnel and smallholders were able …

Trace Mineral Status Of Beef Cattle Grazing Semiarid Rangelands Of North Mexico, J R. Kawas, G T. Armienta, E Olivares, O Torress, J J. Kawas, F Garza

IGC Proceedings (1993-2023)

Trace mineral concentrations of soil, forage and serum of range cattle of the northeast Mexico state of Nuevo Leon were determined in both wet and dry seasons of 1992. For each season, collections were made at twenty-four ranches within eleven counties of three regions. A total of 220 soil, 680 forage and 220 blood samples were collected and analyzed. No differences (P<0.05) between regions were obtained for Zinc (28.0 to 34.9 ppm) or Copper (4.4 to 5.4 ppm). Molybdenum concentrations were greater in the northern (2.1 ppm) than in the central (1.6 ppm) or southern (1.5 ppm) regions. Considering the critical levels in forages for Zinc (30 ppm) and Copper (10 ppm) reported by the National Research Council (1984), Zinc concentrations may be marginally deficient, whereas Copper concentrations were deficient in all three regions, in both seasons, and in grasses and woody species.

Forage-Based Seasonal Dairying In South Louisiana, H A. Deramus, L Labbe, K Ingawa, W A. Atkinson, M J. Simon, J D. Roussel

IGC Proceedings (1993-2023)

The effects on the net profit and total milk production were compared using two levels of grain supplementation and forage-only feeding in a program of seasonal dairying in South Louisiana using management intensive grazing. Treatments were 8 kg grain, 4 kg grain, and 0 grain supplementation. Annual ryegrass (Lolium multiflorium) and clovers (Trifolium incarnatum, and T. Alexandrinum) were grazed intensively with 51 multiparous Jersey and Holstein cows in mid-lactation in 1993-1995. Milk production, milk fat, milk protein, and blood urea nitrogen were measured. Milk and protein models were all highly significant for all classes. Daily milk …

Influence Of Sheep And Goats On The Natural Succession, H D. Matthes, S Demise, M Schubert, H Mohring

IGC Proceedings (1993-2023)

A study was conducted to examine the effect of extensively-grazed pasture on the botanical composition. The trails were carried out in the year 1992 to 1995. For the study different breeds of sheep with the stocking rate of 30 sheep with their lambs / 2.6 ha were used. For the mixed-grazing a ratio of 20 sheep and 10 goats with their lambs / 2.6 ha were used. It is not possible to control all problem species with the help of sheepgrazing only. In contrast to that, it was concluded that goats grazed off all problem species quite effectively. Botanical composition …

Influence Of Different Breeds Of Pigs To The Natural Succession, H D. Matthes, A.C D. Micklich, G Dietl, H Mohring, W Jentsch

IGC Proceedings (1993-2023)

The aim of this study was to find out the effect of pigs on the natural succession. We used 4 different breeds of pigs for our investigations. Because of the grazing behaviour and their rooting activity the total number of plants increased up to 30%. But the vegetation quickly returned to conditions prior to rooting, if the rooting activity fails to happen. Rooting activity of pigs on floodplain soil and following grazing in the next spring after rooting permits seeds of different species of plants to germinate and develop in the plant free areas. These plants often have little chance …

Infograz: A Data Base For Tropical Grazing Systems, K G. Rickert, J Carter, C K. Mcdonald

IGC Proceedings (1993-2023)

INFOGRAZ is a prototype of a comprehensive relational database that describes the management of, and stores information from, grazing experiments in northern Australia associated with the wool, beef, and dairy industries. It provides permanent storage and public access for detailed measurements on climate, soil, plants, and animals, which are a valuable resource for future pasture scientists and computer modellers of grazing systems. Thus it will prevent the detailed observations being lost with the passage of time. Verified data from each experiment are stored in tables which can be distributed on CD-ROM, along with procedures to access the data and use …

Effects Of Two Grazing Conditions On The Reproductive Achievement Of Male Alpaca In The Northern Peru Grasslands, C Pinares, E Malpartida, S Cortez

IGC Proceedings (1993-2023)

Alpaca have recently been introduced to the northern Peru grasslands (Jalca). Effects of two systems of grazing management, co-grazing (with sheep) under fair grassland condition (CGFC) versus exclusive grazing under good grassland condition (EGGC), upon the reproductive achievement was examined from the 6th to the 16th month of age. Each system involved 20 Huacaya animals, managed by individual herders. Availability of herbage preferred by alpaca (HMA) and animal measurements (herbage intake, liveweight, testicle size, penis release from preputial attachments, plasma testosterone) were monitored monthly. Puberty, judged by the penis release from the preputial attachments, was achieved by 7 …

