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Alien Invaders: Envisioning Exotic Species In Florida, Kevin Archer Jan 1997

Alien Invaders: Envisioning Exotic Species In Florida, Kevin Archer

All Faculty Scholarship for the School of Graduate Studies and Research

No abstract provided.

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Leafy Spurge - A Review, Sharon A. Clay, Chad M. Scholes Jan 1997

Leafy Spurge - A Review, Sharon A. Clay, Chad M. Scholes

Agronomy, Horticulture and Plant Science Faculty Publications

Leafy spurge (Euphorbia esula L.) is a perennial herbaceous weed that infests millions of acres of range and pasture in the northern Great Plains. It outcompetes grasses and lowers land productivity because cattle will not graze infested areas even if spurge makes up only 10% of the vegetative biomass. This presentation will cover the history, taxonomy, and phenology of leafy spurge. A discussion of chemical, mechanical, and biocontrol techniques that aid in leafy spurge management will also be included.

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Analysis Of Spatial Distribution Of Canada Thistle (Cirsium Arvense) In Notill Soybean (Glycine Max), B. L. Broulik, J. Lems, S. A. Clay, D. E. Clay, M. M. Ellsbury Jan 1997

Analysis Of Spatial Distribution Of Canada Thistle (Cirsium Arvense) In Notill Soybean (Glycine Max), B. L. Broulik, J. Lems, S. A. Clay, D. E. Clay, M. M. Ellsbury

Agronomy, Horticulture and Plant Science Faculty Publications

The nonuniform spatial distribution of weeds across a field landscape complicates sampling and modeling, but allows site specific rather than broadcast management of weed populations. Where weeds are aggregated, densities measured at random locations are not independent, but rather spatially related or autocorrelated. Geostatistical methods were used to describe and map nonrandom distribution and variation of shoot density across ten well established patches of Canada thistle, a perennial weed, in a 65 hectare notillage soybean field in Moody county, South Dakota in 1996. Canada thistle densities were determined by counting the number of shoots present in a 20 by 50 …

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Between A Rock And A Hard Place: Opuntia Fragilis (Nutt.) Haw. (Cactaceae) In Stearns County, Minnesota, Eric Ribbens, Jeremy Myrom Jan 1997

Between A Rock And A Hard Place: Opuntia Fragilis (Nutt.) Haw. (Cactaceae) In Stearns County, Minnesota, Eric Ribbens, Jeremy Myrom

Journal of the Minnesota Academy of Science

We surveyed the distribution of Opuntia fragilis ( Nutt.) Haw. in Steam County, MN, where it is restricted to a few rock outcrops. To compare the populations within three sites, we mapped clusters of pads and measured each individual pad within each cluster. Pads tended to be located in a narrow band of shallow soil between the bare rock and the angiosperm-dominated plant communities growing on adjacent deeper soils. Significant differences existed between the three populations in pad widths, average pad cluster sizes, and pad appearances. Although several pads flowered, none of the flower set seed, indicating that persistence of …

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Factors Affecting Atrazine Fate In North Central U.S. Soils, W. C. Koskinen, Sharon Clay Jan 1997

Factors Affecting Atrazine Fate In North Central U.S. Soils, W. C. Koskinen, Sharon Clay

Agronomy, Horticulture and Plant Science Faculty Publications

Atrazine (6-chloro-N-ethyl-N′-(l-methylethyl)-l,3,5-triazine-2,4-diamine) is a herbicide of the triazine family used for controlling broadleaf and some grassy weeds in corn and sorghum. Since its introduction in the late 1950s, atrazine has been a popular herbicide because it is relatively inexpensive and, in most cases, gives good season-long weed control. It can be applied pre-or postemergence and is often tank mixed with grass herbicides, such as alachlor (2-chloro-N-(2,6-diethylphenyl-N-(methoxymethyl)acetamide), metolachlor(2-chloro-N-(2-2ethyl-6-methylphenyl)-N-(2-methoxy-l-methylethyl) acetamide), butylate (S-ethyl bis(2-methylpropyl)carbamothioate), or EPTC (S-ethyl dipropylcarbamothioate), or with other broadleaf herbicides, such as dicamba (3,6-dichloro-2-methoxybenzoic …

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Selective Predation On The Seeds Of Woody Plants, Scott J. Meiners, Edmund W. Stiles Jan 1997

