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Two-Dimensional Hydraulic Modeling Approach To Linking Stream Morphology And Aquatic Habitat Quality, J. S. Clark, W. C. Hession, Donna M. Rizzo, J. P. Laible, M. C. Watzin Jul 2006

Two-Dimensional Hydraulic Modeling Approach To Linking Stream Morphology And Aquatic Habitat Quality, J. S. Clark, W. C. Hession, Donna M. Rizzo, J. P. Laible, M. C. Watzin

International Congress on Environmental Modelling and Software

A two-dimensional hydrodynamic model (River2D) was utilized to evaluate the relationship between geomorphic condition (as estimated using an existing rapid assessment protocol) and instream habitat quality in small Vermont streams. Six stream reaches ranging in geomorphic condition from good to poor according to the protocols were utilized for this study. We conducted detailed topographic surveys, quantified bed substrate, and measured velocity values during baseflow conditions. The reach models were calibrated with realistic roughness values based on field observations and pebble counts. After calibration, the flows were scaled up to median and bankfull flows for additional analysis. The weighted usable area …

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Preparing More Effective Liquid State Machines Using Hebbian Learning, David Norton, Dan A. Ventura Jul 2006

Preparing More Effective Liquid State Machines Using Hebbian Learning, David Norton, Dan A. Ventura

Faculty Publications

In Liquid State Machines, separation is a critical attribute of the liquid—which is traditionally not trained. The effects of using Hebbian learning in the liquid to improve separation are investigated in this paper. When presented with random input, Hebbian learning does not dramatically change separation. However, Hebbian learning does improve separation when presented with real-world speech data.

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Spatiotemporal Pattern Recognition Via Liquid State Machines, Eric Goodman, Dan A. Ventura Jul 2006

Spatiotemporal Pattern Recognition Via Liquid State Machines, Eric Goodman, Dan A. Ventura

Faculty Publications

The applicability of complex networks of spiking neurons as a general purpose machine learning technique remains open. Building on previous work using macroscopic exploration of the parameter space of an (artificial) neural microcircuit, we investigate the possibility of using a liquid state machine to solve two real-world problems: stockpile surveillance signal alignment and spoken phoneme recognition.

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Model Studies Towards The Total Synthesis Of Lyconadin A Via An Acyl Radical Cascade Reaction, Koudi Zhu Jun 2006

Model Studies Towards The Total Synthesis Of Lyconadin A Via An Acyl Radical Cascade Reaction, Koudi Zhu

Theses and Dissertations

Lyconadin A is an alkaloid possessing a unique structure and antitumor activity. The total synthesis of Lyconadin A was proposed via an acyl radical cascade reaction. To investigate the possibility and stereoselectivity of the cascade cyclization, phenyl selenoester 16 was chosen as a model substrate to study the 7-exo-5-exo radical cyclization. A synthetic route to phenyl selenoester 16 was developed. The 7-exo-5-exo radical cyclization was found to occur with a high yield and excellent stereoselectivty. Attempts were also tried to synthesize another radical precursor 14 albeit with less success. A synthetic pathway to the synthesis of 14 as well as …

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Properties Of Conductance And Inhibition Of Proton Channels: M2 From Influenza A Virus And Fo From Escherichia Coli Atp Synthase, Jeffrey C. Moffat Jun 2006

Properties Of Conductance And Inhibition Of Proton Channels: M2 From Influenza A Virus And Fo From Escherichia Coli Atp Synthase, Jeffrey C. Moffat

Theses and Dissertations

Proton channels are essential for many of the processes of life. The influenza A viral protein M2 is responsible for sensing the conditions necessary for viral RNA release. The proton-translocating FoF1 ATPase (ATP synthase) uses a proton gradient to drive adenosine triphosphate (ATP) synthesis. We have directly measured proton uptake in vesicles containing reconstituted M2 or FO by monitoring external pH after addition of valinomycin to vesicles with 100-fold diluted external [K+]. This proton flux assay was utilized to quantify proton flux through single M2 and Fo channels. Contrary to previous reports, proton uptake by M2 was not significantly altered …