Experiences Of Eight Ohio Beef And Sheep Producers With Year Round Grazing, H M. Bartholomew, S L. Boyles, B Carter, E Vollborn, D Miller, R M. Sulc

IGC Proceedings (1993-2023)

Livestock producers participated in a demonstration project to extend the grazing season and evaluate dormant forage quality and yield. Differences were not detected in yields among forage species but yield differences existed among sites. Yield estimates did not change over time across all forage species but some sites were only able to participate for two months. Producers utilizing fescue beyond November had reductions in herbage mass. Crude protein, available crude protein, acid detergent fiber, and neutral detergent fiber content differed among forage species and sites. Energy and lignin content were similar for all forage species and sites. Sodium and copper …

Forage Production Of Irrigated Lecerne- Grass Mixtures Grazed By Sheep, M L. Enrique, D P. Minon

IGC Proceedings (1993-2023)

The forage production and botanical changes of lucerne cultivars in pure stands and in grass mixtures were studied in a split-plot experiment with irrigation and sheep grazing. The non dormant lucerne cultivars (Medicago sativa) CUF 101, Monarca SPINTA, P 30 and common were the main plots, and tall fescue (Festuca arundinacea), canarygrass (Phalaris aquatica), cocksfoot (Dactylis glomerata), tall wheatgrass (Thynopirum ponticum) and prairie grass (Bromus catharticus) were the subplots. The experiment was grazed 3, 6 and 4 times during 3 years. Total yield was similar for all lucerne …

Oat Grazing: Forage Composition And Supplementation Response, A J. Freddi, M J. Arzadun, A A. Pissani, P Sastre

IGC Proceedings (1993-2023)

Oat forage (Avena sativa), which has low soluble carbohydrates (SC) and high soluble protein (SP) content, can reduce liveweight gain of grazing animals; supplementation with grain and low degradability protein may serve to counteract the effect. A grazing trial was carried out on two soils with different nitrogen (NO3 -) availability, from 16 April 1994 to 6 September 1994. Steers were randomly allocated to 3 treatments: low nitrogen (LN), high nitrogen (HN) and high nitrogen with supplementation (HNS). Forage of LN showed lower SP (p<0.05) during the first month of grazing, and higher SC (p<0.05), than HN during the first two months of the trial. Animal liveweight gain was: 892, 909 and 775 g/an/day for LN, HNS and HN, respectively, with animals in HN of significantly lower liveweight gain (p<0.05). Under the conditions of this trial, animals grazing on oat forage with lower SC and higher SP had lower liveweight gain and responded to supplementation.

Native And Introduced Forage Systems For Cow-Calf Production, S W. Coleman, W A. Phillips, J D. Volesky

IGC Proceedings (1993-2023)

The objectives of this study was to compare a highly productive introduced warm-season perennial grass to native range for cowcalf production over two years. Three systems, 1) native range with pelleted soybean or cottonseed meal as winter protein supplement (NC); 2) native range with wheat pasture (NW); and 3) Plains Bluestem with wheat pasture (PB) were compared. Protein supplements were given twice weekly and cows grazing wheat pasture were allowed 6 hrs to graze. Cows on NW were heavier with higher condition at breeding in the spring of 1994 than those on NC and cows on PB were heavier and …

Rotational Stocking And Soil Nutrient Distribution On Hawaiian Grasslands, B W. Mathews, J P. Tritschler, L E. Sollenberger

IGC Proceedings (1993-2023)

A naturalized kikuyu (Pennisetum clandestinum Hochst. ex Chiov.) grassland was grazed by heifers (Bos taurus) for 2 years to determine the effects of two rotational stocking methods (short vs. long grazing periods) on soil N, P, K, Ca, Mg, and S distribution in paddocks with natural shade. Additionally, kikuyugrass-greenleaf desmodium (Desmodium intortum Urb.) paddocks were used to evaluate soil nutrient distribution in rotationally stocked paddocks (long grazing periods) without shade. In the study with shade, soil N, P, and K distribution did not differ between stocking methods. These nutrients accumulated within 15 m of shade, but did not …

Relationship Between Height And Sward Quality In Rotational Dairy Systems, M R. Mosquera-Losada, A Gonzalez-Rodriguez

IGC Proceedings (1993-2023)

Height is a good guide for management in dairy systems.Intake by dairy cows depends on amount offered and quality of pasture and for this reason a relationship between that offered and pasture quality with height should be studied. The experiment was conducted in NW of Spain with three different stocking rates in dairy systems. A lower quality sward was found in the taller offered pasture as indicated by its higher ADF and lower CP percentages. Total sward ADF (kg x ha-a) was higher in taller offered pasture, which indicated a lower pasture quality, however the total CP was positively related …