Stem growth and longevity dynamics for Salix arizonica dorn

Diameter-age relationships of Salix arizonica (Arizona willow) stems were investigated for 5 populations on the Markagunt, Paunsaugunt, and Sevier plateaus in southern and central Utah. Of the 430 stems studied, none exceeded 26 mm in diameter at ground level (estimated age of 19 yr). Equations developed for predicting age from stem diameters consistently accounted for over 90% of the observed variation. Slopes of predictive equations were homogenous across the 3 sites considered in detail. At 2 sties 46% and 38% of the stems exceed 10 mm (～ 7 yr old) diameter at ground level. At a 3rd site, no stems survived to exceed that size. Stem-age profiles at specific sites may thus be useful for assessing the relative favorability of local environments for the species.     

Morphological and genetic variation among populations of the rare Kachina daisy ( Erigeron kachinensis ) from southeastern Utah

Erigeron kachinensis , the Kachina daisy, is a rare species restricted to canyons in southeastern Utah. The species is known to exhibit low fecundity due to low percent fertilization of ovules and high percent abortion of fertilized ovules. Previous reproductive studies suggest that low fecundity is a consequence of small population size and inbreeding depression. This study examines genetic diversity within and among populations of E. kachinensis in Natural Bridges National Monument using enzyme electrophoresis. Field populations are found to have significantly different morphologies. However, morphological differences were less pronounced among populations grown in the greenhouse. The Kachina daisy exhibits levels of genetic variability in its populations similar to that of other outcrossed species. Genetic diversity statistics demonstrate that only 22.8% of genetic variation is distributed among populations. Genetic distance could not be correlated with geographic distance. Most of the populations showed significant deviation of fixation indices from zero for multiple loci. Observation of genotype frequencies demonstrates that populations are fixing on different genotypes and may be experiencing initial stages of genetic drift. Mean observed heterozygosity was 0.166 and was found to increase with increasing size and/or age in populations.     

The successional status of Cupressus arizonica

Several investigations (size-class analysis, age-determination inquiries, and germination tests) suggest that Cupressus arizonica of southeastern Arizona is a pioneer species. The tree requires disturbance to remove or reduce soil litter, which otherwise inhibits the reproduction of the species. Reduction of light intensity caused by canopy closure appears to be less important than litter accumulation in restricting C. arizonica reproduction. Following disturbance, successful establishment of seedlings may occur over an extended period (50 to 100 years), as litter gradually accumulates. The absence of C. arizonica seedlings in present populations suggest that fire suppression policies on federal lands where C. arizonica occurs have altered fire frequency, and consequently have fostered a short-term reduction in C. arizonica establishment. Only in floodplain environments, where flooding disturbs the soil surface, has much reproduction occurred in recent years. The long-term population pattern of C. arizonica appears stable, due to the great longevity of the species.     

Effects of fragmentation on genetic variation in populations of the terrestrial earthworm Drawida japonica Michaelsen, 1892 (Oligochaeta,Moniligastridae) in Shandong and Liaodong peninsulas,China

Earthworms are excellent indicators of landscape fragmentation due to their widespread distribution and poor dispersal abilities over water. Based on field studies conducted in the Shandong and Liaodong peninsulas and their associated islands during summer 2009, we analysed the genetic variation of Drawida japonica Michaelsen, 1892 (Oligochaeta, Moniligastridae) using DNA sequences of the 16S and 28S ribosomal genes in samples obtained from 13 localities, 12 of which were islands, one artificially connected to the mainland by man (Yangma SC). We identified 55 haplotypes among 79 samples, based on 1094 bp, including 47 unique haplotypes. The phylogenetic tree topologies showed two distinct clades. A multiple-apex Poisson distribution using a mismatch analysis of nucleotides was also detected. Results of a Tajima D neutral test were not significant (p > 0.05). Genetic divergence among populations was much larger than within populations. A positive relationship between genetic diversity and island area was revealed, but no significant correlation between genetic diversity and distance to the nearest larger landmass was found. These results indicate that the intraspecific genetic diversity of D. japonica has been influenced by geographic isolation (i.e. island habitat). Passive transport via anthropogenic activities or nonhuman vertebrates (birds or mammals) may also play a key role in dispersal.     