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Geologic Map And Structural Analysis Of The Twin Rocks 7.5 Minute Quadrangle, Wayne County, Utah, Samuel C. Sorber Jun 2006

Geologic Map And Structural Analysis Of The Twin Rocks 7.5 Minute Quadrangle, Wayne County, Utah, Samuel C. Sorber

Theses and Dissertations

A new geologic map of the Twin Rocks 7.5 minute quadrangle primarily located within Capitol Reef National Park, south-central Utah, provides stratigraphic and structural detail not previously available. This map has also been instrumental in understanding the evolution and development of fluvial terraces associated with Sulfur Creek and the structural geology of the backlimb of the Miners Mountain uplift. Nine bedrock stratigraphic formations and eight types of Quaternary deposits were mapped throughout the quadrangle. Bedrock stratigraphy ranges in age from Permian to Jurassic. New details absent on previous geologic maps include members of the Chinle and Moenkopi Formations and the …

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Superficial Self-Harm Behavior: Helping Young Women Who Hurt Themselves, Katherine D. Ryan Jun 2006

Superficial Self-Harm Behavior: Helping Young Women Who Hurt Themselves, Katherine D. Ryan

Theses and Dissertations

Roughly 1 to 4% of the population engages in self-harm. Superficial self-harm is reported by more young women, than young men. Appropriate responses from family, friends, and other important individuals are a key ingredient in facilitating recovery. Non-therapists, such as family, friends, and school personnel often wish to assist young women who self-harm, but the problem is complex and they are often unsure of how to respond. Current studies primarily focus on the clinical interventions for self-harm, while very few have investigated the perspectives of the individuals who self-harm. This study investigated the perspectives of young women who self-harm in …

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Fibroblast Migration And Collagen Deposition During Dermal Wound Healing: Mathematical Modelling And Clinical Implications, S. Mcdougall, J. A. Sherratt, P. K. Maini, J. C. Dallon Jun 2006

Fibroblast Migration And Collagen Deposition During Dermal Wound Healing: Mathematical Modelling And Clinical Implications, S. Mcdougall, J. A. Sherratt, P. K. Maini, J. C. Dallon

Faculty Publications

The extent to which collagen alignment occurs during dermal wound healing determines the severity of scar tissue formation. We have modelled this using a multiscale approach, in which extracellular materials, for example collagen and fibrin, are modelled as continua, while fibroblasts are considered as discrete units. Within this model framework, we have explored the effects that different parameters have on the alignment process, and we have used the model to investigate how manipulation of transforming growth factor-b levels can reduce scar tissue formation. We briefly review this body of work, then extend the modelling framework to investigate the role played …

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The Mechanism Of Assembly Of The G-Protein Beta Gamma Subunit Dimer By Ck2 Phosphorylated Phosducin-Like Protein And The Chaperonin Containing Tcp-1, Christine M. Baker Jun 2006

The Mechanism Of Assembly Of The G-Protein Beta Gamma Subunit Dimer By Ck2 Phosphorylated Phosducin-Like Protein And The Chaperonin Containing Tcp-1, Christine M. Baker

Theses and Dissertations

Phosducin-like protein (PhLP) binds G-protein beta gamma subunits and is thought to assist in assembly of the G-protein beta gamma dimer. Phosphorylation of PhLP at serine residues 18-20 by the casein kinase 2 (CK2) appears to play an essential role in this process. PhLP has also been shown to interact with the chaperonin containing TCP-1 (CCT) atop its apical domain, not entering the substrate folding cavity. However, the physiological role of the PhLP-CCT interaction in G-protein beta gamma dimer formation remains unclear. This study addresses the mechanism of G-protein beta gamma assembly by exploring the specific roles of CCT and …

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Active Learning In A Large Enrollment Introductory Biology Class: Problem Solving, Formative Feedback, And Teaching As Learning, Diane Flint Robison Jun 2006

