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Naturalization Of Sequoiadendron Giganteum (Cupressaceae) In Montane Southern California, Rudolf Schmid, Mena Schmid Sep 2012

Naturalization Of Sequoiadendron Giganteum (Cupressaceae) In Montane Southern California, Rudolf Schmid, Mena Schmid

Aliso: A Journal of Systematic and Floristic Botany

After the August 1974 fire in the upper Hall Canyon area on the southwestern flank of Black Mountain in the northwestern San Jacinto Mountains, Riverside County, California, the United States Forest Service revegetated the burn in the mixed-conifer forest with the Sierra Nevada endemic Sequoiadendron giganteum (Cupressaceae). On 1 May 2009 a GPS census starting at the head of Hall Canyon revealed both in the canyon and upslope beyond it at least 157 individuals in the vicinity of the Black Mountain Trail, plus an outlier 450 m distant near the summit. This species alien to southern California is regenerating prolifically …


Five New Records Of Ants (Hymenoptera: Formicidae) For Nebraska, Kristine T. Nemec, James C. Trager, Elizabeth Manley, Craig R. Allen Jun 2012

Five New Records Of Ants (Hymenoptera: Formicidae) For Nebraska, Kristine T. Nemec, James C. Trager, Elizabeth Manley, Craig R. Allen

The Prairie Naturalist

Ants are ubiquitous and influential organisms in terrestrial ecosystems. About 1,000 ant species occur in North America, where they are found in nearly every habitat (Fisher and Cover 2007). Ants are critical to ecological processes and structure. Ants affect soils via tunneling activity (Baxter and Hole 1967), disperse plant seeds (Lengyel et al. 2009), prey upon a variety of insects and other invertebrates (Way and Khoo 1992, Folgarait 1998), are often effective primary consumers through their prodigious consumption of floral and especially extrafloral nectar, and honeydew (Tobin 1994), and serve as prey for invertebrates (Gotelli 1996, Gastreich 1999) and vertebrates …


Spatial Ecology Of Urban Raccoons In Northeastern Ohio: Implications For Oral Rabies Vaccination, Are R. Berentsen, Mike R. Dunbar, Chadd E. Fitzpatrick, W. David Walter Jun 2012

Spatial Ecology Of Urban Raccoons In Northeastern Ohio: Implications For Oral Rabies Vaccination, Are R. Berentsen, Mike R. Dunbar, Chadd E. Fitzpatrick, W. David Walter

The Prairie Naturalist

In 1977, rabies was detected in a raccoon (Procyon lotor) in West Virginia, and since the mid-1980s raccoon variant rabies has spread throughout the eastern United States and moved west as far as the eastern edge of Cleveland, Ohio. The primary tool to combat this spread is the distribution of oral rabies vaccine (ORV) baits. A thorough knowledge of raccoon space use is critical in determining bait placement, particularly in urban areas. We monitored nine raccoons in urban areas of Cleveland, Ohio, calculated home range sizes, monitored raccoon movement with respect to potential movement barriers, and used resource selection functions …


Reproductive Biology Of Ludwigia Leptocarpa And L. Adscendens Subsp. Diffusa In Ile Ife, Nigeria, Matthew Oziegbe, Julius Olaoye Faluyi Jan 2012

Reproductive Biology Of Ludwigia Leptocarpa And L. Adscendens Subsp. Diffusa In Ile Ife, Nigeria, Matthew Oziegbe, Julius Olaoye Faluyi

Turkish Journal of Botany

Ludwigia L. (Onagraceae) species are known to be invasive in most parts of the world, serving as a threat to native plant species and blocking navigational channels. In Africa, they block waterways and are serious weeds in wet fields, most especially in rice paddies. The floral morphology, mode of sexual reproduction, and mechanism of fruit dispersal in water of L. leptocarpa (Nutt.) H.Hara and L. adscendens (L.) H.Hara subsp. diffusa (Forssk.) P.H.Raven were assessed in the Department of Botany of Obafemi Awolowo University, Ile Ife, Nigeria, from March 2006 to March 2009. L. leptocarpa produced cylindrical, hairy fruits of 34.80 …


In Vitro Plant Regeneration Via Petiole Callus Of Viola Patrinii And Genetic Fidelity Assessment Using Rapd Markers, Gururaj Chalageri, Uddagiri Venkanna Babu Jan 2012

