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Growth And Year Class Composition Of The White Bass (Morone Chrysops) In Degray Lake, Arkansas, Thomas E. Moen, Michael R. Dewey Jan 1980

Growth And Year Class Composition Of The White Bass (Morone Chrysops) In Degray Lake, Arkansas, Thomas E. Moen, Michael R. Dewey

Journal of the Arkansas Academy of Science

No abstract provided.


Occurrence And Characteristics Of Nonfruiting Myxobacteria Isolated From Pine Forest Soils, Paul M. Kulvi Jan 1980

Occurrence And Characteristics Of Nonfruiting Myxobacteria Isolated From Pine Forest Soils, Paul M. Kulvi

All Master's Theses

A study was conducted to contribute to the taxonomy of the nonfruiting myxobacteria and to determine the effects of fire on the occurrence and characteristics of nonfruiting myxobacteria isolated from pine forest soil Three years after a prescribed burn, the population of nonfruiting myxobacteria was decreased in the burn site. The organisms isolated were distinct from any of the known species of nonfruiting myxobacteria, and apparently are new species.


Sex Change In Plants: Old And New Observations And New Hypotheses, D.C. Freeman, K.T. Harper, Eric Charnov Jan 1980

Sex Change In Plants: Old And New Observations And New Hypotheses, D.C. Freeman, K.T. Harper, Eric Charnov

Biology Faculty & Staff Publications

Evidence is presented that individuals of a large number of dioecious and subdioecious plant species are able to alter their sexual state in response to changes in the ambient environment and/or changes in size or age. We suggest that lability of sexual expression probably has survival value where a significant portion of the females must otherwise bear the cost of fruit production in unfavorable environments. We demonstrate that in patchy environments of the proper scale and variability in quality, labile sexual expression will enhance an individuals genetic contribution to the next generation.


Specimen Catalog, James C. Bednarz Jan 1980

Specimen Catalog, James C. Bednarz

Division of Mammals - Field Notes and Catalogs

No abstract provided.


Platte River Evapotranspiration: A Historical Perspective In Central Nebraska, Harold G. Nagel, M. Stanley Dart Jan 1980

Platte River Evapotranspiration: A Historical Perspective In Central Nebraska, Harold G. Nagel, M. Stanley Dart

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

A computational model was developed to estimate evapotranspiration (ET) in the Platte River ecosystem of central Nebraska. Data used in the model were mostly derived from the literature, although leaftemperature data were collected to estimate species transpirationcoefficients.

Preliminary estimates for ET are 35.5 in per yr during the April-tooctober growing season. Riparian forest accounted for 30% of the total ET, followed in order of importance by open-water evaporation, forested islands, herbaceous riparian-transpiration, sandbar evaporation, and then hcrbaceous island-vegetation, which accounted for only 10% of the total ET.

The Platte River has changed markedly during the last 40 years, with reduced …


Observations On The Life Cycle Of Spurge Hawkmoth, J. R. Forwood, M. K. Mccarty Jan 1980

Observations On The Life Cycle Of Spurge Hawkmoth, J. R. Forwood, M. K. Mccarty

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

Certain aspects of the life cycle of the spurge hawkmoth, Hyles euphorbiae L. (Sphingidae), were studied to evaluate it as a possible biological control agent for leafy spurge (Euphorbia esula L.) in Nebraska. There are five phases in the life cycle of this insect: egg, larva, prepupa, pupa, and adult. It is a foliage-feeding insect and consumes about 18 g fresh weight of leafy spurge during its larval life. About 80% of the leafy spurge consumption is by the fifth instar. A generation may be completed in a period of 42 to 72 days. The spurge hawkmoth overwinters as …


Platte River Island Succession, Harold G. Nagel, Karen Geisler, John Cochran, Jon Fallesen, Barbara Hadenfeldt, Joy Mathews, John Nickel, Steven Stec, Alice Walters Jan 1980

Platte River Island Succession, Harold G. Nagel, Karen Geisler, John Cochran, Jon Fallesen, Barbara Hadenfeldt, Joy Mathews, John Nickel, Steven Stec, Alice Walters

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

This study was designed to determine successional trends of soils and vegetation on Platte River islands in central Nebraska and to elucidate interactions between them through time.