Active Learning In A Large Enrollment Introductory Biology Class: Problem Solving, Formative Feedback, And Teaching As Learning, Diane Flint Robison

Theses and Dissertations

The purpose of this study was to take a case study approach to exploring student learning experiences in a large enrollment introductory biology class. Traditionally such classes are taught through the lecture method with limited instructor-student interaction and minimal student-centered learning (Lewis & Woodward, 1984; Wulff, Nyquist, & Abbott, 1987). Biology 120 taught at Brigham Young University winter semester 2006 by John Bell was chosen as the case for the study due to its large enrollment (263) and its innovative pedagogy. In the classroom, students applied their learning through a variety of student-centered activities including solving problems, discussing concepts with …

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How Parents And Their Adolescent Children "Talk The Talk" In Religious Conversations, Jennifer Yorgason Thatcher Jun 2006

How Parents And Their Adolescent Children "Talk The Talk" In Religious Conversations, Jennifer Yorgason Thatcher

Theses and Dissertations

This study builds on previous research regarding parent-child religious conversations to explore the elements and bidirectional processes of parent-adolescent religious conversations. It employs qualitative analyses of interviews with highly religious parents and adolescents representing the major Abrahamic faiths (Christianity, Judaism, Islam) from New England and Northern California. Variations in content, structure, conversational processes, and bidirectional influence are summarized in a conceptual model. Findings suggest that the quality of conversations is greater for parents and adolescents when they are youth-centered than when they are parent-centered.

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The Relationship Of Implicit Family Process Rules To Adolescent Presentation Of Psychological Systems, Ian David Feinauer Jun 2006

The Relationship Of Implicit Family Process Rules To Adolescent Presentation Of Psychological Systems, Ian David Feinauer

Theses and Dissertations

Implicit family process rules refer to unspoken rules about family beliefs and expectations about communication, closeness, and organization and are an important dimension of family functioning that may have a powerful influence over adolescent psychological well being. This study focused on the relationship between implicit family process rules and adolescent psychological symptoms such as: Hostility, interpersonal sensitivity, depression, anxiety, and somatization. It was hypothesized that more facilitative implicit family process rules would be related to fewer adolescent psychological symptoms. In addition, a model was created that included theexogenousindependent variables of family status, (defined as intact-marriage or non-intact), treatment status (whether …

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Influence Of Age On Auditory Gating, Ginny Marissa Smith Jun 2006

Influence Of Age On Auditory Gating, Ginny Marissa Smith

Theses and Dissertations

This study utilized paired tones at 1000 Hz with a 500 ms interpair interval and a 10 s interstimulus interval to assess sensory gating. Forty-two participants, ranging from 3-72 years of age were used to observe maturational changes in amplitude, latency, and suppression ratios of the P50 waveform. Previous research has shown that in normal adults the amplitude in response to the second of the paired tones is significantly suppressed compared to the amplitude in response to the first tone. The current study showed amplitude decreased with age to middle adulthood, where it increased slightly to later adulthood. Latencies decreased …

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Fabrication Of Polymeric Microfluidic Devices For Protein Analysis, Jikun Liu Jun 2006

Fabrication Of Polymeric Microfluidic Devices For Protein Analysis, Jikun Liu

Theses and Dissertations

2-Bromoisobutyryl bromide was immobilized on poly(methyl methacrylate) (PMMA) substrates activated using an oxygen plasma. Atom-transfer radical polymerization was then performed to graft poly(ethylene glycol) (PEG) on the PMMA surface. PMMA micro capillary electrophoresis (µCE) devices made with the covalently modified surfaces exhibited substantially reduced electroosmotic flow and nonspecific adsorption of proteins. Both column efficiency and migration time reproducibility were one order of magnitude better with derivatized PMMA µCE devices compared to untreated versions. Fast, reproducible, and efficient separations of proteins and peptides were demonstrated using the PEG-grafted PMMA µCE chips. All analyses were completed in less than 60 seconds, and …