In Vitro Plant Regeneration Via Petiole Callus Of Viola Patrinii And Genetic Fidelity Assessment Using Rapd Markers, Gururaj Chalageri, Uddagiri Venkanna Babu

Turkish Journal of Botany

Viola patrinii DC. (Violaceae) petiole explants were used for inducing calli. Significant callus proliferation was observed on MS medium supplemented with 16.12 \muM NAA and 13.33 \muM BA. Shoot regeneration was achieved upon transferring the green friable calli to MS medium with a 2-fold dilution of potassium dihydrogen phosphate supplemented with 23.25 \muM Kn and 2.68 \muM NAA. Maximum shoot regeneration was achieved in 4 weeks. Multiple shoots were separated and further cultured in half-strength MS medium supplemented with 9.85 \muM IBA with 2% sucrose. Profuse root development was observed after 20-25 days of culturing. Regenerated plants were successfully transferred …


Anatomical Analysis Of Red Juniper Leaf (Juniperus Oxycedrus) Taken From Kopaonik Mountain, Serbia, Predrag Spasoje Vasic, Darko Vlajko Dubak Jan 2012

Anatomical Analysis Of Red Juniper Leaf (Juniperus Oxycedrus) Taken From Kopaonik Mountain, Serbia, Predrag Spasoje Vasic, Darko Vlajko Dubak

Turkish Journal of Botany

In this study, the anatomical characteristics of Juniperus oxycedrus (Cupressaceae) leaves from Kopaonik Mountain (Serbia) are analysed. The level of distinction between leaves taken from various altitudes (420-1420 m) was determined by analysing anatomical characters. The clear correlation between increase in altitude and change in anatomical characters of the leaves was not established by descriptive analysis. The leaves collected from plants growing at 620 m had the most prominent xeromorphic characteristics (thick cuticles and thick epidermis walls). The discriminant canonical analysis also showed a clear distinction between red common juniper from 420 m and the samples taken from different altitudes.


Seasonal Variations In Phytoplankton Communities In Zayandeh-Rood Dam Lake (Isfahan, Iran), Masoumeh Shams, Saeed Afsharzadeh, Tahi̇r Atici Jan 2012

Seasonal Variations In Phytoplankton Communities In Zayandeh-Rood Dam Lake (Isfahan, Iran), Masoumeh Shams, Saeed Afsharzadeh, Tahi̇r Atici

Turkish Journal of Botany

Variations in the phytoplankton of Zayandeh-Rood Dam Lake were studied seasonally from September 2005 to August 2006 at 4 different stations. A total of 112 species and 53 genera belonging to 6 divisions were identified. The species belonging to Bacillariophyta, Chlorophyta, Cyanophyta, Euglenophyta, and Dinophyta were found frequently. Chrysophyta species were found in low numbers. Cyclotella meneghinina Kütz., a centric diatom, was the dominant species at all stations. The density of the phytoplankton was between 470 and 150,470 cells/cm^3. According to the Shannon-Weaver Index, the highest and the lowest diversities were determined in November and May, respectively. Regarding physico-chemical analysis …


Survey Of The Native And Nonnative Vascular Plant Species Of Three Islands In Lake Winnipesaukee, New Hampshire, Mark Gardner Winkler Jan 2012

Survey Of The Native And Nonnative Vascular Plant Species Of Three Islands In Lake Winnipesaukee, New Hampshire, Mark Gardner Winkler

Electronic Theses and Dissertations

This study examined the long-term patterns in vascular plant composition on three islands in Lake Winnipesaukee, NH. It also tested the role of island biogeography in ecology as it analyzed the effectiveness of a land use plan implemented on the islands. Samplings were made on the islands in the summer of 2011 and were compared to earlier samplings in 1978, 1991, and 2001. The flora was observed and measured in 25 permanent plots that were established on the three islands in 1978. The understory flora was measured by presence and percent cover and the overstory was measured by frequency and …


Genetic Structure Of Grass Carp Populations In The Missouri And Mississippi River Basins, Usa, Bobbi M. Adams, Katie N. Bertrand, Michael L. Brown, Donald Auger Dec 2011

Genetic Structure Of Grass Carp Populations In The Missouri And Mississippi River Basins, Usa, Bobbi M. Adams, Katie N. Bertrand, Michael L. Brown, Donald Auger