Twenty study islands from five age-size classes were randomly selected in a 48 km stretch near Kearney, Nebraska. The age of islands wao determined by use of aerial photographs. Woody and herbaceous plant species were sampled systematically, and soil cores were analyzed for organic matter and texture at each island. Relative elevation at each sampling plot was determined.

There were 20 islands per linear kilometer in the study area larger than 0.04 ha …


Distribution Of Fishes In Thirty-Two Mile Creek, Nebraska, Steven R. Walker Jan 1980

Distribution Of Fishes In Thirty-Two Mile Creek, Nebraska, Steven R. Walker

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

Thirty-two Mile Creek drains a 276 km2 area in south central Nebraska as a tributary to the Little Blue River. Fishes were collected during the summer of 1977 using a seine. Nine species were collected at the 16 stations sampled.

The fathead minnow (Pimephales promelas) was the most abundant species and present at every station. Black bullhead (lctalurus melas), carp (Cyprinus carpio), and red shiner (Notropis lutrensis) were widespread while other species had limited distributions. Species diversity was determined for each station and stream order. Fish distribution and abundance in the drainage were …


Causality, Determinism, And The Mind-Brain Problem, Jeffrey C. Schank Jan 1980

Causality, Determinism, And The Mind-Brain Problem, Jeffrey C. Schank

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

The problem of causality, determinism, and mind and brain are discussed, and new solutions are offered. To begin, a pragmatic structuralism is assumed, asserting the functional equivalence of mind and brain activity. A problem-solving model of mind-brain activity is defined, employing the mathematical theory of probablistic automata. With this model it can be determined whether mind-brain activity is deterministic. This is accomplished if an adequate definition of strict causality is developed. Logical models of strict causality which define the causal relation in terms of "material implication" or "strict implication" are rejected. Causal relativity is assumed, and certain systemtheoretical assumptions are …


The Idea Of Technological Progress And Its Problems, Eugene E. Selk Jan 1980

The Idea Of Technological Progress And Its Problems, Eugene E. Selk

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

Recently the problem of scientific progress has been one of the most widely discussed topics among historians and philosophers of science. But little has been said on the problem of technological progress. I suggest that theories of technological progress can be divided, first, into cognitive and non-cognitive; then cognitive can be subdivided into cumulative and problem-solving; non-cognitive can be divided into material well-being and moral and spiritual well-being. After examining different versions of the cumulative theory, I conclude that technology is not intrinsically cumulative; whether technology is cumulatively progressive is a matter of goals extrinsic to technology. I argue that …


Transactions Of The Nebraska Academy Of Sciences Volume Viii (1980): Table Of Contents Jan 1980

Transactions Of The Nebraska Academy Of Sciences Volume Viii (1980): Table Of Contents

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

Nebraska Academy of Sciences, Officers, Policy Committee .......... ii

Editorial Board, Instructions to Contributors .......... v

Membership Objectives and Friends of the Academy .......... vi

Biological and Medical Sciences

The influence of winglessness on mating frequency in species of the Drosophila affinis subgroup (Alemdar, McIntyre, Chang, and Miller) .......... 1

Den and den-site characteristics of coyotes (Canis latrans) in southeastern Nebraska (D. P. Althoff) .......... 9

Floristic analysis of a natural area on the Lower Platte River Flood Plain (D. A. Becker) .......... 15

Observations on the life cycle of spurge hawkmoth (J. R. Forwood and M. K. …


The Influence Of Winglessness On Mating Frequency In Species Of The Drosophila Affinis Subgroup, Neriman Alemdar, Ronda Mcintyre, Ho-Chi Chang, Dwight D. Miller Jan 1980

The Influence Of Winglessness On Mating Frequency In Species Of The Drosophila Affinis Subgroup, Neriman Alemdar, Ronda Mcintyre, Ho-Chi Chang, Dwight D. Miller

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

Certain Drosophila species that cannot mate in darkness have also been shown to be unable to mate in the light if their wings have been removed, perhaps due to the fact that wings provide visual signs and signals for courtship. To determine the influence of winglessness on mating in light-dependent Drosophila algonquin and its relatives, we determined mating frequencies in combinations of winged and wingless individuals of the six widespread American Drosophila affinis subgroup species D. affinis, D. algonquin, D. athabasca, D. azteca, D. narragansett, and D. tolteca. In no case did winglessness of …