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Medical Model Influence In Counseling And Psychotherapy: Counseling Psychology Training Directors' Views, Dallas R. Jensen Jun 2006

Medical Model Influence In Counseling And Psychotherapy: Counseling Psychology Training Directors' Views, Dallas R. Jensen

Theses and Dissertations

The practice of counseling and psychotherapy is influenced by a number of ideologies, models, and paradigms. Among these, the medical model's influence is particularly salient. The ideology of the medical field pervades the theory, research, and practice of psychology and its influence deserves close examination. The few studies in this area that have been conducted are descriptive and basic in nature. The present study aimed to contribute richness and depth to conversations about medical model influence. By interviewing Counseling Psychology training directors and applying a qualitative analysis, this study provided the following themes that characterize views of the medical model's …

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Internalized Shame As A Moderating Variable For Inhibited Sexual Difficulties In Adult Women Resulting From Childhood Sexual Abuse, Kristine Robinson May 2006

Internalized Shame As A Moderating Variable For Inhibited Sexual Difficulties In Adult Women Resulting From Childhood Sexual Abuse, Kristine Robinson

Theses and Dissertations

An adult female sample of childhood sexual abuse survivors (N=467) were surveyed to determine whether internalized shame moderated the effects of sexual inhibited difficulties. Other variables such as severity, duration, and frequency of sexual abuse, as well as whether physical abuse was also part of their experience, were examined to determine their role in later sexual inhibition. It was predicted that there would be a significant positive relationship between 1) Scores on variables of physical abuse, severity of abuse, frequency of abuse, duration of abuse, identity of the perpetrator and scores on the variable of inhibited sexual difficulties; 2) Scores …

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Relation Of Fish Communities To Environmental Conditions In Urban Streams Of The Wasatch Front, Utah, Elise M. Giddings, Larry R. Brown, Terry M. Short, Michael R. Meador May 2006

Relation Of Fish Communities To Environmental Conditions In Urban Streams Of The Wasatch Front, Utah, Elise M. Giddings, Larry R. Brown, Terry M. Short, Michael R. Meador

Western North American Naturalist

Twenty-eight sites along the Wasatch Front, north central Utah, representing the range of urban land use intensity for wadeable streams of the area, were sampled in September 2000. Fish communities were assessed by single-pass electrofishing, and physical habitat and water-quality characteristics were measured. On average, nonnative species comprised 54% of species richness and 53% of relative abundance, although only Salmo trutta and Pimephales promelas were very abundant at any 1 site. Salmo trutta and Catostomus platyrhynchus, a native species, were the most widely distributed and abundant species captured. Analysis of fish communities using nonmetric multidimensional scaling (NMDS) revealed a …

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Comparison Of Gila Topminnow And Western Mosquitofish As Biological Control Agents Of Mosquitoes, Michael R. Childs May 2006

Comparison Of Gila Topminnow And Western Mosquitofish As Biological Control Agents Of Mosquitoes, Michael R. Childs

Western North American Naturalist

I compared acute tolerance of Gila topminnow, Poeciliopsis occidentalis, and western mosquitofish, Gambusia affinis, to ammonia and high water temperature and also compared diet, food selectivity, and impact on invertebrate populations to evaluate the potential for each species to effectively control mosquitoes (Culicidae) in wetland habitats. Critical thermal maxima differed among species, sexes, and lifestages, but these differences were likely not biologically significant due to their small magnitude and the ability of wild populations of both species to adapt to high temperatures. In 24-hour tests, G. affinis displayed about twice the ammonia tolerance as did P. occidentalis. …

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Tamarix Aphylla: A Newly Invasive Tree In Southern Nevada, Lawrence R. Walker, Pamela L. Barnes, Elizabeth A. Powell May 2006

Tamarix Aphylla: A Newly Invasive Tree In Southern Nevada, Lawrence R. Walker, Pamela L. Barnes, Elizabeth A. Powell