The Prairie Naturalist

We provided an early characterization of the genetic structure of the grass carp (Ctenopharyngodon idella) population as it expands its distribution in both the Missouri and Mississippi River basins. Further, we provided initial comparisons of allelic richness at 17 polymorphic microsatellite markers between 56 grass carp from the USA, and six from the Yangtze River in China. The number of alleles per locus ranged from two to eight and size ranges of alleles for fish collected from the invaded and native ranges were similar (P ≤ 0.001; 107–226 bp) to those previously reported in the literature. Distance-based clustering …


Phragmites Australis In South Dakota: Historical Distribution And Environment, Carol A. Johnston, Kayla L. Miller Jun 2011

Phragmites Australis In South Dakota: Historical Distribution And Environment, Carol A. Johnston, Kayla L. Miller

The Prairie Naturalist

Common reed, Phragmites australis, has long been a component of Northern Plains wetlands, but impending invasion by the non-native P. australis haplotype M may displace native haplotypes in the future. To increase understanding of historical Phragmites occurrence, we developed a geographic information system (GIS) protocol to improve the georeferencing of specimens from South Dakota herbaria, and mapped the distribution of Phragmites relative to geology, physiographic regions, and water bodies. There were 91 Phragmites herbarium specimens from South Dakota and adjacent Wyoming. Phragmites collections occurred in nearly all physiographic regions of the state, with concentrations occurring in the Prairie Coteau of …


Habitat Selection By Female Swift Foxes (Vulpes Velox) During The Pup- Rearing Season, Indrani Sasmal, Jonathan A. Jenks, Troy W. Grovenburg, Shubham Datta, Greg. M. Schroeder, Robert W. Klaver, Kevin M. Honness Jun 2011

Habitat Selection By Female Swift Foxes (Vulpes Velox) During The Pup- Rearing Season, Indrani Sasmal, Jonathan A. Jenks, Troy W. Grovenburg, Shubham Datta, Greg. M. Schroeder, Robert W. Klaver, Kevin M. Honness

The Prairie Naturalist

The swift fox (Vulpes velox) was historically distributed in western South Dakota including the region surrounding Badlands National Park (BNP). The species declined during the mid-1800s, largely due to habitat loss and poisoning targeted at wolves (Canis lupis) and coyotes (C. latrans). Only a small population of swift foxes near Ardmore, South Dakota persisted. In 2003, an introduction program was initiated at BNP with swift foxes translocated from Colorado and Wyoming. We report on habitat use by female swift foxes during the pup-rearing season (May–July) in 2009. Analyses of location data from 13 radiomarked female foxes indicated disproportional use (P < 0.001) of some habitats relative to their availability within swift fox home ranges. Swift foxes used grassland (ŵ = 1.01), sparse vegetation (ŵ = 1.43) and prairie dog towns (ŵ = 1.18) in proportion to their availability, whereas they were less likely to use woodland (ŵ = 0.00), shrubland (ŵ = 0.14), pasture/agricultural-land (ŵ = 0.25) and development (ŵ = 0.16) relative to availability. Swift foxes typically are located in habitats that provide greater visibility, such as shortgrass prairie and areas with sparse vegetation; which allow detection of approaching coyotes (e.g., primary predator of swift foxes).


Distribution Of Crayfish Species In Select North Dakota Streams, Cari-Ann Hayer, Terrance L. Velazquez, Mclain S. Johnson, Brian Graeb Jun 2011

Distribution Of Crayfish Species In Select North Dakota Streams, Cari-Ann Hayer, Terrance L. Velazquez, Mclain S. Johnson, Brian Graeb

The Prairie Naturalist

Crayfish have an integral role in aquatic ecosystems, serving as herbivores, predators, detritivores, and prey for fishes and other aquatic and terrestrial animals (Momot 1995, Taylor et al. 1996, Martin 1997). Many crayfish populations are currently declining as a result of habitat alteration (Taylor et al. 1996) and invasive predators (e.g., rusty crayfish Orconectes rusticus [Girard; Lodge et al. 2000]). Knowledge of crayfish distribution and biology in North America and specifically North Dakota is sparse or lacking (Taylor et al. 1996) and baseline information is necessary to identify effects of anthropogenic alterations. Early inventories documented 3 crayfish species in North …


Summaries Of Arkansas Cotton Research 2010, Derrick M. Oosterhuis May 2011

Summaries Of Arkansas Cotton Research 2010, Derrick M. Oosterhuis

Arkansas Agricultural Experiment Station Research Series

No abstract provided.


