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New Names And Combinations In Encelia Frutescens Sensu Lato (Asteraceae: Heliantheae, Curtis Clark

Aliso: A Journal of Systematic and Floristic Botany

No abstract provided.

Plant Systematics: Beginnings And Endings, Billie L. Turner

Aliso: A Journal of Systematic and Floristic Botany

No abstract provided.

An Inventory And Condition Survey Of The Sandstone-Yalgoo-Paynes Find Area, Western Australia, A L. Payne, A M E Van Vreeswyk, K A. Leighton, H J. Pringle, P Hennig

Technical Bulletins

The inventory and condition survey of the Sandstone-Yalgoo-Paynes Find area, undertaken by the Department of Agriculture and Food, Western Australia (DAFWA) between 1992 and 1993, describes and maps the natural resources of the region’s pastoral leasehold land. This survey report provides a baseline record of the existence and condition of the area’s natural resources, to assist with the planning and implementation of land management practices. The report identified and described the condition of soils, landforms, vegetation, habitat, ecosystems, and declared plants and animals. It also assessed the impact of pastoralism and made land management recommendations. The area surveyed covers about …

Currants, A "Berry" Good Addition To Your Garden, Dennis Hinkamp

All Archived Publications

No abstract provided.

Linking People, Purpose, And Place: An Ecological Approach To Agriculture, Heidi Carter, Richard Olson, Charles A. Francis

CARI Extension and Education Materials for Sustainable Agriculture

Linking Ecology and Agriculture

Whole Farm Planning

Soil Quality

Agroforestry

Grazing Systems

Weed and Insect Management

Farmer Groups

Farmland Conversion

Resources and Information Sources

Center For Grassland Studies Newsletter, Winter 1998, Volume 4, No. 1

Center for Grassland Studies: Newsletters

Contents:

Biological Control of Weedy Exotic Thistles and Its Ecological Side Effects in the Sandhills: Observations (Part 1) by Svata Louda, School of Biological Sciences, UNL

Cutting Edge Technology Used for UNL Football Practice Field by Roch Gaussoin, Department of Horticulture, UNL

Early-summer Grazing Effects on Defoliation and Tiller Demography of Prairie Sandreed by Andrew Cullan, Patrick Reece and Walter Schacht, Department of Agronomy, UNL

Bison/Buffalo Information

East Meets West in 1999: SRM/AFGC Joint Meeting by Heidi Carter, Center for Sustainable Agricultural Systems, UNL

Field Trip Graduate Course on Ecology of Grazing Lands

Nebline, January 1998

NEBLINE Newsletter Archive from Nebraska Extension in Lancaster County

Cooperative Extension takes advantage of geographic technology
Wood for your fireplace
Humidity in the home affects plants, too
Using garden catalogs
Houseplant maintenance
An evergreen for all seasons
Honey bees are dying by the millions!
Congratulations!
Boxelder bugs and the cluster fly
Pesticides and child safety
Extension meetings Scheduled
Crop management winter workshops
City purchases manure spreaders
for use in biosolids program
Feeding high quality hay after calving
Prepare calves for feedlots
Acreage development in Lancaster County
Learning about chemicals
Acreage owners workshop
Indulging without bulging
Focus on Food
A safe kitchen
Healthy Eating: Rib Eye Roast (Prime Rib)
Fast, …

Demographic Viability Of Populations Of Silene Regis In Midwestern Prairies: Relationships With Fire Management, Genetic Variation, Geographic Location, Population Size And Isolation, Eric S. Menges, Rebecca W. Dolan

Scholarship and Professional Work - LAS

1. We studied the demographic viability of populations of a long-lived iteroparous prairie perennial, Silene regia, in relation to management regimes, population sizes, geographical region (Ohio and Indiana vs. Missouri and Arkansas), degree of isolation and amount of genetic variation. Demographic data were collected from 16 populations for up to 7 years.