Selective Predation On The Seeds Of Woody Plants, Scott J. Meiners, Edmund W. Stiles

Faculty Research & Creative Activity

Selective predation on the seeds of woody plants. J. Torrey Bot. Soc. 124: 67-70). 1997.-Seed predation may be an important factor influencing the structure of successional plant communities. We used a cafeteria-style experiment, placed in an old field and an early successional forest, to determine predator preferences for seeds of nine species of woody plants. Intensity of seed predation was equivalent in both sites. Seed predators preferred Acer saccharum, flex vertic illata, and Viburnum dentatum, but this was not related to seed mass. Predation intensity was more variable in the old field than in the forest, possibly related to the …

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Exploring Alternative Systems Of Classification, Kathleen A. Kron Jan 1997

Exploring Alternative Systems Of Classification, Kathleen A. Kron

Aliso: A Journal of Systematic and Floristic Botany

Classification involves the development of a system of naming clades that can represent evolutionary relationships accurately and concisely. Using the acid-loving heath plants (Ericales) as an example, one can explore the application of different classification methods. The Linnean system of naming retains the traditional hierarchical framework (named ranks) and allows for the application of many cuqently used names. The "phylogenetic systematic" approach recommends the removal of an absolute hierarchy but allows retention of traditionally used endings such as -aceae. Historical usage of these names can lead to confusion when the names are used within a discussion or text, especially when …

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A Biosystematic Survey Of Sierra Lodgepole Pine (Pinus Contorta Var. Murrayana [Critchfield]) Populations In The Transverse And Peninsular Ranges Of Southern California, Richard Gobin Everett Jan 1997

A Biosystematic Survey Of Sierra Lodgepole Pine (Pinus Contorta Var. Murrayana [Critchfield]) Populations In The Transverse And Peninsular Ranges Of Southern California, Richard Gobin Everett

Theses Digitization Project

No abstract provided.

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Conidial Germination And Infection By Diplocarpon Rosae On Susceptible And Resistant Rose Species, Robert J. Wiggers, J. G. West, Josephine Taylor Jan 1997

Conidial Germination And Infection By Diplocarpon Rosae On Susceptible And Resistant Rose Species, Robert J. Wiggers, J. G. West, Josephine Taylor

Faculty Publications

Conidial germination and infection by Dipplocarpon rosae, the causal organism of rose blackspot, were examined on two resistant species of roses, Rosa roxburghii and R. wichuraiana and two susceptible hybrid tea roses (R. hybrid cv. Chicago Peace and Garden Party). Fungal conidia germinated and gave rise to subcuticular mycelium that formed haustoria within epidermal cells of all four roses tested. On the resistant rose species, epidermal cells associated with the infection site became necrotic, indicating that a hypersensitive response is involved in conferring their resistance D. rosae.

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Selective Predation On The Seeds Of Woody Plants, Scott Meiners, Edmund Stiles Jan 1997

Selective Predation On The Seeds Of Woody Plants, Scott Meiners, Edmund Stiles

Faculty Research & Creative Activity

Selective predation on the seeds of woody plants. J. Torrey Bot. Soc. 124: 67-70). 1997.-Seed predation may be an important factor influencing the structure of successional plant communities. We used a cafeteria-style experiment, placed in an old field and an early successional forest, to determine predator preferences for seeds of nine species of woody plants. Intensity of seed predation was equivalent in both sites. Seed predators preferred Acer saccharum, flex vertic illata, and Viburnum dentatum, but this was not related to seed mass. Predation intensity was more variable in the old field than in the forest, possibly related to the …

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Observations On Pasture Management And Grazing, Darwin B. Nielsen Jan 1997

Observations On Pasture Management And Grazing, Darwin B. Nielsen

All Archived Publications

No abstract provided.

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An Analysis Of The Variation Within Cratoxylum Arborescens (Clusiaceae) In Malesia, A.C. Church, P.F. Stevens Jan 1997

An Analysis Of The Variation Within Cratoxylum Arborescens (Clusiaceae) In Malesia, A.C. Church, P.F. Stevens

Biology Department Faculty Works

The variation within the widespread West Malesian species Cratoxylum arborescens (Vahl) Blume was analyzed and three distinctive variants were found. These are recognized formally as varieties, var. arborescens, var. miquelii King, and var. borneense A.C. Church & P.F. Stevens. A key and full descriptions are given. The characters employed to delimit the three taxa are discussed and the selection of varietal rank is justified.

