Genetic differentiation of rare and common varieties of Eriogonum shockleyi (Polygonaceae) in Idaho using ISSR variability

Idaho populations of Eriogonum shockleyi are divided taxonomically into 2 varieties: E. shockleyi var. packardae , which is endemic to Idaho, and the typical variety, which is widespread in the western United States. Recent morphological investigations of E. shockleyi in Idaho have identified potentially reliable morphological characters for field identification of the subspecific taxa. This paper investigates the genetic basis for the separation of the 2 varieties of E. shockleyi using inter simple-sequence repeats (ISSR) markers. Although we found some morphological differences between the populations that correlated with the 2 varieties, we identified no molecular markers in this study to distinguish between them. Morphological measurements obtained in the field indicate that although a population may have an overall average morphology that defines the variety, some individuals in nearly all populations have putative diagnostic characters that define the other variety. The morphological characters used to distinguish the 2 varieties are most likely the result of environmental variability and could result from differences in precipitation and soil water retention. Alternatively, high levels of outcrossing through pollen flow could be obscuring selection for morphological characters at particular sites.     

Great Basin summer range forage quality: do plants nutrients meet elk requirements?

Understanding the relative ability of forages to meet the needs of prime-age females, the productive component of elk ( Cervus elaphus ) populations, is necessary to decipher reasons for declines and potential for population growth. Information on forage nutrient dynamics for elk on Great Basin summer-fall ranges is lacking. Our primary objectives were to estimate nutrient levels in common elk forage species in northeastern Nevada at 3 time periods and evaluate whether nutrient levels met good requirements for lactating cow elk at time periods across summers. We compared crude protein, digestible energy, and macromineral levels in 2 forbs, 6 grasses, and 4 woody browse forage species to requirements for lactating cow elk in early summer, midsummer, and early fall 1999 and 2000. Spurred lupine ( Lupinus caudatus ) and snowbrush ceanothus ( Ceanothus velutinus ) were the most proteinaceous plants, exceeding requirements across all seasons. By midsummer, protein levels in all grasses were below elk requirements (12%). Digestible energy was the most limiting nutrient with woody browse meeting lactating cow elk requirements only in early fall (2750 kcal · kg -1 ). Sodium levels never exceeded about 10% of the required 600 μg · g -1 . The potential for maintaining a relatively high density of elk at forage-quality levels that fulfill requirements declines as summers progress on Great Basin summer ranges. Maintaining highly productive elk herds in the Great Basin requires that managers maintain plant communities with a diversity of forbs, grasses, and browse to provide for nutritional needs of lactating cows and their growing calves.     

Structure of alpine plant communities near King's Peak, Uinta Mountains, Utah

A study was made at 18 sites with elevations between 3512 and 3768 m in the Uinta Mountains, Utah. Sites were small in extent but typified vegetation patterns found in the Uintas. Standing crop, species composition (based on dry weight), and values for several physical parameters were determined at each site. Simple linear regressions performed between the various biotic and abiotic characters revealed significant relationships between the characteristics of rocks visible at the surface (the number, size, and variation in size) and vegetation cover. This relationship was probably due to the burial of rocks as a region became vegetated. Bray and Curtis ordinations performed on the data indicated that there were several factors which influenced the species composition but that no single factor dictated the vegetational pattern.     

Population structure and ecological effects of the crayfish Pacifastacus leniusculus in Castle Lake, California

The recent appearance of the ""California crayfish,"" Pacifastacus leniusculus , in Castle Lake, California, and interest in its potential impacts on the lake ecosystem provided motivation for a study of the population structure and habitat use of this species and its effects on aquatic macrophytes. Mark-recapture studies indicated that the total number of adult (3 + yr or older) crayfish in the lake was ca 10,100 individuals, yielding an estimate of lakewide crayfish density in preferred crayfish habitats of 0.13 adults m -2 . Using mean body mass of individuals, we estimated that ambient biomass density was 5.9 g m -2 . Length-weight relationships determined for captured individuals were sex dependent, with males having greater body mass for a given carapace length. Length-frequency and weight-frequency diagrams indicated that P. leniusculus reaches larger sizes in Castle Lake than do populations of P. leniusculus in ultraoligotrophic Lake Tahoe. Population-wide, males were significantly larger in both carapace length and body mass than females. We also examined sex dependence of interhabitat differences in crayfish body size by comparing animals trapped in rocky areas with those from areas with macrophytes and soft sediments. No significant differences in overall body size were found between habitats, but a significant habitat-sex interaction term occurred because the sex-dependent size differences were more pronounced in sediment than in rocky areas. Exclosure and enclosure experiments indicated that crayfish had large but differential impacts on Castle Lake macrophyte species, as the abundance of two of the dominant species ( Chara sp., Potamogeton richardsonii ) declined in the presence of crayfish and, in one case, increased in exclosures. These effects occurred via both consumptive and nonconsumptive mechanisms. These studies indicate that and expanding population of P. leniusculus in Castle Lake may be producing sizable impacts on the littoral zone habitat.     

Similarity between pronghorn and mule deer fecal pellets

Botanical compositions and pH values for pronghorn ( Antelocapra americana ) and mule deer ( Odocoileus hemionus ) fecal pellets from the Idaho National Engineering Laboratory Site were different. As there was no overlap between ranges of the herbivores fecal pH values, the fecal pH technique is a valuable tool for distinguishing between fecal pellets of pronghorn and mule deer on the study area.     