A Comparative Assessment Of Fruit Formation In Some Orchid Species From The Southern Caucasus Region, Houshang Nosrati, Roghieh Hajiboland, Ahmad Razban-Haghighi, Maryam Nikniazi Jan 2011

A Comparative Assessment Of Fruit Formation In Some Orchid Species From The Southern Caucasus Region, Houshang Nosrati, Roghieh Hajiboland, Ahmad Razban-Haghighi, Maryam Nikniazi

Turkish Journal of Botany

The distribution and population size of 5 orchid species (Cephalanthera longifolia, Orchis simia, Platanthera bifolia, Dactylorhiza romana, and Ophrys scolopax) were studied in the southern Caucasus based on the individual numbers in a given area. The fruit set was recorded for the latter 3 species and compared in natural and control groups (pollinators prevented) for D. romana and O. scolopax. We compared the obtained fruit set values with those reported from other regions. The distributions of the 5 species were completely fragmented and the population sizes were extremely small. This is the first report of O. scolopax from the region, …


Interisland Variability Of Dune Plant Community Structure On Virginia's Barrier Islands, Justin K. Shafer Apr 2010

Interisland Variability Of Dune Plant Community Structure On Virginia's Barrier Islands, Justin K. Shafer

Biological Sciences Theses & Dissertations

The barrier islands of the Virginia Coast Reserve LTER site provide an opportunity to study interisland variability of dune plant communities. My research focused on the variation in biomass and diversity of communities among islands and dune positions. Grassy dunes of young, intermediate and old age were sampled on Smith, Hog, and Parramore Islands. Aboveground biomass was obtained from harvest plots, and roots were extracted from cores. Data were collected on depth to groundwater and total soil nitrogen. Variation in mean aboveground biomass was evident among the islands with the highest values on Hog Island, followed by Smith, then Parramore …


Combining Local- And Large-Scale Models To Predict The Distributions Of Invasive Plant Species, Chad C. Jones, Steven A. Acker, Charles B. Halpern Mar 2010

Combining Local- And Large-Scale Models To Predict The Distributions Of Invasive Plant Species, Chad C. Jones, Steven A. Acker, Charles B. Halpern

Botany Faculty Publications

Habitat-distribution models are increasingly used to predict the potential distributions of invasive species and to inform monitoring. However, these models assume that species are in equilibrium with the environment, which is clearly not true for most invasive species. Although this assumption is frequently acknowledged, solutions have not been adequately addressed. There are several potential methods for improving habitat-distribution models. Models that require only presence data may be more effective for invasive species, but this assumption has rarely been tested. In addition, combining modeling types to form ‘ensemble’ models may improve the accuracy of predictions. However, even with these improvements, models …


Phylogenetic Relationships Of Some Turkish Crocus (Iridaceae) Taxa Based On Morphological And Anatomical Characters, Fati̇h Coşkun, Selami̇ Selvi̇, Fati̇h Satil Jan 2010

Phylogenetic Relationships Of Some Turkish Crocus (Iridaceae) Taxa Based On Morphological And Anatomical Characters, Fati̇h Coşkun, Selami̇ Selvi̇, Fati̇h Satil

Turkish Journal of Botany

In this study, relationships among the 15 taxa of the genus Crocus L. distributed in Turkey were analysed using 29 morphological and 4 anatomical characters. Analysis of the data set utilising maximum parsimony criterion with Branch-and-Bound search algorithm yielded 32 most parsimonious trees. Bootstrap analysis with the majority rule consensus algorithm generated a consensus tree supporting some branches. Our data mostly did not agree with the previous sectional and serial treatments. The most interesting result was the condition of Crocus pallasii, which was previously included in the section Crocus. C. pallasii showed a sister group relationship with C. cancellatus from …


Carbon Dynamics In A Phragmites Australis Invaded Riparian Wetland, Steven Walters Jan 2010

Carbon Dynamics In A Phragmites Australis Invaded Riparian Wetland, Steven Walters