2. This species has high survivorship, slow growth, frequent flowering and episodic seedling recruitment. Matrix projection methods were used to summarize population performance with and without recruitment. Median finite rates of increase by population varied from 0.57 to 1.82 and from 0.44 to 0.99, respectively.

3. Populations with the highest rates …

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Environmental And Botanical Controls On Peatification - A Comparative Study Of Two New Zealand Restiad Bogs Using Py-Gc/Ms, Petrography And Fungal Analysis, Tomasz K. Kuder, Michael A. Kruge, J C. Shearer, S L. Miller

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

This study shows that chemical properties of two restiad species, Empodisma minus and Sporadanthus traversii, may contribute to their success as peat-formers in a climate of the North Island of New Zealand which is not conducive to raised mire development. Unlike Sphagnum, the equivalent northern hemisphere peat-former, restiads possess lignin in their tissues. In addition, the presence of non-lignin polyphenols (including tannins and phenolic acids) in restiads may be an important factor in peat formation due to the allelopathic decay retardation. Patterns of degradation of plant biopolymers have been examined and the pathway of degradation of monocotyledons (loss …

Introduction, Edward L. Schneider, Roy L. Taylor

Aliso: A Journal of Systematic and Floristic Botany

No abstract provided.

Wood Anatomy Of Calyceraceae With Reference To Ecology, Habit, And Systematic Relationships, Sherwin Carlquist, Melanie L. Devore

Aliso: A Journal of Systematic and Floristic Botany

Qualitative and quantitative data are presented for secondary xylem of 14 species of four genera of Calyceraceae; root wood is studied for acaulescent perennials and one annual. The wood anatomy of most species of Calycera has character states identical to those seen in wood of most Asteraceae (including phylads of Asteraceae thought to be basic in that family). Goodeniaceae have two features (tracheids, diffuse parenchyma) more primitive than corresponding conditions in Asteraceae and CaIyceraceae according to traditional criteria. Diversity in wood anatomy within Calyceraceae is explainable in terms of adaptation to particular ecological conditions. Although woods of the family as …

Weather And Management Impact On Crop Yield Variability In Rotations, Charles Yamoah, Gary E. Varvel, Charles Francis, William Waltman

Department of Agronomy and Horticulture: Faculty Publications

Crop rotations are designed to increase productivity and reduce costs. These advantages are contingent upon favorable weather and require appropriate management. Unpredictable weather poses risks to dryland crop production. Information on how weather affects yields in different cropping systems and how farmers could respond with management would help minimize risk and stabilize yield and income. We evaluated the effects of preseason and growing season weather variability on continuous and sequential cropping of corn, sorghum, and soybean in a 12-yr span, and suggest how management decisions could influence cropping system performance.
Models of different levels of sophistication have been developed to …

A Coalescent Approach To Chloroplast Genome Relationships Within And Between Populations Of Pinus Devoniana In Mexico, Jennifer A. Matos

Aliso: A Journal of Systematic and Floristic Botany

Pinus devoniana, a member of the Pinus montezumae complex (Ponderosae) of Mexico and Central America occurs as scattered populations from the western states of Jalisco and Nayarit to Chiapas in the east. Populations within regions, i.e., western or eastern Mexico, are separated by from 75 to 300 km, while the eastern and western populations are more that 700 km apart. Levels of gene flow between populations within regions and between eastern and western Mexico are assessed using the paternally inherited chloroplast genome as a marker. Twenty-five polymorphic restriction chloroplast sites were found in the 175 individuals surveyed; …

Plant Conservation In The Juan Fernandez Archipelago, Chile, Tod F. Stuessy, Ulf Swenson, Daniel J. Crawford, Gregory Anderson, Mario Silva O.