Floristic Analysis Of A Natural Area On The Lower Platte River Flood Plain, Donald A. Becker Jan 1980

Floristic Analysis Of A Natural Area On The Lower Platte River Flood Plain, Donald A. Becker

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

The vascular flora of an extinct river-island and inactive northchannel of the Platte River was studied from 1972-1978. Within a variety of vegetation types, including seral and sub climax flood plain forests, 289 species were identified from 200 genera and 70 families. The flora is dominated by four families, the Poaceae, Asteraceae, Cyperaceae, and Fabaceae, which contribute 40% of the species. Forty-eight species of woody plants occur in the area, including 17 species not previously reported in Dodge County. While much of the flora is composed of forest species (36.1%), significant numbers of ruderal and marsh species (each 19.4%) are …


The Fishes Of Salt Creek Basin, Nebraska, Terry R. Maret, Edward J. Peters Jan 1980

The Fishes Of Salt Creek Basin, Nebraska, Terry R. Maret, Edward J. Peters

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

During April through October 1977 we investigated the distribution of stream fishes from Salt Creek Basin in southeastern Nebraska. A total of 18,560 individuals representing 12 families and 34 species was taken from 125 collections at 102 different localities. Each collected species is reported in the form of an annotated list. Pimephales promelas, Notropis stramineus, N. lutrensis, Lepomis cyanellus. and Ictalurus melas were most frequently collected. The general low diversity of fish species at most collection sites indicates that the environment in these small streams is quite unstable. Comparisons with previous surveys of the fish fauna in …


Paleoclimatic Implications Of Pleistocene Herpetofaunas Of Eastern And Central North America, J. Alan Holman Jan 1980

Paleoclimatic Implications Of Pleistocene Herpetofaunas Of Eastern And Central North America, J. Alan Holman

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

A review of Pleistocene herpetofaunas of eastern and central North America does not support the classical concept of alternating cool-moist, warm-dry glacial and interglacial climates. On the contrary, herpetological evidence generally indicates Pleistocene climates south of the glacial boundaries were warmer or more equable than today until very Late Pleistocene time, when there is some evidence of cooling in the Ozark and Appalachian areas. On the other hand, there is evidence that climatic equability persisted in southern Texas, northeastern Mississippi, northwestern Georgia, and Florida, in very Late Pleistocene time. Since classical terms such as Nebraskan, Aftonian, Kansan, etc., reflect the …


The Diet Of The Florida Pompano (Trachinotus Carolinus) Along The East Coast Of Central Florida, Thomas M. Armitage, William S. Alevizon Jan 1980

The Diet Of The Florida Pompano (Trachinotus Carolinus) Along The East Coast Of Central Florida, Thomas M. Armitage, William S. Alevizon

Ocean Engineering and Marine Sciences Faculty Publications

The diet of the Florida pompano (Trachinotus carolinus) was investigated by examining stomach contents of adults from the Indian River and juveniles from the surf zone off Brevard County. Juveniles consumed primarily henthic crustaceans, mainly Emerita talpoida, and the bivalve, Donax variabilis. The diet of the adults consisted mainly of bivalve molluscs in the families Tellinidae, Mactridae, and Arcidae. In comparison with juveniles, the adults displayed a decrease in the number of planktonic organisms that are selected as prey items. Availability of prey appears to be more important than caloric content of prey in determining the diet of T. carolinus. …


Honeydew Excretion Measurement Techniques For Determining Differential Feeding Activity Of Biotypes Of Nilaparvata Lugens On Rice Varieties, P. Paguia, M. D. Pathak, E. A. Heinrichs Jan 1980

Honeydew Excretion Measurement Techniques For Determining Differential Feeding Activity Of Biotypes Of Nilaparvata Lugens On Rice Varieties, P. Paguia, M. D. Pathak, E. A. Heinrichs

Department of Entomology: Faculty Publications

Techniques to quantify the feeding activity of Nilaparvata lugens (Stål) on rice varieties as based on honeydew excretion are described, and their potential as a bioassay for biotype identification are discussed. Honeydew, excreted on filter paper, was stained with ninhydrin and quantified by measuring the area (mm2) or by weighing. Results were satisfactory but the methods were extremely tedious. Volumetric measurement of honeydew with micropipettes was less sensitive. The color intensity of one μliter honeydew streaked on filter paper and treated with 0.001% ninhydrin was determined with a Fujiox Densitometer. The method was relatively simple and rapid …