School of Natural Resources: Dissertations, Theses, and Student Research

Invasive plant species are widely recognized as a major threat to biodiversity and ecosystem stability. Wetland ecosystems tend to be much more susceptible to invasions because of their location on the landscape where water, nutrients, and the impacts of disturbances accumulate. Invasive plants have the ability to alter ecosystem processes and community/population dynamics. The ability of invasive plants to alter these processes can have profound economic consequences. In the United States, control of invasive wetland species alone costs approximately 155 million dollars annually. The state of Nebraska spends 2 million dollars annually controlling invasive plant species in the Platte River …


Effects Of Moist Chilling, Gibberellic Acid, And Scarification On Seed Dormancy In The Rare Endemic Pedicularis Olympica (Scrophulariaceae), Serap Kirmizi, Gürcan Güleryüz, Hülya Arslan, Fatma Selcen Sakar Jan 2010

Effects Of Moist Chilling, Gibberellic Acid, And Scarification On Seed Dormancy In The Rare Endemic Pedicularis Olympica (Scrophulariaceae), Serap Kirmizi, Gürcan Güleryüz, Hülya Arslan, Fatma Selcen Sakar

Turkish Journal of Botany

We investigated the germination requirements of a rare endemic plant species, Pedicularis olympica Boiss. (Scrophulariaceae), which grows in wet habitats on Uludağ Mountain, Turkey. We studied the effects of scarification, moist chilling (+4 °C) for 15 days, different doses of gibberellic acid (GA_{3}; 100, 150, and 250 ppm) and combined hormone and moist chilling treatments under dark (20 °C) and photoperiod (20/10 °C; 12/12 h, respectively) conditions. GA_{3} was able to break dormancy. The highest germination rate was found in the seeds treated with 250 ppm GA_{3}; 64% of these seeds germinated when treated with moist chilling and incubated in …


Phylogeny, Adaptive Radiation, And Historical Biogeography In Bromeliaceae: Insights From An Eight-Locus Plastid Phylogeny, Thomas J. Givnish, Michael H. J. Barfuss, Benjamin Van Ee, Ricarda Riina, Katharina Schulte, Ralf Horres, Philip A. Gonsiska, Rachel S. Jabaily, Darren M. Crayn, J. Andrew Smith Jan 2009

Phylogeny, Adaptive Radiation, And Historical Biogeography In Bromeliaceae: Insights From An Eight-Locus Plastid Phylogeny, Thomas J. Givnish, Michael H. J. Barfuss, Benjamin Van Ee, Ricarda Riina, Katharina Schulte, Ralf Horres, Philip A. Gonsiska, Rachel S. Jabaily, Darren M. Crayn, J. Andrew Smith

Biological Sciences Faculty Publications

Premise: Bromeliaceae form a large, ecologically diverse family of angiosperms native to the New World. We use a bromeliad phylogeny based on eight plastid regions to analyze relationships within the family, test a new, eight-subfamily classification, infer the chronology of bromeliad evolution and invasion of different regions, and provide the basis for future analyses of trait evolution and rates of diversification.

Methods: We employed maximum-parsimony, maximum-likelihood, and Bayesian approaches to analyze 9341 aligned bases for four outgroups and 90 bromeliad species representing 46 of 58 described genera. We calibrate the resulting phylogeny against time using penalized likelihood applied …


The Prairie Naturalist. Volume 40, No. 3/4 September/December 2008, The Great Plains Natural Science Society Sep 2008

The Prairie Naturalist. Volume 40, No. 3/4 September/December 2008, The Great Plains Natural Science Society

The Prairie Naturalist

WINTERKILL AND BIOMASS OF THE PAINTED TURTLE IN A SOUTH DAKOTA WETLAND. S. G. Platt, Z. Fast Horse, W. Cross, S. Mannel, and T. R. Rainwater

NON-BLACKBIRD AVIAN OCCURRENCE AND ABUNDANCE IN NORTH DAKOTA SUNFLOWER FIELDS. O. A. Schaaf, G. M. Linz, C. Ooetkott, M. W. Lutman, and W. J. Bleier

USING LOCAL KNOWLEDGE AND REMOTE SENSING TO MAP KNOWN AND POTENTIAL PRAIRIE-CHICKEN DISTRIBUTION IN KANSAS. M. E. Houts, R. O. Rodgers, R. D. Applegate, and W. H. Busby

A CASE STUDY OF A SUCCESSFUL LAKE REHABILITATION PROJECT IN SOUTH-CENTRAL NEBRASKA. P. J. Spirk, B. A. Newcomb, and K. O. …