Aliso: A Journal of Systematic and Floristic Botany

Oceanic archipelagos often hold very specialized floras with high degrees of endemism. These floras are frequently highly vulnerable to disturbance by natural causes and human intervention. The Juan Fernandez Islands (Chile) in the Pacific Ocean are a small archipelago of only three islands. Since discovery in 1574 by Juan Fernandez, human activities have altered floristic composition and survival circumstances of the endemic species. In this paper we document past and present means of disturbance, both anthropogenic and natural, which have influenced the native vegetation. The most destructive past activities have been logging and .introduction of animals and plants, both deliberately …

Native And Naturalized Leguminosae (Fabaceae) Of The United States (Exclusive Of Alaska And Hawaii), Duane Isely

Books by Faculty of the Monte L. Bean Life Science Museum

Abstract

This work, in progress for five decades, consists of a summary revision of the legumes of the adjacent 48 United States. Treated are all known indigenous species, the commonly grown and weedy introductions, and some of the rarely grown species and waifs. Descriptions are provided for the legume family, for all genera, and for all indigenous and commonly grown or introduced species. Keys are provided for genera and species, as well as infraspecific taxa as required. Geographical information, distribution maps, and nomenclatural notes are included. New nomen­clatural proposals are as follows: Astragalus eastwoodiae var. debequaeus (Welsh) Isely, comb nov.; …

Characterization Of The Large (L) Rna Of Peanut Bud Necrosis Tospovirus, S. Gowda, Satyanarayana Tatineni, R. A. Naidu, A. Mushegian, W. O. Dawson, D. V. R. Reddy

Department of Plant Pathology: Faculty Publications

The nucleocapsids purified from peanut plants systemically infected with peanut bud necrosis virus (PBNV), a member of the genus Tospovirus, contained both viral(v) and viral complementary(vc) sense L RNAs. Defective forms of L RNA containing ‘core polymerase region’ were observed. The full length L RNA of PBNV was sequenced using overlapping cDNA clones. The 8911 nucleotide L RNA contains a single open reading frame (ORF) in the vc strand, and encodes a protein of 330 kDa. At the 50 and 30 termini of the v sense RNA there were 247 and 32 nt untranslated regions, respectively, containing an 18 …

Gas Chromatography/Mass Spectrometry Analysis Of The Cuticular Hydrocarbons From Parasitic Wasps Of The Genus Muscidifurax, Ulrich R. Bernier, David A. Carlson, Christopher J. Geden

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Parasitic Hymenoptera can be difficult to identify by conventional taxonomic techniques. Examination of the cuticular hydrocarbons (CHCs) provides a basis for chemotaxonomic differentiation, which may lead to the discovery of pheromones, and can be a means of examining colonies for species cross-contamination. The parasitic wasps examined were Muscidifurax raptor, M. zaraptor, M. uniraptor, and the gregarious form of M. raptorellus. Species within the genus Muscidifurax, as well as the sex, can clearly be differentiated by examining the gas chromatograms of the CHCs. Identification of the alkanes by mass spectrometry shows uncommon dimethylalkanes and trimethylalkanes for members of the …

Elution Patterns From Capillary Gc For Methyl-Branched Alkanes, David A. Carlson, Ulrich R. Bernier, Bruce D. Sutton

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

A common and confusing problem in analyses of insect hydrocarbons is in making sense of complicated gas chromatograms and interpreting mass spectra since branched chain compounds differing by one or two carbons in backbone or chain length may elute from the column at nearly the same time. To address this confusing situation, relative gas chromatography (GC) retention times are presented for typical mono-, di-, tri-, and tetramethylalkanes comprising most of the commonly appearing series of homologous methyl-branched alkanes up to 53 carbons that are found in insect cuticular hydrocarbons. Typical insect-derived methylalkanes with backbones of 33 carbons were characterized by …

Black Flies, Simulium Spp. (Insecta: Diptera: Simuliidae), J. F. Butler, J. A. Hogsette

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Introduction

Florida occasionally experiences outbreaks of black flies, though this is a rare occurance, and these large populations are caused by rainfall extremes. Common names for this pest include black flies and turkey gnats, as well as a number of new names applied by Floridians which are not repeatable here. Because of the hump visible behind their head when viewed in profile, black flies are also called buffalo gnats. Like eye gnats, they fly around people's heads, occasionally getting into eyes and ears as well as crawling in the hair. Because most of the specimens collected to date have been …