Western North American Naturalist

In the southwestern United States, the nonnative athel pine (Tamarix aphylla) was presumed to be sterile and therefore not as likely to spread as its widely distributed, nonnative congener, T. ramosissima. However, at Lake Mead National Recreation Area (LMNRA) in southern Nevada, populations of T. aphylla have recently spread beyond their limited pre-1990 distribution and now form extensive monospecific stands. Over a 3-year period, we quantified seed production and germination from 60 T. aphylla trees at LMNRA. The annual mean seed production period was 50.6 days, and the mean potential germination (under laboratory conditions) was 22%, indicating …

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The Effect Of Livestock Grazing On The Rainbow Grasshopper: Population Differences And Ecological Correlates, Sandra J. Debano May 2006

The Effect Of Livestock Grazing On The Rainbow Grasshopper: Population Differences And Ecological Correlates, Sandra J. Debano

Western North American Naturalist

This study examined the effect of livestock grazing on a common herbivore in semiarid grasslands of the Southwest: the rainbow grasshopper, Dactylotum variegatum. Population attributes and key environmental variables were compared between sites on active cattle ranches and sites on a 3160-ha ungrazed sanctuary. Although density of D. variegatum nymphs did not differ significantly between grazed and ungrazed sites, adult density was significantly lower on grazed sites, and sex ratios differed between grazed and ungrazed sites over time. Grazed sites had higher percentages of bare ground and fewer Baccharis pteronioides, a common shrub. However, only bare ground was …

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First Record Of Calochortus Apiculatus (Liliaceae) In Wyoming, Joseph R. Thomasson, Scott A. Thomasson, Daryl E. Mergen May 2006

First Record Of Calochortus Apiculatus (Liliaceae) In Wyoming, Joseph R. Thomasson, Scott A. Thomasson, Daryl E. Mergen

Western North American Naturalist

No abstract provided.

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Observations On The Reproductive Biology Of Roundtail Chub, Gila Robusta, In The Upper Verde River, Arizona, Mark J. Brouder, Diana D. Rogers, Lorraine D. Avenetti May 2006

Observations On The Reproductive Biology Of Roundtail Chub, Gila Robusta, In The Upper Verde River, Arizona, Mark J. Brouder, Diana D. Rogers, Lorraine D. Avenetti

Western North American Naturalist

No abstract provided.

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San Francisco's Golden Gate: A Bridge Between Historically Distinct Coyote (Canis Latrans) Populations?, Benjamin N. Sacks, Holly B. Ernest, Erin E. Boydston May 2006

San Francisco's Golden Gate: A Bridge Between Historically Distinct Coyote (Canis Latrans) Populations?, Benjamin N. Sacks, Holly B. Ernest, Erin E. Boydston

Western North American Naturalist

No abstract provided.

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Current Records Of The Mexican Long-Tongued Bat, Choeronycteris Mexicana, In Baja California, Mexico, Ruben Couoh–De La Garza, Emma Flores-Rojas, Nazdry Briones-Escobedo, Eiracitlalli Hernández–Del Angel, Roberto Martínez-Gallardo, Juana Claudia Leyva Aguilera May 2006

Current Records Of The Mexican Long-Tongued Bat, Choeronycteris Mexicana, In Baja California, Mexico, Ruben Couoh–De La Garza, Emma Flores-Rojas, Nazdry Briones-Escobedo, Eiracitlalli Hernández–Del Angel, Roberto Martínez-Gallardo, Juana Claudia Leyva Aguilera

Western North American Naturalist

No abstract provided.

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New Records Of The Eastern Pipistrelle (Pipistrellus Subflavus) In Colorado, David M. Armstrong, Rick A. Adams, Karen E. Taylor May 2006

New Records Of The Eastern Pipistrelle (Pipistrellus Subflavus) In Colorado, David M. Armstrong, Rick A. Adams, Karen E. Taylor

Western North American Naturalist

No abstract provided.