Non-Blackbird Avian Occurrence And Abundance In North Dakota Sunflower Fields, Dionn A. Schaaf, George M. Linz, Curt Doetkott, Mark W. Lutman, William J. Bleier Sep 2008

Non-Blackbird Avian Occurrence And Abundance In North Dakota Sunflower Fields, Dionn A. Schaaf, George M. Linz, Curt Doetkott, Mark W. Lutman, William J. Bleier

The Prairie Naturalist

Sunflower fields are well-documented as foraging habitat for fallmigrating blackbirds (Family Icteridae). There is, however, a paucity of information on the use of sunflower fields by non-blackbirds. We assessed non-blackbird use of 12 ripening sunflower fields in the Prairie Pothole Region of central North Dakota. From mid-August to mid-October 2000, we counted 4,129 individual birds, consisting of 22 families and 61 species, in the sample fields and within 5 m of the field edges. We saw the largest number of birds from 18 September to 27 September. The Family Emberizidae (sparrows) accounted for 26% of the species and 20% of …


Winterkill And Biomass Of The Painted Turtle In A South Dakota Wetland, Steven G. Platt, Zannita Fast Horse, Warren Cross, Sylvio Mannel, Thomas R. Rainwater Sep 2008

Winterkill And Biomass Of The Painted Turtle In A South Dakota Wetland, Steven G. Platt, Zannita Fast Horse, Warren Cross, Sylvio Mannel, Thomas R. Rainwater

The Prairie Naturalist

Winterkill occurs when drought conditions expose hibernating turtles to desiccation and lethaly cold temperatures. Winterkill is thought to represent a major source of mortality in northern populations of the painted turtle (Chrysemys picta), but few field observations are available. We herein reported on catastrophic winterkill among western painted turtle (C. pieta bellii) at Limestone Butte Lake (LBL) in western South Dakota during the winter of 2003-2004. Additionally, we used the carcasses of winterkilled turtles (n = 86) to estimate the standing crop biomass of the painted turtle at LBL (0.6 kg/ha). This was the only estimate …


Use Of Passive Integrated Transponders In Hatchling Texas Horned Lizards, Scott E. Henke Jan 2008

Use Of Passive Integrated Transponders In Hatchling Texas Horned Lizards, Scott E. Henke

The Prairie Naturalist

The Texas horned lizard (Phrynosoma cornutum) is a Texas state-threatened species and acquisition of data related to the species' ecology is essential. To accomplish this task individual animals need to be marked. Many marking techniques are available for lizards, however the majority of techniques have been tested on adults only. Studies involving hatchling and juvenile horned lizards are scarce due to problems associated with marking and relocating individuals in these age classes. I demonstrated that injection of passive integrated transponders (PIT's) can safely be used as a marking method in young Texas horned lizards. Thirty-two captive bred hatchling lizards were …


Phenotypic Plasticity Of Reproduction In Schizachyrium Scoparium (Poaceae) Populations In Relation To Ecological History, Elizabeth M. Obee, James A. Quinn Dec 2007

Phenotypic Plasticity Of Reproduction In Schizachyrium Scoparium (Poaceae) Populations In Relation To Ecological History, Elizabeth M. Obee, James A. Quinn

Aliso: A Journal of Systematic and Floristic Botany

Genetic differentiation in reproduction in the wide-ranging Schizachyrium scoparium (Poaceae) has been demonstrated in uniform gardens. However, the fine-tuning of flowering phenology and biomass allocation in relation to spatial and temporal fluctuations in the local environment is best accomplished by plastic responses to local variability. An earlier central New Jersey study suggested that S. scoparium populations in old fields of 2 to 40 years differed in plasticity. To test this apparent effect of ecological history on the development of different levels of plasticity, genotypes were collected from high- and low-fertility sites in New Jersey (forest biome) and in Oklahoma (grassland …


Homestead National Monument Of America Bur Oak Forest Restoration Plan: Reference Condition And Management Considerations, Steven B. Rolfsmeier Jan 2007

Homestead National Monument Of America Bur Oak Forest Restoration Plan: Reference Condition And Management Considerations, Steven B. Rolfsmeier

Nebraska Game and Parks Commission: White Papers, Conference Presentations, and Manuscripts