Quantitative Demonstration Of Cell Surface Involvement In A Plant-Animal Symbiosis: Lectin Inhibition Of Reassociation, R. H. Meints, Rosevelt L. Pardy Jan 1980

Quantitative Demonstration Of Cell Surface Involvement In A Plant-Animal Symbiosis: Lectin Inhibition Of Reassociation, R. H. Meints, Rosevelt L. Pardy

School of Biological Sciences: Faculty Publications

The freshwater hydra, Hydra viridis is normally associated with Chlorella-like, algal symbionts which inhabit the host's digestive cells. Under experimental conditions bleached hydra will reassociate with algae harvested from green hydra, but not from our cultures of wild type Chlorella or strain NC64A which when originally isolated from Paramecium bursaria was symbiotically competent. Because of its demonstrated selectivity, the reassociation process is hypothesized to involve a recognition interface whose active participants are the algae cell wall and the digestive cell membrane. The data presented here confirm the hypothesis and suggest some potential molecular characteristics of the interacting partners. Concanavalin …


Absolute Requirement Of Glucocorticoid For Expression Of The Casein Gene In The Presence Of Prolactin, Ranjan Ganguly, Nivedita Ganguly, Nozer M. Mehta, M. R. Banerjee Jan 1980

Absolute Requirement Of Glucocorticoid For Expression Of The Casein Gene In The Presence Of Prolactin, Ranjan Ganguly, Nivedita Ganguly, Nozer M. Mehta, M. R. Banerjee

School of Biological Sciences: Faculty Publications

Second thoracic mammary glands of immature BALB/c female mice were stimulated to pregnancy-like lobuloalveolar (LA) development after 6 days of incubation in a corticosteroid-free step I culture medium containing insulin, prolactin, estradiol, progesterone, and growth hormone. A low basal level (0.0009%) of casein mRNA (mRNAcsn) sequences was detectable in the LA glands by a specific cDNA probe. Subsequent incubation of the LA glands for 3 days in medium containing insulin and prolactin or insulin and cortisol failed to elicit mRNAcsn above the basal level, indicating that neither prolactin nor cortisol alone can support casein gene expression. However, …


Inhibition Of Biological Activity Of Multiplication-Stimulating Activity By Binding To Its Carrier Protein, Daniel J. Knauer, Gary L. Smith Jan 1980

Inhibition Of Biological Activity Of Multiplication-Stimulating Activity By Binding To Its Carrier Protein, Daniel J. Knauer, Gary L. Smith

School of Biological Sciences: Faculty Publications

Multiplication-stimulating activity (MSA) produced by Buffalo rat liver cells (BRL-3A) in culture is related to the somatomedin family of growth regulatory polypeptides. MSA will stimulate glucose transport and DNA synthesis in normal chicken embryo fibroblasts (CIEF) at concentrations of 10-200 ng/ml. MSA found in BRL-3A-conditioned medium, like the somatomedins in serum, does not exist as the free hormone but is' bound to a specific high molecular weight carrier protein. In this report we demonstrate that purified MSA carrier protein (MCP) inhibits the biological activity of MSA on CEF as measured by the stimulation of glucose transport and DNA synthesis. In …


Quantitative Demonstration Of Cell Surface Involvement In A Plant-Animal Symbiosis: Lectin Inhibition Of Reassociation, R. H. Meints, R. L. Pardy Jan 1980

Quantitative Demonstration Of Cell Surface Involvement In A Plant-Animal Symbiosis: Lectin Inhibition Of Reassociation, R. H. Meints, R. L. Pardy

School of Biological Sciences: Faculty Publications

The freshwater hydra, Hydra viridis is normally associated with Chlorella-like, algal symbionts which inhabit the host's digestive cells. Under experimental conditions bleached hydra will reassociate with algae harvested from green hydra, but not from our cultures of wild type Chlorella or strain NC64A which when originally isolated from Paramecium bursaria was symbiotically competent. Because of its demonstrated selectivity, the reassociation process is hypothesized to involve a recognition interface whose active participants are the algae cell wall and the digestive cell membrane. The data presented here confirm the hypothesis and suggest some potential molecular characteristics of the interacting …