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Two New Species Of Uncinia (Cyperaceae) From Chile, Gerald A. Wheeler Jan 1997

Two New Species Of Uncinia (Cyperaceae) From Chile, Gerald A. Wheeler

Aliso: A Journal of Systematic and Floristic Botany

Two new species of Uncinia (Cyperaceae) are described from Chile. Both are local endemics, with U. chilensis known from VIII (Bío Bío) and IX (Araucanía) regións of central Chile and U. araucana from IX Región only.

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Phylogeny Of Polemoniaceae Based On Nuclear Ribosomal Internal Transcribed Spacer Dna Sequences, J. Mark Porter Jan 1997

Phylogeny Of Polemoniaceae Based On Nuclear Ribosomal Internal Transcribed Spacer Dna Sequences, J. Mark Porter

Aliso: A Journal of Systematic and Floristic Botany

Nuclear ribosomal internal transcribed spacer (ITS) DNA sequences are used to estimate the phylogeny of 53 members of Polemoniaceae, representing all but two genera of the family. Fitch parsimony analysis of equal-weighted nucleotide sites result in 1080 minimal-length trees. However, when alignment-ambiguous positions are removed and an II: 10 transition to transversion weighting is imposed only eight trees are found. These data are used to address two issues: I) patterns of diversification in Polemoniaceae, and 2) the circumscription and monophyly of the genus Gilia. Although the monophyly of Polemoniaceae is well supported, relationships inferred among the earliest diverging lineages …

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Hierarchial Roots And Shoots Or Opera Jehovae Magna! (Psalms 111:2), Dan H. Nicolson Jan 1997

Hierarchial Roots And Shoots Or Opera Jehovae Magna! (Psalms 111:2), Dan H. Nicolson

Aliso: A Journal of Systematic and Floristic Botany

The philosophy of Linnaeus's classification, Systema Naturae, is briefly reviewed, as well as those of post-Linnaean systems of plant classification. Texts of current codes of nomenclature pertaining to hierarchy, including associated rank terminations, are compared.

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Problems In Cladistic Classification: Higher-Level Relationships In Land Plants, Peter R. Crane, Paul Kenrick Jan 1997

Problems In Cladistic Classification: Higher-Level Relationships In Land Plants, Peter R. Crane, Paul Kenrick

Aliso: A Journal of Systematic and Floristic Botany

Recent cladistic analyses of green plants recognize an extensive hierarchical series of relatively well-supported monophyletic groups. Translating this hierarchical pattern of relationships into a usable and informative written classification is important for purposes of scientific communication, research and teaching. However, in the context of the "Linnean" hierarchy, as manifested in the current International code of Botanical Nomenclature (ICBN), effecting this translation confronts substantial practical difficulties--especially the proliferation of hierarchical levels. These problems are exacerbated by the current emphasis of the ICBN on a hierarchy in which different ranks have different formal rank-based endings. These difficulties could be ameliorated by de-emphasizing …

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Classification: More Than Just Branching Patterns Of Evolution, Tod F. Stuessy Jan 1997

Classification: More Than Just Branching Patterns Of Evolution, Tod F. Stuessy

Aliso: A Journal of Systematic and Floristic Botany

The past 35 years in biological systematics have been a time of remarkable philosophical and methodological developments. For nearly a century after Darwin's Origin of Species, systematists worked to understand the diversity of nature based on evolutionary relationships. Numerous concepts were presented and elaborated upon, such as homology, parallelism, divergence, primitiveness and advancedness, cladogenesis and anagenesis. Classifications were based solidly on phylogenetic concepts; they were avowedly monophyletic. Phenetics emphasized the immense challenges represented by phylogeny reconstruction and advised against basing classifications upon it. Pheneticists forced reevaluation of all previous classificatory efforts, and objectivity and repeatability in both grouping and …

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Bulletin 4332 - Establishing Table Grapes In The South-West, J. Campbell-Clause, A. Price, P. Gartrell Jan 1997

Bulletin 4332 - Establishing Table Grapes In The South-West, J. Campbell-Clause, A. Price, P. Gartrell

Bulletins 4000 -

This Bulletin provides a starting point for prospective table grape growers and highlights factors to consider before establishing a table grape planting in the south­west of Western Australia. The requirements for establishing wine and table grapes vary considerably, including site selection, water requirements, varieties, management techniques, costs and marketing options.