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Plant Species Richness At Different Scales In Native And Exotic Grasslands In Southeastern Arizona, Steven P. Mclaughlin, Janice E. Bowers May 2006

Plant Species Richness At Different Scales In Native And Exotic Grasslands In Southeastern Arizona, Steven P. Mclaughlin, Janice E. Bowers

Western North American Naturalist

Species richness in Madrean mixed-grass prairies dominated by native or exotic species in southeastern Arizona was characterized at the community and point scales using ten 1-m2 quadrats nested within each of eight 1000-m2 plots. In the 1000-m2 plots average richness was significantly higher in oak savanna (OS, 121.0 species) than in exotic grassland on mesa tops (EMT, 52.0 species), whereas native grassland on mesa slopes (NMS, 92.5 species) and native grassland on mesa tops (NMT, 77.0 species) did not differ significantly in richness from OS or EMT. When richness was partitioned by life form, EMT was notably …

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Observations Of Selected True Bugs (Hemiptera: Heteroptera) Of The Pacific Northwest Shrubsteppe Zone, John D. Lattin May 2006

Observations Of Selected True Bugs (Hemiptera: Heteroptera) Of The Pacific Northwest Shrubsteppe Zone, John D. Lattin

Western North American Naturalist

No abstract provided.

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Characteristics Of Swift Fox Dens In Northwest Texas, Brady K. Mcgee, Kerry L. Nicholson, Warren B. Ballard, Matthew J. Butler May 2006

Characteristics Of Swift Fox Dens In Northwest Texas, Brady K. Mcgee, Kerry L. Nicholson, Warren B. Ballard, Matthew J. Butler

Western North American Naturalist

The swift fox (Vulpes velox) was classified in 1995 as a candidate for listing under the Endangered Species Act. Since then, several studies have addressed survey methods for monitoring swift fox populations. The purpose of this paper is to assist field researchers in documenting the presence of swift foxes by identification of recently active den sites. We propose that swift foxes have unique external den characteristics that can be distinguished during aerial surveys. We collected data from 30 swift fox den complexes on both continuous rangeland and landscapes fragmented by cropland in northwest Texas. There were no differences …

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Growth Rate And Thermal Tolerance Of Two Endangered Snake River Snails, Steven Lysne, Peter Koetsier May 2006

Growth Rate And Thermal Tolerance Of Two Endangered Snake River Snails, Steven Lysne, Peter Koetsier

Western North American Naturalist

We investigated the temperature tolerance and growth of 2 federally protected freshwater gastropods from southern Idaho: Valvata utahensis and Pyrgulopsis idahoensis. Snails were collected in the Snake River and transported to the laboratory where they were kept under highly controlled conditions. In varying-temperature, short-duration experiments, the temperatures tolerated by both species were between 7°C and 34°C. In constant-temperature, long-duration experiments, growth rates were between 0.004 mm · d−1 and 0.016 mm · d−1, and we created growth curves for both species that were previously lacking. Our results are among the first to report temperature tolerances and …

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Age And Population Structure Of Joshua Trees (Yucca Brevifolia) In The Northwestern Mojave Desert, Kimberly D. Gilliland, Nancy J. Huntly, J. E. Anderson May 2006

Age And Population Structure Of Joshua Trees (Yucca Brevifolia) In The Northwestern Mojave Desert, Kimberly D. Gilliland, Nancy J. Huntly, J. E. Anderson

Western North American Naturalist

Many desert perennials are long-lived, but there are few data on ages or population structures of desert plants. We used 2 methods to estimate ages of a population of Yucca brevifolia (Joshua tree) in southwestern Utah from a 14-year census of plant sizes. Plant height at the 1st census ranged from 0.08 m to 6.0 m, and trees grew in height at a mean rate of 3.75 cm · yr−1. Plants also increased slowly in basal diameter (0.142 cm · yr−1) and branch length (0.024 m · yr−1), but basal diameter varied greatly from …

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