Arapaho Prairie, Arthur County, Nebraska: Approximate Ap Grid For Gis, Kathleen H. Keeler, A. T. Harrison, L. S. Vescio Jan 1980

Arapaho Prairie, Arthur County, Nebraska: Approximate Ap Grid For Gis, Kathleen H. Keeler, A. T. Harrison, L. S. Vescio

Harold W. Manter Laboratory of Parasitology: Faculty Publications

Grid map of field sites at Arapaho Prairie in Arthur County, Nebraska. Scale 1 5/16" = 1/4 mile. Shows permanently marked vegetation quadrats, blowouts and ravine washouts, roads, and 100' contour intervals. Part of the map was destroyed by mice. What remains of the map as of 2013 is shown.


Three Proteocephalid Cestodes From Colombian Siluriform Fishes, Including Nomimoscolex Alovarius Sp.N. (Monticelliidae: Z Ygobothriinae), Daniel R. Brooks, Thomas L. Deardorff Jan 1980

Three Proteocephalid Cestodes From Colombian Siluriform Fishes, Including Nomimoscolex Alovarius Sp.N. (Monticelliidae: Z Ygobothriinae), Daniel R. Brooks, Thomas L. Deardorff

Harold W. Manter Laboratory of Parasitology: Faculty Publications

Three species of proteocephalid cestodes were collected from Colombian siluriform fishes. Goezeella siluri Fuhrmann, 1916 is reported from Ageneiosus caucanus for the first time, and Colombia is a new locality. Goezeella siluri has a metascolex, biloculate suckers, and cortical gonads. Proteocephalideans possessing uniloculate suckers and cortical gonads represent two groupings. Those species possessing metascolices represent the genus Spatulifer Woodland, 1934, containing the species surubim, piramutab, piracatinga , rugosa , and rugata. Those lacking metascolices belong in Monticellia LaRue, 1911, comprising coryphicephala, lenha, megacephala, and spinulifera. New combinations include Spatulifer piramutab for Goezeella piramutab, S. piracatinga for Monticellia piracatinga, …


Cestodes In Four Species Of Euryhaline Stingrays From Colombia, Daniel R. Brooks, Monte A. Mayers Jan 1980

Cestodes In Four Species Of Euryhaline Stingrays From Colombia, Daniel R. Brooks, Monte A. Mayers

Harold W. Manter Laboratory of Parasitology: Faculty Publications

Seven species of cestodes are reported from coastal stingrays in the vicinity of Cartagena, Colombia, Acanthobothrium colombianum sp,n. from Aetobatis narinari resembles A . paulum and A. mathiasi but differs by having relatively shorter, more squared proglottids at the end of the strobila, a pre-equatorial genital pore, relatively less elongate ovarian lobes in terminal proglottids, and less prominent apical suckers and pads. Acanthobothrium urotrygoni sp.n. from Urotrygon venezuelae most closely resembles A . olseni in bothridial hook length but differs in cirrus sac size, resembles A. southwelli in cirrus sac size but differs in bothridial hook length, and differs from …


Taxonomy And Biology Of North American Species Of Goezia (Nematoda: Anisakidae) From Fishes, Including Three New Species, Thomas L. Deardorff, Robin M. Overstreet Jan 1980

Taxonomy And Biology Of North American Species Of Goezia (Nematoda: Anisakidae) From Fishes, Including Three New Species, Thomas L. Deardorff, Robin M. Overstreet

Harold W. Manter Laboratory of Parasitology: Faculty Publications

Three new species of Goezia from fishes in North America are described and supplemental data for G. minuta and several unidentified adults and larvae are presented. Males, especially their caudal papillae, are necessary to identify most species. For the new species, G. pelagia sp. n. from Rachycentron canadum and Chaetodipterus faber in the northern Gulf of Mexico possesses 12- 19 preanal, two para-anal, and four postanal pairs of papillae; G. kliksi sp. n. from Pogonias cromis in Lake Borgne, Louisiana, has 10-16 preanal, two para-anal, and five postanal pairs of papillae, and G. sinamora sp. n. from Tilapia aurea, …


Two New Species Of Cestode (Trypanorhyncha, Eutetrarhynchidae) From The Yellow-Spotted Stingray, Urolophus Jamaicensis, Kinga J. Kovacs, Gerald D. Schmidt Jan 1980