Spatial Pattern Of Gas Exchange For Montane Moist Meadow Species, Tony Svejcar, Gregg M. Riegel

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Montane moist meadows of western North America are relatively unique in that they are characterized by annual cycles of spring inundation followed by summer drought. Thus, plants adapted to these ecosystems must cope with a wide range of environmental conditions. We compared gas exchange and water relations of upper canopy leaves and leaf area index (LAI) of three dominant montane meadow graminoids growing at both streamside and mid-meadow locations (2.5 and 20.0 m, respectively from the stream edge). The two locations were environmentally very different in spite of their close proximity. The water table at the streamside location was ca. …

Physiology And Reproduction: Gross Appearance Of The Turkey Blastoderm At Oviposition, M. R. Bakst, S. K. Gupta, W. Potts, V. Akuffo

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

The blastoderm (fertilized ovum) and unfertilized germinal disc (UGD) of fresh laid eggs and eggs stored prior to incubation exhibit subtle but definable morphological variations. Such variations may lead to difficulty when attempting to determine true flock fertility based on the appearance of the blastoderm/UGD. The objectives of this study were to define and categorize such morphological variations and to determine whether sperm influence the frequency distribution of the different categories. Eleven categories of blastoderms were defined based on the relative density and appearance of the area alba, area pellucida, area opaca, and the periblast. The majority of the blastoderms …

Composition And Change Of Maritime Hammock Flora In East-Central Florida After 20 Years, Donald John Spence

Retrospective Theses and Dissertations

The vegetation of eight east-central Florida maritime hammocks studied in 1997 were compared to similar data collected over 20 years ago. Study sites are located in the northern half of the Indian River Lagoon system mostly within Canaveral National Seashore and Merritt Island National Wildlife Refuge. The upland hammock vegetation throughout the state generally has an oak-palm association, but here these species dominate. Results show that sabal palm, live oak, laurel oak, and pignut hickory, the four dominant tree species in 1976-77, are still dominant in 1997; however, there has been a loss in tree species richness. Most shrub species …

Northern Australia Quarantine Strategy. Weeds Target List, B. M. Waterhouse, A A. Mitchell

Biosecurity published reports

Second edition.

The Northern Australia Quarantine Strategy (NAQS) was established in 1989 as an outcome of a major evaluation of quarantine in Australia (AGPS 1987, 1988). NAQS activities include surveying for weeds,insect pests and diseases of plants; and pests and diseases of animals in northern Australia, Papua New Guinea and Indonesia. The primary goal is to provide early detection and warning of new quarantine threats or incursions.

A targetted approach was adopted for all pests, diseases and weeds. For each category of pest, experts in the discipline compiled lists of organisms not known from Australia but known to occur in …

The Three-Dimensional Structure Of Aspergillus Niger Pectin Lyase B At 1.7-Å Resolution1, Jacqueline Vitali, Brian Schick, Harry C.M. Kester, Jaap Visser, Frances Jurnak

Physics Faculty Publications

The three-dimensional structure of Aspergillus niger pectin lyase B (PLB) has been determined by crystallographic techniques at a resolution of 1.7 Å. The model, with all 359 amino acids and 339 water molecules, refines to a final crystallographic R factor of 16.5%. The polypeptide backbone folds into a large right-handed cylinder, termed a parallel b helix. Loops of various sizes and conformations protrude from the central helix and probably confer function. The largest loop of 53 residues folds into a small domain consisting of three antiparallel b strands, one turn of an a helix, and one turn of a 310 …

Economic Importance Of Managing Spatially Heterogeneous Weed Population, John L. Lindquist, J. Anita Dieleman, David A. Mortensen, Gregg A. Johnson, Dawn Y. Wyse-Pester