Genetic diversity and low reproductive success in isolated populations of Utah juniper ( Juniperus osteosperma , Cupressaceae)

Utah juniper ( Juniperus osteosperma ) has greatly expanded its historical range in the western United States. Management plans for the species have focused on curtailing its encroachment into sagebrush and grassland communities. These plans often include burning or other methods of elimination. These methods may result in subdivision or fragmentation of existing juniper stands. We initiated a study at Dugway Proving Ground, a U.S. Army facility, to examine the effects of fragmentation on the reproductive success of Utah juniper in isolated populations. We used enzyme electrophoresis to quantify genetic variability in isolated populations. We also determined population reproductive success by examining juniper fruits for evidence of seed abortion and/or presence of insect parasites. We compared reproductive and genetic variability in isolated populations at Dugway to 2 nonisolated and encroaching Utah juniper populations. The Dugway populations exhibited reduced seed set due to high seed abortion and/or insect seed parasitism, and a loss of genetic variability in comparison to the nonisolated populations. Additionally, there was a significant correlation between reproductive success and genetic variability.     

Genetic structure in striped skunks ( Mephitis mephitis ) on the Southern High Plains of Texas

Genetic variation within populations reflects population-level social and demographic processes and influences how a population behaves as an evolutionary unit. We examined partitioning of genetic variation in striped skunks ( Mephitis mephitis ) from the Southern High Plains of Texas during 1994-1995. Sixty-nine male and 35 female skunks were sampled on four 12.8-km 2 study plots. Plot centers ranged from 17.6 to 61.6 km apart. We used multi-locus DNA fingerprinting with 2 probes, pV47 and CTTxAGG, to test 3 hypotheses: (1) females are more genetically similar to other females than males are to other males on the same plot (indicating greater female philopatry than male philopatry), (2) genetic similarity is greater within plots than among plots (indicating partitioning of genetic variation in space), and (3) genetic similarity of males decreases as the distance separating males increases (indicating geographic distance affects rates of gene flow). In general, males on a plot had lower average genetic similarity than females. Genetic similarity within plots was not different from genetic similarity among plots for males or for females. Genetic similarity of males did not decrease with increasing distance among plots. The lack of geographical genetic structure in striped skunks suggests at the scale of this study (< 60 km) that gene flow of biparentally inherited genes is not distance-mediated. However, the higher similarity values for females than for males on the same plot supports an effect of male-biased dispersal and female philopatry on partitioning of genetic variation between sexes.     

Range extension of Helianthus spp. (Asteraceae) in Arizona and Utah

Two populations of Helianthus niveus (Benth.) Brandegee ssp. canescens (A. Gray) Heiser were discovered in northern Arizona extending the range 300 miles north for this species. Helianthus deserticola Heiser range was extended 100 miles east in both Arizona and Utah.     

Response of winterfat ( Ceratoides lanata ) communities to release from grazing pressure

Sixteen study sites were established in grazed and ungrazed stands of winterfat in Kane County, Utah. The area is located within the winter range of cattle and along U.S. Highway 89 between Kanab, Utah, and Page, Arizona. Road construction in 1957 dissected several winterfat communities, and following fencing part of the communities were released from grazing. Differences in species composition, vegetation, and soil characteristics between grazed and ungrazed sites were assessed. Major differences in site characteristics appeared due to the influence of winter grazing by cattle. Winterfat and Indian ricegrass showed increased cover on the nongrazed sites following release from grazing pressure. Winterfat also showed significant negative interspecific association patterns with all major species.     

Carbon isotope discrimination and water relations of oak hybrid populations in southwestern Utah

The evergreen oak Quercus turbinella and the deciduous Q. gambelii form natural hybrids in southwestern Utah and northern Arizona. Hybrid individuals also are found in northern Utah in a region where only Q. gambelii currently exists, indicating that Q. turbinella has recently retreated southward. Our objectives were to (1) examine the ecophysiology of parental taxa and hybrids under natural conditions in southeastern Utah, and (2) investigate the level of integration between leaf carbon isotope discrimination (a synthetic gas exchange trait) and structural and chemical traits of leaves in morphologically variable hybrid populations. Leaf length, width, mass-to-area ratio (LMA, g m -2 ), and nitrogen concentration (N, g g -1 ) within 2 hybrid populations near New Harmony, Utah, were highly intercorrelated. Variation within the hybrid populations spanned mean values for these traits observed in parental taxa from adjacent ""pure"" populations of each species. Carbon isotope discrimination (Δ), an integrated measure of the ratio of intercellular to ambient CO 2 concentration, ranged from 16.1‰ to 19.6‰ within the 2 hybrid populations and was positively correlated with leaf nitrogen concentration and negatively correlated with LMA; individuals in hybrid populations with leaves resembling Q. gambelii had the highest leaf Δ and N concentrations and lowest LMA compared with leaves from plants that resembled Q. turbinella . CO 2 uptake is limited by stomatal conductance and possibly by mesophyll resistance to a greater extent in Q. turbinella phenotypes than in intermediate or Q. gambelii phenotypes. δD of stem xylem water (an indication of active rooting depth) and predawn water potential during the peak monsoon period in August were not correlated to leaf Δ values within the hybrid populations. Several individuals that were morphologically similar to Q. turbinella in the hybrid populations maintained high predawn water potentials and derived moisture from winter recharge that presumably was taken from deep soil layers. Apparently, a few adult individuals of the Q. turbinella phenotype in hybrid populations accessed water from deep in the soil profile, which enabled them to avoid summer drought. Reduced monsoonal activity may have been an important, but not the single, determinant of Q. turbinella s retreat from northern Utah during the recent Holocene.     

