Life Sciences Commons^™

Ec96-780 Equipment Wheel Spacing For Ridge-Till And No-Till Row Crops, Robert D. Grisso, Paul J. Jasa, Alice J. Jones, Todd A. Peterson

University of Nebraska-Lincoln Extension: Historical Materials

Use of ridge-till and no-till systems has increased dramatically since the early 1980s when ridge-planting equipment and conservation tillage cultivators became readily available. The ridge-till system involves the establishment and annual re-forming of permanent, single-row ridges into which crops are planted year after year. To obtain maximum productivity with the ridge-plant system (and many believe with no-till systems), all wheel traffic should be confined to interrows. Wheel traffic on ridges can alter the ridge profile and condition of crop residue. Ridge deformation or excessive tire sinkage can affect subsequent planter performance, crop emergence and the overall productivity of both ridge-till …

G96-1296 Gear Up And Throttle Down -- Saving Fuel, Robert Grisso, David P. Shelton, Kenneth Von Bargen

University of Nebraska-Lincoln Extension: Historical Materials

"Gear Up and Throttle Down" is a fuel-saving practice suitable for light drawbar loads (less than 65 percent of full power) when reduced PTO speed is not a problem.

For the most efficient operation, a tractor's engine should be operated near its rated capacity. However, there are many field operations (such as light tillage, planting, cultivating, and hay raking) that do not require full tractor power. This is especially true when older implements, which were sized for a smaller tractor, are used with higher horsepower tractors. Also, many operations should be performed at a fixed field speed.

For these lighter …

G96-1312 Autumn Freeze Probabilities, Steven J. Meyer, Allen L. Dutcher

University of Nebraska-Lincoln Extension: Historical Materials

Autumn freeze probabilities based on 47 years of data are examined for 48 locations in Nebraska.

The potential of an early autumn freeze is of great concern to farmers, gardeners, and other plant growers. A climatological analysis of autumn freeze events across Nebraska can provide a measure of the risk involved with planting different hybrids, varieties and cultivars.

Nf96-288 Using Life Insurance In Farm And Ranch Estate Planning, Paul H. Gessaman

University of Nebraska-Lincoln Extension: Historical Materials

This NebFact contains information on using life insurance in estate planning.

Nf96-310 Costs Of Harvesting And Hauling Corn Stalks In Large Round Bales, H. Douglas Jose, Lance L. Brown

University of Nebraska-Lincoln Extension: Historical Materials

This NebFact calculates the costs of harvesting corn stalks for either livestock fodder or industrial uses.

G96-1285 Dairy Health Management For Optimum Production And Reproductive Performance, Duane N. Rice, Rick J. Grant, Larry L. Larson

University of Nebraska-Lincoln Extension: Historical Materials

Maintaining a healthy herd is a constant challenge to today's dairy producer. This NebGuide suggests ways to increase and maintain the quality of your dairy herd. Maintaining a healthy herd is a constant challenge to today's dairy producer. Each year an average of 20 to 25 percent of dairy cows are culled due to poor reproductive performance or other health problems. Many factors influence the health and performance of a dairy herd. These include the entire scope of management factors from "on farm" activity to the associated business and financial interactions. All of these are controllable but require knowledge and …

Ec96-824 Dairy Economics In Nebraska: An Analysis Of Costs And Returns And Comparisons With Other States, H. Douglas Jose, Richard J. Grant

University of Nebraska-Lincoln Extension: Historical Materials

Dairy Economics in Nebraska

The dairy sector is undergoing major structural changes and economic adjustments. The industry is also becoming more market oriented as government price supports decline. Increased competitiveness has kept milk prices relatively stable, but increased grain and other input costs in 1995-96 have put increased pressure on profit margins which were already narrow.