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Center For Grassland Studies Newsletter, Winter 1997, Volume 3, No. 1 Jan 1997

Center For Grassland Studies Newsletter, Winter 1997, Volume 3, No. 1

Center for Grassland Studies: Newsletters

Contents:

New Nutritional Information For Beef Producers in 1997 Nebraska Beef Report by Dennis Brink, Department of Animal Science, UNL

IANR Employees Recognized at Nebraska Turfgrass Conference

New CAST report: Grazing on Public Lands

Pasture Songbirds by Laura Paine and Dan Undersander, Department of Agronomy, University of Wisconsin

U.S. Forest Service Revising Grassland Management Plans by Tom Domek, Nebraska National Forest

Sandhills Partnership Receives Grant for Fen Restoration

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Nebline, January 1997 Jan 1997

Nebline, January 1997

NEBLINE Newsletter Archive from Nebraska Extension in Lancaster County

Agribusiness education: a priority for Extension!
NEBLINE survey completed
Disease-resistant plants
The most common houseplant disease
Over the garden fence
Plants to decrease indoor pollution
New 4-H horticulture classes for Lancaster County Fair
New 4-H horticulture garden program
Tree hotel
Illegal insecticide use threatens health
Hibernation happenings
Newly-discovered magnet producing bacteria may clean environment
January is nota slow month for some pesky pests
Are any two alike? Snowflakes
Snug in the snow
Crop protection clinics
Pork production seminar
Cash in on hay marketing opportunities
Dormant planting grasses and legumes
1997 pesticide applicator training
Use soil tests to improve alfalfa production …

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A Comparative Study Of The Benthic Population In Weir Ponds Draining Watersheds Of The Fernow Experimental Forest, Parsons, West Virginia, Kevin Dwayne Brittingham Jan 1997

A Comparative Study Of The Benthic Population In Weir Ponds Draining Watersheds Of The Fernow Experimental Forest, Parsons, West Virginia, Kevin Dwayne Brittingham

Theses, Dissertations and Capstones

A study of the benthos of weir ponds draining watersheds of the Fernow Experimental Forest (FEF) was conducted in 1994-1995. The objectives of this study were: (1) to relate differences in weir pond faunas to watershed treatments on the FEF, and (2) to compare current weir pond faunas to those described in 1973 by Steve Harris. In 1971-1972, there were fewer invertebrates but greater taxa richness than in 1994-1995. Total density varied among weir pond and between studies with numbers in the 1971- 1972 study ranging from 26,168 to 79,259 individuals collected, while numbers in the 1994-1995 study raged from …

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Floristic Investigation Of Crooked Creek Community Of Juan Solomon Park, Indianapolis Indiana, Raelene M. Crandall, Rebecca W. Dolan Jan 1997

Floristic Investigation Of Crooked Creek Community Of Juan Solomon Park, Indianapolis Indiana, Raelene M. Crandall, Rebecca W. Dolan

Scholarship and Professional Work - LAS

The protection of plant resources in urban areas is a growing conservation concern. Inventory activities that document species presence and stewardship plans that protect and enhance these areas are needed. The results of a botanical inventory of the Crooked Creek Community Juan Solomon Park in Indianapolis, Indiana, are reported in this paper. The 46-acre park contains three distinct habitats, supporting a wide variety of plants. One hundred seventy-nine vascular plant species from 64 families were identified, including 53 (29.6%) non-native species that are naturalizing within the park. Despite its high percentage of alien species and urban setting, the park is …

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The Euphorbiaceae Of Sonora, Mexico, Victor W. Steinmann, Richard S. Felger Jan 1997

The Euphorbiaceae Of Sonora, Mexico, Victor W. Steinmann, Richard S. Felger

Aliso: A Journal of Systematic and Floristic Botany

This publication is an account of the Euphorbiaceae in the state of Sonora, México. Nineteen genera, 143 species, and three additional varieties are recorded for the state; three species expected within the state are also treated. One species of Acalypha and three species and one subspecies of Euphorbia are described. Dichotomous keys for the identification of genera and species are provided. Bibliographic citations, type information, synonyms, brief habit descriptions, times of reproduction, habitat preferences as well as elevational range within Sonora, geographical distribution, and representative specimens are given for each species. When appropriate, notes on uses, taxonomic or nomenclatural problems, …

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Uncinia (Cyperaceae) Of Ecuador, Gerald A. Wheeler, Paul Goetghebeur Jan 1997

Uncinia (Cyperaceae) Of Ecuador, Gerald A. Wheeler, Paul Goetghebeur

Aliso: A Journal of Systematic and Floristic Botany

Nine species of Uncinia (Cyperaceae: Caricoideae) are recorded from Ecuador, one of which, U. ecuadorensis, is newly described and illustrated here. Descriptions, illustrations, distribution maps, and both artificial and vegetative keys are provided for the nine species, and for some uncinias additional taxonomic, phytogeographic and ecological comments are made. A lectotype is designated for the name U. lenuis.