Department of Agronomy and Horticulture: Faculty Publications

Three methods of predicting the impact of weed interference on crop yield and expected economic return were compared to evaluate the economic importance of weed spatial heterogeneity. Density of three weed species was obtained using a grid sampling scheme in 11 corn and 11 soybean fields. Crop yield loss was predicted assuming densities were homogeneous, aggregated following a negative binomial with known population mean and k, or aggregated with weed densities spatially mapped. Predicted crop loss was lowest and expected returns highest when spatial location of weed density was utilized to decide whether control was justified. Location-specific weed management resulted …

Floristic Inventory Of Three Bogs On Crowley's Ridge In Arkansas, Staria S. Vanderpool, Edward Leon Richards

Journal of the Arkansas Academy of Science

A floristic inventory of vascular plant taxa of three wetlands known locally as bogs on Crowley's Ridge in Greene and Clay counties was conducted from August 1979 to July 1981. Total combined area of the three sites was 9.2 ha with a range from 2.3 ha to 4.3 ha. Overall 360 taxa representing 227 genera and 92 families were collected from the bogs and surrounding upland forest and identified. Plant taxa from bog sites ranged from 81 to 89 species with 35 species collected from all 3 bogs and 26 found in 2 of the 3 sites. Among the taxa …

Intrapopulation Sex Ratio Variation In The Salt Grass Distichlis Spicata, Sarah M. Eppley, Maureen L. Stanton, Richard K. Grosberg

Biology Faculty Publications and Presentations

In many dioecious plant populations, males and females appear to be spatially segregated, a pattern that is difficult to explain given its potentially high costs. However, in asexually propagating species, spatial segregation of the sexes may be indistinguishable from superficially similar patterns generated by random establishment of a few genets followed by extensive clonal spread and by gender-specific differences in rates of clonal spread. In populations where a significant fraction of individuals are not flowering and gender cannot be assigned to this fraction, apparent spatial segregation of the sexes may be due to differential flowering between the sexes. We confirm …

Genetic Markers In Plant Evolutionary Ecology, Mitchell B. Cruzan

Biology Faculty Publications and Presentations

Genetic markers have provided plant ecologists with a method of assessing levels of genetic relatedness among individuals and populations. In recent years a number of techniques based on DNA sequence variation have been developed to complement allozyme methods that are already widely used. Some of these new markers are more variable than protein-based markers, allowing more precise estimates of genetic differences among individuals and populations. Other DNA-based markers are based on organelle genomes that are inherited uniparentally. These cytoplasmic markers can provide a method for assessing the separate effects of seed and pollen dispersal on gene flow within and among …

The In Vitro Propagation Of Seagrasses : Halophila Ovalis, Ruppia Megacarpa And Posidonia Coriacea, Melissa Grace Henry

Theses : Honours

Seagrass communities are of high ecological and economic significance. They provide a nursery area for commercial and recreational juvenile fish and crustacea. Seagrasses also play an important role in influencing the structure and function of many estuarine and nearshore marine environments. Unfortunately, the decline of seagrasses, as a result of human impact, has increased in recent years. This decline has become a major problem throughout the world. Current methods used to restore degraded seagrass beds are limited, the most promising being transplanting material from healthy donor beds. This approach is expensive because it is labor intensive and damages the donor …

Development And Biological Assessment Of Fortified Foods With Andean Tubercles In The Candelaria Area, María Lourdes Ovando Sejas

Theses and Dissertations

Development and Biological Assessment of Fortified Foods with Andean Tubercles and other products in the Candelaria Area. An alimentation survey was carried out in the Rodeo Alto-Candelaria zone, a producing region of tubercle andinos, and a list was made of available products and other products which are a part of the local diet. With the list as the basis, 12 mixes were formed, combining tubercle (potato, goose, papalisa), cereals (quinoa, corn, and wheat) and legumes (tarhui, bean, and peanut). These mixes were submitted to a chemical and biological analysis, which indicated an increase in weight, PER, digestibility of the protein …