New records of Scolytidae from Washington state

Eighteen species of Scolytidae are reported from Washington state for the first time or raised from obscurity: Scierus annectens LeConte, Hylesinus californicus (Swaine), Phloeotribus lecontei Schedl, Carphoborus vandykei Bruck, Polygraphus rufipennis (Kirby), Crypturgus borealis Swaine, Pityogenes knechteli Swaine, Ips mexicanus (Hopkins), Ips perturbatus (Eichhoff), Ips plastographus plastographus (LeConte), Ips woodi Thatcher, Trypodendron betulae Swaine, Trypophloeus striatulus (Mannerheim), Procryphalus mucronatus (LeConte), Procryphalus utahensis Hopkins, Pseudopityophthorus pubipennis (LeConte), Pityophthorus alpinensis G. Hopping, and Pityophthorus grandis Blackman. Host tree and collection data are given for these species. A total of 105 scolytid species known from Washington are listed.     

Endangered, threatened, extinct, endemic, and rare or restricted Utah vascular plants

The status of 382 vascular plant taxa with distribution in Utah is presented. Some 66 species are possibly endangered, 198 threatened, 7 extinct, and 20 extirpated within the state; 4 species have questionable taxonomic status. Included in the list are nearly 225 species of endemic plants, many of which are among the possibly endangered, threatened, and extinct or extirpated plants. Bibliographic citations, type locality, status, and distribution by counties is included for each species or infraspecific taxon. Two new species are described: Psoralea pariensis and Eriogonum natum. One new name, Astragalus barnebyi, is proposed; and one new variety, Eriogonum umbellatum var. deserticum, is proposed. The following new combinations are made: Cycladenia humilis var. jonesii; Aralia racemosa ssp. bicrenata; Heterotheca jonesii; Hymenoxys depressa; Xanthocephalum sarothrae var. pomariense; Thelypodium integrifolium var. complanatum; Thelypodium sagittatum var. ovalifolium; Arenaria kingii var. plateauensis; Psorothamnus thompsonae; Najas caespitosus; Oenothera gouldii; Eriogonum corymbosum var. revealianum; Penstemon humilis var. obtusifolius; Penstemon lentus var. albiflorus; and Viola purpurea var. charlestonensis.       

Occurrence of the musk ox, Symbos cavifrons, from southeastern Idaho and comments on the genus Bootherium

Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 st1\:*{behavior:url(#ieooui) } /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} A set of ovibovine horn cores collected from Pleistocene sediments in southeastern Idaho provides additional evidence for sexual dimorphism in the helmeted musk ox, Symbos cavifrons. Specimens previously assigned to Bootherium sargenti are placed in synonomy with Symbos cavifrons as sexual dimorphs (females). Bootherium bombifrons is a valid taxon and is probably not closely related to Symbos.     

Dam-site selection by beavers in an eastern Oregon basin

We compared physical and vegetative habitat characteristics at 14 dam sites occupied by beaver ( Castor Canadensis ) with those at 41 random unoccupied reaches to identify features important to dam-site selection in the Long Creek basin, Grant County, Oregon. Stream reaches with dams were shallower and had a lower gradient than unoccupied reaches. Beaver did not build dams at sites with a rock substrate. Bank slopes at occupied reaches were not as steep as those at unoccupied reaches; and occupied stream reaches had greater tree canopy cover, especially of thinleaf alder ( Alnus tenuifolia ), than did unused reaches. A discriminant model using transformations of bank slope, stream gradient, and hardwood cover classified all beaver dam sites correctly and 35 of 41 random sites as unoccupied sites. The 6 misclassified sites had rock substrates. We also tested four habitat suitability models for beaver in this basin. Three models produced significantly different ( P < .05) scores between occupied and random unoccupied reaches, suggesting that they might have some utility for this region.     

High nitrogen availability does not improve salinity tolerance in Sarcobatus vermiculatus

Natural and anthropogenic changes in basin lake levels in the western U.S. expose saline, alkaline substrates that are commonly colonized by shrubs in the Chenopodiaceae. On a chronosequence of recently exposed substrates at Mono Lake, California, Sarcobatus vermiculatus has greatest biomass accrual, seed production, seedling establishment, and leaf N at younger sites where soils are extremely saline and alkaline. These field observations and an understanding of the role of N-containing compatible solutes in salinity tolerance of halophytes led to our prediction that Na and N interactions stimulate Sarcobatus performance. To test this, we grew Sarcobatus juveniles for 2 years in the greenhouse at 4 levels of NaCl (5, 100, 300, and 450 mM) and 3 levels of N (0.04, 0.4, and 8 mM) in a randomized, complete-block design. Contrary to our expectations, high N availability did not induce salt-stimulated growth nor did it increase salinity tolerance in Sarcobatus . Increased N nutrition also had no significant effect on leaf cation ratios or selectivity. Plants grown at high salinity had significantly lower leaf K:Na, Ca:Na, and Mg:Na ratios than plants grown at lower salinity. However, plant selectivity for the macronutrient cations remained high, even at 450 mM NaCl. Without such high selectivity, the cation nutrition of Sarcobatus would decline to even lower levels, resulting in severe nutrient deficiencies. This study suggests that the ability of Sarcobatus to attain high leaf N, rather than an interaction between Na and N, enhances its performance at saline sites. In addition, the ability of Sarcobatus to maintain high macronutrient cation selectivity despite high salinity allows its distribution to extend to extremely saline and alkaline substrates in this arid system.