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Prediction Of Potential Antimigraine Activity Using Artificial Neural Networks, Qing Luo, Jerry A. Darsey, Cesar M. Compadre, Sanjay K. Mitra Jan 1997

Prediction Of Potential Antimigraine Activity Using Artificial Neural Networks, Qing Luo, Jerry A. Darsey, Cesar M. Compadre, Sanjay K. Mitra

Journal of the Arkansas Academy of Science

More than 10 million Americans, three quarters of them women, suffer some degree of recurrent migraine headaches. Feverfew [Tanacetum parthenium (L.) Schultz-Bip.) is a member of the Asteraceae family that is native to Europe. This plant is a perennial flowering aromatic plant common in gardens. It has been widely used as a self-medication of arthritis, fever, and migraine headaches for over 2000 years. Sesquiterpene lactones (SL) are the components responsible for the antimigraine activity of feverfew. In this research, the relationship between SL structural information and their biological activity was studied by using Gaussian 92 program in conjunction with artificial …

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Ground Flora Composition Following Harvesting Of A Bottomland Hardwood Forest In The Mississippi River Batture Lands, James E. Kellum, Eric Sundell, Brian Roy Lockhart Jan 1997

Ground Flora Composition Following Harvesting Of A Bottomland Hardwood Forest In The Mississippi River Batture Lands, James E. Kellum, Eric Sundell, Brian Roy Lockhart

Journal of the Arkansas Academy of Science

No abstract provided.

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Rediscovery Of Parnassia Asarifolia Vent (Parnassiaceae) In Arkansas, David L. Mcdaniel, Daniel L. Marsh, Winfred D. Crank Jan 1997

Rediscovery Of Parnassia Asarifolia Vent (Parnassiaceae) In Arkansas, David L. Mcdaniel, Daniel L. Marsh, Winfred D. Crank

Journal of the Arkansas Academy of Science

No abstract provided.

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Can Denitrification Reduce No3 In Shallow Ground Water?, Mark S. Coyne, E. Montgomery, Grant W. Thomas Jan 1997

Can Denitrification Reduce No3 In Shallow Ground Water?, Mark S. Coyne, E. Montgomery, Grant W. Thomas

Agronomy Notes

Systematic sampling of springs, tiles, and wells in Kentucky, as part of a recent statewide program to assess agricultural impacts on water quality, showed that NO3 concentrations in these shallow ground water sources varied tremendously. The NO3 concentration could be correlated with flow rate; higher when ground water recharge flushed NO3 from soil in winter and spring, and lower or non detectable in summer and fall when less NO3 leaching occurred. Depending on the season, NO3 concentrations ranged from < 1 to > 10 ppm NO3-N in almost half of the sites. For example, the water in …

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Biological Species Concepts In Eastern North American Populations Of Lentinellus Ursinus, Andrew N. Miller Jan 1997

Biological Species Concepts In Eastern North American Populations Of Lentinellus Ursinus, Andrew N. Miller

Masters Theses

As part of a biosystematic study of the Lentinellus ursinus species complex, field and herbarium specimens from North America, Central America, and Europe were examined. Single basidiospore isolates from basidiomata collected in Illinois, Indiana, Iowa, Michigan, Minnesota, Missouri, Tennessee, North Carolina, Wisconsin, Costa Rica, and Austria were crossed in all possible combinations to determine the mating system operating in each population. All populations exhibited bifactorial or tetrapolar mating systems. Tester strains were then crossed to identify intercompatible populations and to determine if morphological species in the L. ursinus species complex are congruent with biological species. Three biological species were recognized …

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Parade Of Presidents, John L. Artz Jan 1997

Parade Of Presidents, John L. Artz

Aspen Bibliography

No abstract provided.

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