| genetic variation in chloroplast and nuclear ribosomal dna in utah juniper (juniperus osteosperma, cupressaceae): evidence for interspecific gene flow. | geographic patterns of genetic variation in chlorolast (cpdna) and nuclear ribosomal (nrdna) dna were examined to test the hypothesis of hybridization between juniperus osteosperma and juniperus occidentalis in the great basin of western nevada. noncoding dna from the trnl-trnf intergenic spacer and the trnl intron of the chloroplast genome was sequenced from seven populations of j. osteosperma and four populations of j. occidentalis sampled over a large proportion of their respective ranges. an ... | 2000 | 10675313 |
| antimicrobial activity of some pacific northwest woods against anaerobic bacteria and yeast. | extracts of woods commonly used for animal bedding were tested for antimicrobial activity. essential oils from alaska cedar (chamaecyparis nootkatensis), western juniper (juniperus occidentalis) and old growth douglas fir (pseudotsuga menziesii) as well as methanol extracts of wood from these trees plus western red cedar (thuja plicata) and ponderosa pine (pinus ponderosa) were tested for antimicrobial activity against anaerobic bacteria and yeast. the test microbes included fusobacterium necrop ... | 2001 | 11746838 |
| gas exchange and carbon isotope discrimination of juniperus osteosperma and juniperus occidentalis across environmental gradients in the great basin of western north america. | we determined how ecophysiological characteristics of two juniper species, juniperus occidentalis hook. (western juniper) and juniperus osteosperma (torr.) little (utah juniper), changed along altitudinal and regional environmental gradients in the great basin of western north america. we obtained diurnal measurements of leaf gas exchange and xylem water potential (psi) from plants at a low and a high altitude site within each of six mountain ranges during fall 1994, spring, summer, and fall 199 ... | 1999 | 12651548 |
| toxicity studies on western juniper oil (juniperus occidentalis) and port-orford-cedar oil (chamaecyparis lawsoniana) extracts utilizing local lymph node and acute dermal irritation assays. | the essential oil extracts of western juniper oil (juniperus occidentalis) and port-orford-cedar oil (chamaecyparis lawsoniana) were evaluated for possible dermal toxic effects on mice and rabbits. mice were tested for their response to both extracts utilizing a local lymph node assay. western juniper oil extract at 0.5% and 5% concentrations did not show a stimulation index (si) greater than normal (3.0); however, a 50% concentration did show a positive response at 3.3. port-orford-cedar oil ex ... | 2004 | 15501613 |
| biocidal activity of three wood essential oils against ixodes scapularis (acari: ixodidae), xenopsylla cheopis (siphonaptera: pulicidae), and aedes aegypti (diptera: culicidae). | the biocidal activity of three steam distilled wood essential oils-incense cedar, calocedrus decurrens (torr.) florin; port-orford-cedar, chamaecyparis lawsoniana (a. murr.) parl.; and western juniper, juniperus occidentalis (hook)--were evaluated against adult aedes aegypti (l.) (diptera: culicidae) and xenopsylla cheopis (rothchild) (siphonaptera: pulicidae) and nymphal ixodes scapularis say (acari: ixodidae). in vitro laboratory bioassays were conducted to establish baseline dose-mortality da ... | 2007 | 17461093 |
| shrub-steppe early succession following juniper cutting and prescribed fire. | pinus-juniperus l. (piñon-juniper) woodlands of the western united states have expanded in area nearly 10-fold since the late 1800's. juniperus occidentalis ssp. occidentalis hook. (western juniper) dominance in sagebrush steppe has several negative consequences, including reductions in herbaceous production and diversity, decreased wildlife habitat, and higher erosion and runoff potentials. prescribed fire and mechanical tree removal are the main methods used to control j. occidentalis and rest ... | 2011 | 21344252 |
| western juniper management: assessing strategies for improving greater sage-grouse habitat and rangeland productivity. | western juniper (juniperus occidentalis subsp. occidentalis) range expansion into sagebrush steppe ecosystems has affected both native wildlife and economic livelihoods across western north america. the potential listing of the greater sage-grouse (centrocercus urophasianus) under the u.s. endangered species act has spurred a decade of juniper removal efforts, yet limited research has evaluated program effectiveness. we used a multi-objective spatially explicit model to identify optimal juniper ... | 2015 | 25957623 |
| restoration of mountain big sagebrush steppe following prescribed burning to control western juniper. | western juniper (juniperus occidentalis ssp. occidentalis hook) encroachment into mountain big sagebrush (artemisia tridentata spp. vaseyana (rydb.) beetle) steppe has reduced livestock forage production, increased erosion risk, and degraded sagebrush-associated wildlife habitat. western juniper has been successfully controlled with partial cutting followed by prescribed burning the next fall, but the herbaceous understory and sagebrush may be slow to recover. we evaluated the effectiveness of s ... | 2014 | 24573166 |
| vegetation response to western juniper slash treatments. | the expansion of piñon-juniper woodlands the past 100 years in the western united states has resulted in large scale efforts to kill trees and recover sagebrush steppe rangelands. it is important to evaluate vegetation recovery following woodland control to develop best management practices. in this study, we compared two fuel reduction treatments and a cut-and-leave (cut) treatment used to control western juniper (juniperus occidentalis spp. occidentalis hook.) of the northwestern united states ... | 2013 | 23811771 |
| acute aquatic toxicity of western juniper (juniperus occidentalis) foliage and port orford cedar (chamaecyparis lawsoniana) heartwood oils. | recently, interest has developed for using essential oils from western juniper (juniperus occidentalis) foliage and port orford cedar (chamaecyparis lawsoniana) heartwood in commercial products such as pest repellents and cosmetics. in order to gauge the relative toxicological risk that these oils pose to freshwater and marine organisms, the acute aquatic toxicity of these oils was evaluated using oppts guidelines to the cladoceran daphnia magna, the rainbow trout oncorhynchus mykiss and the gre ... | 2010 | 20033284 |