Notes on significant collections and additions to the flora of Glen Canyon National Recreation Area, Utah and Arizona, between 1992 and 2004

Symphyotrichum expansum (Puepp ex Spreng.) Nesom is reported new to Utah from the Escalante River drainage. A major range extension is reported for Aralia racemosa L. in the Escalante drainage, and additional populations are reported of the rare species Imperata brevifolia Vasey in Utah, including the 1st record for the Grand Staircase--Escalante National Monument. Heterotheca grandiflora Nutt. is reported new to north central Arizona. New locations and notes on an additional 22 rare species in Glen Canyon National Recreation Area are listed.     

Checklist of the mosses of Grand Teton National Park and Teton County, Wyoming

Symphyotrichum expansum (Puepp ex Spreng.) Nesom is reported new to Utah from the Escalante River drainage. A major range extension is reported for Aralia racemosa L. in the Escalante drainage, and additional populations are reported of the rare species Imperata brevifolia Vasey in Utah, including the 1st record for the Grand Staircase--Escalante National Monument. Heterotheca grandiflora Nutt. is reported new to north central Arizona. New locations and notes on an additional 22 rare species in Glen Canyon National Recreation Area are listed.     

Beetles from the environs of Lake Powell in southern Utah and northern Arizona

Sixty-eight species of beetles of 14 families were collected in pit traps in 12 major vegetative communities during environmental monitoring studies in the summers of 1971 to 1973 in southern Utah and northern Arizona. Seasonal and plant community differences and correlations in population and composition were noted for the 16 sites studied. Highest populations and the most species were found in a grass community, but occurred in different months in each of the three years. Lowest populations were found in a Coleogyne community, and fewest species in an Artemisia- grass community.     

Biochemical differentiation in the Idaho ground squirrel, Spermophilus brunneus (Rodenta: Scuridae)

Spermophilus brunneus is restricted to a 90 × 125-km area of west central Idaho, with two distinct (northern and southern) groups of populations within this limited range. Morphological differences in pelage length and coloration, external and cranial measurements, and bacula suggest that these groups are either very distinct subspecies or species. We used starch-gel electrophoresis to estimate the amount of genetic differentiation accompanying these morphological differences by assaying genetic variation at 31 loci in the two geographic groups. Fifteen loci were polymorphic (13 in the northern group, 12 in the southern), and mean heterozygosity (H) was high (12.3% northern and 10.8% southern). Nei's genetic distance (0.057) is in the range usually associated with subspecific differences. However, Jaccard's association coefficient (0.893) is about the same as that found between several ground squirrel taxa currently recognized as species. The high levels of heterozygosity suggest that S. brunneus is a neoendemic rather than a paleoendemic species.     

Allozyme variability, isolation, and dispersal of Eusattus muricatus (Coleoptera: Tenebrionidae) within Silver State Dune Complex, Great Basin, western North America

Genetics of Eusattus muricatus (Coleoptera: Tenebrionidae) populations within Silver State Dune Complex in the northern Great Basin of North America were assayed using allozyme electrophoresis. Hierarchical F -statistics showed no significant population subdivision among 3 valleys comprising Silver State Dune Complex. A regression of estimated pairwise gene flow ( Nm ) against pairwise geographic distance was not significant for populations within these valleys, but it was significant over larger distances. A neighbor-joining phenogram did not represent geographic relationships among populations in the 3 valleys but reflected the past geologic history of these dunes. Pairwise divergence times were low (&#62;7000 yr) for populations within Silver State Dune Complex but were high (&#62;18,000 yr) in outgroups.     

Taxonomy of Sphaeromeria, Artemisia , and Tanacetum (Compositae, Anthemideae) based on randomly amplified polymorphic DNA (RAPD)