This publication is a compilation of data related to the current economics of dairy farming. The objective is to provide data to help dairy farmers make adjustments in their operations, such as expanding their herds, and to provide basic data for operators setting up …

Neotropical Bird Migration During The Ice Ages: Orientation And Ecology, Timothy C. Williams , '64, T. Webb Iii

Biology Faculty Works

Reconstruction of breeding habitat of North American Neotropical migrants 18,000 years ago and 9,000 years ago indicated major shifts in both location and composition of plant communities relative to present conditions. Increased vegetation in xeric areas may have compensated, at least in part, for the reduction in breeding habitat due to glaciation. Autumnal flights of Neotropical passerine migrants flying on constant headings from North America to Central and South America were simulated under present wind conditions and for winds during periods of glaciation at 18,000 and 9,000 years ago. The 155 degrees average headings currently observed for Atlantic migrants were …

Allometry Of Litter Mass In Bats: Maternal Size, Wing Morphology, And Phylogeny, Virginia Hayssen, T. H. Kunz

Biological Sciences: Faculty Publications

We examine how litter mass in bats varies with respect to wing loading, an important aerodynamic aspect of flight. From geometric proportions, litter mass should scale to wing loading by an exponent of three. Conversely, analysis of aerodynamic consequences of carrying extra mass suggests that an exponent significantly less than three would be selectively advantageous. Our results show that Megachiroptera and Microchiroptera differ in the relationship between litter mass and wing loading. Litter mass in megachiropterans scales as expected by geometric proportions, whereas litter mass in microchiropterans, as a group, and for individual families, scales as expected if aerodynamic consequences …

Evaluation Of The Crop Growth Component Of The Root Zone Water Quality Model For Corn In Ohio, Sue E. Nokes, Feliks M. Landa, Jon D. Hanson

Biosystems and Agricultural Engineering Faculty Publications

The Root Zone Water Quality Model (RZWQM) is a computer model developed to simulate water, chemical, and biological processes in the root zone of agricultural management systems. As of this writing RZWQM is in the beta-testing phase of development. This article reports on a parameterization and evaluation study performed in Ohio on field corn for the crop growth component of RZWQM. The generic crop growth model in RZWQM had not previously been parameterized or tested on field corn. This article reports the results of such a study. One year of data was used to calibrate RZWQM, and two additional years …

Comparison Of Daily Water Table Depth Prediction By Four Simulation Models, Eric D. Desmond, Andrew D. Ward, Norman R. Fausey, Stephen R. Workman

Biosystems and Agricultural Engineering Faculty Publications

The Agricultural Drainage And Pesticide Transport (ADAPT) model was compared to the water management simulation models DRAINMOD, SWATREN, and PREFLO. SWATREN and PREFLO are one-dimensional finite-difference models while ADAPT and DRAINMOD are one-dimensional mass balance models. ADAPT, an extension of the computer model GLEAMS, also provides chemical transport information. All four models were tested against field data from Aurora, North Carolina. Observed water table depth data were collected during 1973 through 1977 from a water table management field experiment with three subsurface drain spacing treatments of 7.5, 15, and 30 m.

Both the standard error of estimate and the average …

Performance Of Vegetative Filter Strips With Varying Pollutant Source And Filter Strip Lengths, Puneet Srivastava, Dwayne R. Edwards, Tommy C. Daniel, Philip A. Moore Jr., Thomas A. Costello

Biosystems and Agricultural Engineering Faculty Publications

Vegetative filter strips (VFS) can reduce runoff losses of pollutants such as nitrogen (N) and phosphorus (P) from land areas treated with fertilizers. While VFS effectiveness is considered to depend on lengths of pollutant source and VFS areas, there is little experimental evidence of this dependence, particularly when the pollutant source is manure-treated pasture. This study assessed the effects of pollutant source area (fescue pasture treated with poultry litter) length and VFS (fescue pasture) length on VFS removal of nitrate N (NO₃-N), ammonia N (NH₃-N), total Kjeldahl N (TKN), ortho-P (PO₄-P), total P (TP), …

Book Review - This Fragile Land. A Natural History Of The Nebraska Sandhills, Neil P. Bernstein

Journal of the Iowa Academy of Science: JIAS

Paul Johnsguard presents a highly enjoyable and readable introduction to the natural history of the Nebraska Sandhills in his "kind of love letter to the Nebraska Sandhills and especially to their inhabitants past and present." Johnsguard calls upon 30 years of research and teaching in the region to draw together a series of essays that cover geology, ecology, ethology, and environmental issues while offering his personal perspectives on the past, present and future.

Checklist Of Instructions For Authors

Journal of the Iowa Academy of Science: JIAS

No abstract provided.

Editorial Board & Iowa Academy Of Science Officers And Directors

Journal of the Iowa Academy of Science: JIAS

No abstract provided.