The Vegetation Management Action Plan for Homestead National Monument of America includes a statement of the desired future condition that states: "The monument's natural resources are managed in such a way as to maintain a heterogeneous landscape composed of a mosaic of high quality remnant and restored tallgrass prairie, lowland bur oak forest and associated ecotones, as well as prairie streams and their hydrologic processes; that reflects the value of the site as a homestead, represents as accurately as possible the environment encountered by early settlers, and preserves native biodiversity" (Bolli 2006). The lowland bur oak forest along Cub Creek …


The Function Of Stilt Roots In The Growth Strategy Of Socratea Exorrhiza (Arecaceae) At Two Neotropical Sites, Gregory R. Goldsmith, Rakan A. Zahawi Jan 2007

The Function Of Stilt Roots In The Growth Strategy Of Socratea Exorrhiza (Arecaceae) At Two Neotropical Sites, Gregory R. Goldsmith, Rakan A. Zahawi

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Arboreal palms have developed a variety of structural root modifications and systems to adapt to the harsh abiotic conditions of tropical rain forests. Stilt roots have been proposed to serve a number of functions including the facilitation of rapid vertical growth to the canopy and enhanced mechanical stability. To examine whether stilt roots provide these functions, we compared stilt root characteristics of the neotropical palm tree Socratea exorrhiza on sloped ( > 20°) and flat locations at two lowland neotropical sites. S. exorrhiza (n=80 trees) did not demonstrate differences in number of roots, vertical stilt root height, root cone circumference, root …


Further Evidence For Seed Size Variation In The Genus Zostera: Exploratory Studies With Z. Japonica And Z. Asiatica, Sandy Wyllie-Echeverria, Victoria R. Wyllie-Echeverria, Algernon C. Churchill, Paul A. Cox Jan 2006

Further Evidence For Seed Size Variation In The Genus Zostera: Exploratory Studies With Z. Japonica And Z. Asiatica, Sandy Wyllie-Echeverria, Victoria R. Wyllie-Echeverria, Algernon C. Churchill, Paul A. Cox

Aliso: A Journal of Systematic and Floristic Botany

Recent studies found seed size variation within the seagrass Zostera marina, one of nine species in the genus Zostera. The objectives of this study were to determine if variation also exists in the seeds of two other species Zostera japonica and Zostera asiatica within this genus. Results indicate that: (1) length and weight varied between two populations (one indigenous population from Akkeshi-Ko, Japan, and one exotic population from Willapa Bay, Washington, USA) of the small-bodied intertidal seagrass species Z. japonica, and (2) seed-size classes were discernable. Preliminary investigations were also initiated with a Japanese population of Z. asiatica …


Speciation In Duckweeds (Lemnaceae): Phylogenetic And Ecological Inferences, Daniel J. Crawford, Elias Landolt, Donald H. Les, Rebecca T. Kimball Jan 2006

Speciation In Duckweeds (Lemnaceae): Phylogenetic And Ecological Inferences, Daniel J. Crawford, Elias Landolt, Donald H. Les, Rebecca T. Kimball

Aliso: A Journal of Systematic and Floristic Botany

Species of duckweeds (Letnnaceae) that were resolved as sister taxa in a phylogeny based on combined molecular and non-molecular data were compared for morphological, physiological, and ecological attributes to infer factors important in the initial divergence leading to speciation. The ability to survive extreme conditions such as desiccation and cold temperatures is the most common difference identified between species. Two morphological characters facilitating survival in extreme environments are production of special resting buds called turions and increased seed production. The prevalent geographic pattern for species pairs consists of one restricted species occurring on the periphery of a more widespread taxon; …


Bloodroot Pollination: Bet-Hedging In Uncertain Times, W. John Hayden Feb 2005

Bloodroot Pollination: Bet-Hedging In Uncertain Times, W. John Hayden

Biology Faculty Publications

“Hurry up and wait.” The phrase that epitomizes life in the military or any other large, bureaucratic, organization, applies surprisingly well to bloodroot and similar ephemeral wildflowers. Each year these plants race to flower as early as possible to assure sufficient time for fruits to ripen and seeds to mature while sunshine is abundant at the forest floor, for all too soon the forest floor will be draped in shadows cast by the trees’ leafy canopy. Ephemerals do everything quickly: sprout, grow, flower, disperse seeds, and re-enter dormancy. But flowering in very early spring can be risky. Some days will …