Relationships within, between, and among the Anthemideae genera Sphaeromeria, Artemisia , and Tanacetum were investigated using 238 randomly amplified polymorphic DNA (RAPD) markers obtained from twenty 10-mer primers amplified on genomic DNA. Forty-one populations from 16 taxa (15 species) were studied. Jaccard's coefficient of similarity and UPGMA clustering analysis were used to construct phenograms. T tests were used to make comparisons between samples at various systematic levels. DNA markers were 75% similar for conspecific populations. Sixteen Sphaeromeria populations (5 species) showed an average interspecific similarity of 21%. Interspecific similarity among 23 Artemisia populations (8 species with 2 subspecies of A. tridentata included) averaged 27%. Two Tanacetum species (1 population each) were 89% similar. The high similarity of Tanacetum species was in the range of observed values for conspecific populations; indeed those 2 species ( T. vulgare and T. boreale ) have been considered conspecific by some authors. The 3 subgenera of Artemisia studied ( Artemisia, Dracunculus , and Tridentatae ) formed separate groups. In comparison among the genera, Sphaeromeria was 18% similar to Artemisia (more similar to subgenus Tridentatae than the other Artemisia subgenera); intergeneric comparisons of Sphaeromeria and Artemisia and Tanacetum , which supports previously established morphological distinctions. Sphaeromeria potentilloides may be misplaced in the genus Sphaeromeria based on DNA marker results. It is likely that North American Anthemideae are circumboreal derivatives of ancestral Eurasian stock and that Sphaeromeria is derived from an Artemisia -like ancestor.     

Strong genetic differentiation among neighboring populations of a locally endemic primrose

Maguire primrose is a locally endemic plant of northern Utah, USA, with a total known range of less than 20 km 2 . A previous study found evidence for strong differentiation among local populations at 4 allozyme loci. Here we reexamined populations using 165 AFLP loci and found further evidence of unusually strong genetic structure. We also found an apparently fixed nucleotide difference between populations for a noncoding region of chloroplast DNA, mirroring the patterns seen for AFLP loci. Furthermore, we tested the hypothesis that the current population structure is the result of breeding barriers between plants from different populations. We made controlled hand-pollinated crosses and found that interpopulation crosses did not set significantly fewer seeds than intrapopulation crosses. Thus, we found no evidence of breeding barriers to explain these genetic patterns. However, we did note a relatively short overlap in flowering time, suggesting that phenology is a more feasible explanation for genetic differentiation than pollen-stigma incompatibility. Our study emphasizes that even locally endemic plants can house measurable genetic differences over a short geographic scale.     

Geographical review of the historical and current status of Ospreys ( Pandion haliaetus ) in Utah

A small numbers of Ospreys ( Pandion haliaetus ) are known to have nested historically in Utah. A precise baseline figure is unavailable, but the 19th-century Osprey population in Utah probably consisted of at least 15 breeding pairs scattered in 4 geographic regions. Human persecution is believed to have caused the abandonment of nesting territories along the Wasatch Front and in the western Uinta Mountains by 1900 and 1960, respectively. Osprey populations in the southern plateaus and Green River areas, however, began increasing in the late 1970s. Several recent nesting attempts and numerous summer sightings at nontraditional and abandoned historical sites in Utah suggest the Osprey is also expanding its range in Utah. High productivity for local pairs and long-range dispersal from more northerly Osprey populations are discussed as sources for the current surge in Utah's Osprey population, which now consists of approximately 35 breeding pairs.     

Genetic structuring at a fine scale in the russet-crowned motmot ( Momotus mexicanus ) in a tropical dry forest in central Mexico

Because of their high dispersal abilities, birds are expected to manifest marked genetic structuring only at relatively large geographic scales. However, it is not well known how factors like nest site fidelity in a largely resident species could limit gene flow and increase genetic structuring in birds. In this study we use RAPD markers to estimate genetic structuring in a strongly sedentary species of the American tropics, the Russet crowned Motmot ( Momotus mexicanus ), within a tropical dry forest in central Mexico. Genetic structuring was assessed among 3 populations separated by a mean distance of only 25 km. We report that 12.9% of the total genetic variation is explained by differences among sites, which is quite high for a bird at this geographic scale. We propose that high nest site fidelity, brought on by a scarcity of suitable nest substrates, may be responsible for high genetic structuring in this species.     

Reestablishment of Stenogonum Nutt. (Polygonaceae)

The genus Stenogonum Nutt. (Polygonaceae) is reestablished and distinguished from Eriogonum Michx. with which it has been synonymized since 1853. The genus, as outlined here, differs from Eriogonum in having two whorls of three foliaceous bracts surrounding the flowers instead of the normal, united tubular involucre. Stenogonum contains two species, S. flexum and S. salsuginosum; they are restricted primarily to the Colorado Plateau of Wyoming southward through eastern Utah and western Colorado to northwestern New Mexico and adjacent northern Arizona. Both species are illustrated and their respective ranges mapped.     

New record of the bat Plecotus phyllotis from Utah

In June 1974 a scrotal male Mexican big - eared bat ( Plecotus phyllotis ) was netted near Hurricane, Utah. This account represents the third report of the species from Utah and extends the range approximately 330 km west of previous accounts. Adjacent state records are located approximately 64 km to the southeast in Arizona and 80 km southwest in Nevada.