Patterns Of Dilatation Growth In Ficus Pumila And Ficus Sycomorus, Simcha Lev-Yadun

Aliso: A Journal of Systematic and Floristic Botany

Dilatation growth occurs in the secondary phloem rays, in the axial secondary phloem parenchyma, and in the parenchyma of the cortex of Ficus pumila (a Iiana) and Ficus sycomorus (a tree). Dilatation growth in Ficus pumila is mostly the result of meristematic activity, but in Ficus sycomorus it is the result of both meristematic activity and increase in cell size. Dilatation meristem is formed in the rays in various patterns: in the center of the ray, at one or two of the ray's margins, in horizontal or diagonal strips (relative to the axis) in the ray, or in more than …

Baccharis Malibuensis (Asteraceae): A New Species From The Santa Monica Mountains, California, R. Mitchell Beauchamp, James Henrickson

Aliso: A Journal of Systematic and Floristic Botany

Baccharis malibuensis is described from the Malibu Lake region of the Santa Monica Mountains, Los Angeles County, California. It is closely related to Baccharis plummerae subsp. plummerae but differs in having narrow, subentire, typically conduplicate, sparsely villous to mostly glabrous leaves with glands occurring in depressions on the adaxial surface, more cylindrical inflorescences, and a distribution in open chaparral vegetation. The new taxon shares some characteristics with B. plummerae subsp. glabrata of northwestern San Luis Obispo County, e.g., smaller leaves, reduced vestiture, and occurrence in scrub habitat, but the two taxa appear to have developed independently from B. p. subsp. …

Crossroads, Milestones, Amd Landmarks In Insect Development And Evolution: Implications For Systematics, Rob Desalle, Donat Agosti, Michael Whiting, Beatriz Perez-Sweeney, James Remsen, Rick Baker, James Bonacum, Ranhy Bang

Aliso: A Journal of Systematic and Floristic Botany

Our understanding of insect development and evolution has increased greatly due to recent advances in the comparative developmental approach. Modem developmental biology techniques such as in situ hybridization and molecular analysis of developmentally important genes and gene families have greatly facilitated these advances. The role of the comparative developmental approach in insect systematics is explored in this paper and we suggest two important applications of the approach to insect systematics--character dissection and morphologicallandmarking. Exi~ng morphological characters can be dissected into their genetic and molecular components in some cases and this will lead to more and richer character information in systematic …

Studies In Macrosiphonia (Apocynaceae): Generic Recognition Of Telosiphonia, James Henrickson

Aliso: A Journal of Systematic and Floristic Botany

Woodson recognized two subgenera within Macrosiphonia (Apocynaceae: Apocynoideae), a South American subgenus Eumacrosiphonia, and a North American subgenus Telosiphonia each with five species. Both taxa are characterized by low subshrub-shrub, nonviny growth habits, white, long-tubed, vespertine corollas of a type associated with moth pollination. Their distinctive anther and style-tip characteristics show each is related to a group of genera around Mandevilla and Mesechites. The two subgenera, however, differ strongly from each other in inflorescence, style-head structure, and pollen size indicating that they are not sister taxa and that Macrosiphonia as currently recognized is polyphyletic. Thus the subgenus Telosiphonia …

Integrating Cellular And Molecular Approchaes Into Studies Of Development And Evolution: The Issue Of Morphological Homology, Andrés Collazo, Scott E. Fraser

Aliso: A Journal of Systematic and Floristic Botany

Understanding the development and evolution of complex morphological characters requires broad, multidisciplinary approaches. By combining biological imaging, phylogenetic analyses, embryological manipulations and additional modem molecular techniques (e.g., whole mount in situ hybridization), we can address fundamental questions, such as the determination of homology. Many of the novel structures that evolved in vertebrates and distinguish them from their ancestors (such as jaws and the mechanosensory lateral line) are derived embryonically from two migratory ectodermal tissues, neural crest and/or various epidermal placodes. In particular, time-lapse cinematography of fluorescently labeled cells in living Xenopus and fish embryos has proved a powerful technique, revealing …

Cattle Industry Compensation Act Research Advisory Committee Progress Report 1996, Cattle Industry Compensation Act Research Advisory Committee

Animal production and livestock published reports

The Cattle Industry Compensation Fund was established under the Cattle Industry Compensation Act 1965. An Advisory Committee, established by the Hon. Minister for Primary Industry makes recommendations for funding on a project basis. The Advisory Committee published progress reports in 1984 and 1989. This report covers the period 1990 to 1995.