Two New Species Of Cestode (Trypanorhyncha, Eutetrarhynchidae) From The Yellow-Spotted Stingray, Urolophus Jamaicensis, Kinga J. Kovacs, Gerald D. Schmidt

Harold W. Manter Laboratory of Parasitology: Faculty Publications

Eutetrarhynchus thalassius sp.n. and Eutetrarhynchus caribbensis sp.n. were collected from the spiral valves of three yellow-spotted stingrays, Urolophus jamaicensis, in Discovery Bay, Jamaica. Both species most closely resemble Eutetrarhynchus geraschmidti Dollfus, 1974. Eutetrarhynchus thalassius differs from E. geraschmidti in the arrangement, sizes, and shapes of tentacular armature, Eutetrarhynchus caribbensis differs from E. geraschmidti and E. thalassius on the basis of metabasal armature. The tentacular armature of E. geraschmidti is redescribed,


Cestode Parasites Of Some Venezuelan Stingrays, Monte A. Mayes, Daniel R. Brooks Jan 1980

Cestode Parasites Of Some Venezuelan Stingrays, Monte A. Mayes, Daniel R. Brooks

Harold W. Manter Laboratory of Parasitology: Faculty Publications

Forty-seven stingrays representing 8 species collected in Venezuelan coastal waters were examined for cestode parasites. Specimens of 18 tetraphyllidean, lecanicephalidean, and trypanorhynchan cestode species were collected, 3 described as new. Rhinebothrium margaritense sp. n. from Dasyatis guttata and D. americana most closely resembles R. spinicephalum and R. tetralobatum but differs by having 3-6 rather than only 2 testes per proglottid and a different number of bothridial loculi. Rhodobothrium paucitesticulare sp. n. from Rhinoptera bonasus possesses fewer than half as many testes per proglottid as any other known member of the genus. Dioecotaenia campbelli sp. n. differs from D. cancellata by …


Apparent Chromosomal Heterosis In A Fossorial Mammal, John C. Patton, Robert J. Baker, Hugh H. Genoways Jan 1980

Apparent Chromosomal Heterosis In A Fossorial Mammal, John C. Patton, Robert J. Baker, Hugh H. Genoways

University of Nebraska State Museum: Mammalogy Papers

For the past decade, numerous investigators have attempted to explain the plethora of genetic polymorphism found in nature (see Ayala 1976). However, few researchers have been able to document how polymorphisms have been maintained, whether the polymorphisms were genic or chromosomal. Our investigations into the maintenance of a Robertsonian chromosomal polymorphism in the plains pocket goher, Geomys bursarius major, have revealed evidence that this polymorphism is maintained by differential viabilities of the three chromosomal morphs, with the heterozygote being favored.


Phytoplankton Studies Within The Virginia Barrier Islands I. Seasonal Study Of Phytoplankton In Goose Lake, Parramore Island, Harold G. Marshall Jan 1980

Phytoplankton Studies Within The Virginia Barrier Islands I. Seasonal Study Of Phytoplankton In Goose Lake, Parramore Island, Harold G. Marshall

Biological Sciences Faculty Publications

The phytoplankton of Goose Lake, an oligohaline lake on Parramore Island, was studied for one year. The populations consisted primarily of ultraplankton and nanoplankton-sized forms with diatoms and chlorophyceans dominant most of the year. A general pattern of seasonally higher cell concentrations in early summer and fall was noted, with an unidentified ultraplankton-sized component prominent throughout the collection period. A list of 154 species is given.


A Guide To The Threatened And Endangered Vascular Plants Of The Lake Mead National Recreation Area, James S. Holland, Wesley E. Niles, Charles L. Douglas, Dennis R. Schramm Jan 1980

A Guide To The Threatened And Endangered Vascular Plants Of The Lake Mead National Recreation Area, James S. Holland, Wesley E. Niles, Charles L. Douglas, Dennis R. Schramm

Publications (WR)

This illustrated guide was prepared to provide the botanical community, land managers, and other interested persons with a reference that describes and locates the twelve plant taxa currently being considered by the Fish and Wildlife Service for threatened or endangered status in or around the Lake Mead National Recreation Area. The guide is intended to assist managers of government agencies in determining the presence of these species and in defining management programs for their protection. The guide should be consulted prior to any construction project. If a potential conflict is identified, an onsite evaluation should be conducted early in the …