Achievements In Wool, Agriculture Western Australia

Animal production and livestock published reports

The Wool Strategy Group, which I initiated in 1993, works with Agriculture Western Australia's Wool Program to set the strategic directions for its activities. Chaired by Mr Philip Gardiner, it has members whose experience include fashion, marketing, financial markets, wool production, selling, as well as strong industry linkages. This document outlines the activities that the Group and the Program have been undertaking over the past 12 months.

The Chairman of the IWTO has recently suggested that Australian production in the coming years will be insufficient or not of the right specifications to supply market demands.

In order to assist Western …

Improving Dairy Farm Performance, Ruth Dilley

Journal of the Department of Agriculture, Western Australia, Series 4

Western Austraian sairy farmers produce more milk per cow and per farm than their eastern Sttates counterparts and the milk is also of higher quality. But there is always room for improvement and as grain prices rise it is crucial that maximum benefit is derived from the cheapest feed source - the pasture.With this in mind Ruth Dilley looks at the Dairy Farm Performance Program - a comprihensive farm database developed by Agriculture Western Australia.

Abandon The Paddock : A Valid Method Of Rehabilitation?, Max Abensperg-Traun

Journal of the Department of Agriculture, Western Australia, Series 4

The scale of the revegetayion needed to combat land and habitat degradation can only be achieved over a long period of time. An alternative to revegitation is to abandon parts oof the farm for passive regeneration. Max Abensperg-Traun, and his colleagues from CSIRO Division of Wildlife and Ecology, report on some outomes from such a strategy.

Positive Price Outlook For Wheat : Implications For Wa Agriculture, Alan Haagensen, Ian Wilkinson

Journal of the Department of Agriculture, Western Australia, Series 4

After a 40 year period over which wheat prices have dropped by an average of 2.7 per cent annually in real terms, fundamental changes in wheat supply and demand look set to reverse this trend. It is possible that real prices could increase by as much as 4 per cent anually in the medium term.

Alan Haagensen and Ian Wilkinson look at the forecasts for wheat prices and outline the forces that will influence world supply and demands for wheat.

Options For Pest Management In Pastures, Phil Michael, Mike Grimm, Mike Hyder, Peter Doyle

Journal of the Department of Agriculture, Western Australia, Series 4

Redlegged eath mit, blue oat ite, lucern flea and aphids damage pastures across southern Australia, and it has been estimated that they cause annual losses to the Australian wool industry alone of over $200 million.

Redlegged earth mite is without doubt the most serious of the four pests. Peter DoPhil Michael, Mike Grimm, Mike Hyder and Peter Doyle discuss intergrated management options to control these pests.

Top-Down Cascade From A Bitrophic Predator In An Old-Field Community, Matthew D. Moran, Thomas P. Rooney, L. E. Hurd

Biological Sciences Faculty Publications

We tested the hypothesis that a bitrophic (third and fourth level) arthropod predator can exert a cascading, top-down influence on other arthropods and plants in an early successional old field. First-stadium mantids, Tenodera sinensis, were added to replicated open-field plots in numbers corresponding to naturally occurring egg hatch density and allowed to remain for ≈ 2 mo. Sticky-trap dispersal barriers around both control and mantid-addition plots allowed us to monitor emigration of arthropods continuously during the experiment. Biomass of herbivores, carnivores, and plants, and abundances of arthropod taxa within plots were determined at the beginning, middle, and end of …

Higher-Order Categories In Brunei Dusun Ethnobotany: The Folk-Classification Of Rainforest Plants, Jay H. Bernstein

Publications and Research

No abstract provided.

Cover - Table Of Contents

Journal of the Iowa Academy of Science: JIAS

No abstract provided.

Bald Eagles Wintering Along The Des Moines River, Iowa, Neil Sabine

Journal of the Iowa Academy of Science: JIAS

Distribution, habitat use, and foraging behavior of Bald Eagles (Haliaeetus leucocephalus) wintering in southeast Iowa were studied in January - March 1990 and November 1990 - March 1991. Eagles were seen from November through March with the highest numbers in January and February. Adults had shorter winter residence times than immatures and they appeared to be less active during the day. Eagles concentrated their foraging efforts along certain river segments where they fed exclusively on fish. Timber harvesting along the river reduced eagle use and is considered to be the most serious threat to sustaining eagle use of the area. …