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Summary: A new genus and species of anguinid nematode, Cotylenchus cleo gen. n., sp. n., was recovered from leaves of the western sword fern, Polystichum munitum , growing in rainforests in several locations of Olympic National Park, Washington State, USA. This new anguinid nematode induced distinct necrotic and chlorotic symptoms on fern leaves characterised by yellowing, light to brown areas between veins. The new species is characterised by a long and slender body, six incisures in the lateral field, robust stylet (12.0-13.5 μ m) with large and rounded knobs, pyriform to elongate and abutting basal pharyngeal bulb, and long conical tail with pointed terminus; females having posteriorly located vulva (V = 74-80%) and well-developed post-vulval uterine sac (26-59 μ m) and males having spicules 20-23 μ m long. Phylogenetic analysis of the partial 18S rRNA and the D2-D3 expansion segments of the 28S rRNA genes showed that this anguinid nematode formed a separate evolutionary lineage different from all other Anguinidae taxa. The new species was also characterised by sequencing the ITS rRNA and COI genes. [ABSTRACT FROM AUTHOR]

Context: Western Olympic valley bottoms, disturbed by alluvial processes, are dominated by Picea sitchensis and isolated cohorts of Pseudotsuga menziesii, while upland contexts, disturbed by wind and fire, are dominated by P. menziesii. These forests have distinct structure and produce large trees with habitat for endangered birds. Objectives: Describe how disturbance and forest development create landscape forest patterns and distribution of large trees in valley bottom and upland forests. Methods: LiDAR data of ~ 9700 ha within Olympic National Park, USA was classified based on vegetation height and percent cover to contrast valley bottom and upland forests. Within-crown structure from 36 P. sitchensis and 12 P. menziesii was then used to predict locations of the largest and most complex trees. Results: Valley bottoms comprise small patches of dense tall (11%), medium-height trees (19%), and gaps (7%) embedded in open-canopy forest with scattered tall trees (63%). Upland forests comprise larger patches of tall (16%), medium (58%), and open-canopy forest (25%) with few gaps (1%). The largest trees are more abundant in valley bottoms (0.05 tree ha−1) than upland (0.02 tree ha−1) due to small patches of tall trees within open-canopy forest. Conclusions: Alluvial disturbance, fungi-wind interaction, and dominance of late-successional fast-growing P. sitchensis create open-canopy forest with more large trees, while severe fire and wind interacting with P. menziesii create patchy closed-canopy forest with fewer large trees. Management for large habitat trees should use aggregated retention with P. menziesii, multi-aged selection techniques with P. sitchensis, and indefinitely retain a low density of large trees. [ABSTRACT FROM AUTHOR]

The article explores the mission of Gordon Hempton of Olympic National Park to record the natural sounds of the world before they are drowned out by human noise in the rainforest along the Hoh River in Washington. It outlines the "One Square Inch of Silence" campaign established by Hempton, which aims to protect the silence of the national parks. Moreover, it mentions the widest diversity of soundscapes discovered by Hempton within the national park system.

Most old fields in the Queers Valley of Olympic National Park, USA, remain dominated by exotic herbs 60 y after abandonment although the fields are surrounded by temperate rain forest. However, areas of some fields have been invaded by Picea sitchensis, one of three dominant forest species (with Alnus rubra and Tsuga heterophylla). This provided an opportunity to examine local variation of factors (competition, facilitation, cervid herbivory, soils) that influence tree colonization within a set of old fields, an approach rare in previous studies. Picea sapling invasion of field edges was negatively correlated with percent cover of Agrostis gigantea and positively correlated with Anthoxanthum odoratum. Potential indicators of competition (sod thickness, thatch thickness, percent ground cover) were correlated with Agrostis cover, Picea edge invasion was also correlated with soil organic matter. In experiments, seedlings of Picea and Tsuga emerged as readily in Agrostis as in Anthoxanthum or Pteridium aquilinum, but suffered higher mortality in Agrostis. Experimental seedling establishment was low and required reduction of competing vegetation. In experiments with transplanted seedlings, cervid herbivory suppressed growth of Tsuga and Alnus, but not Picea. Growth of Picea seedlings was facilitated by Pteridium. Differential tree colonization of the fields resulted from: (1) differential competition by invaded cover types against seedling establishment, (2) selective herbivory on tree species of established seedlings and (3) facilitation by fern cover of seedlings of an unbrowsed species. [ABSTRACT FROM AUTHOR]

Although mountainous landscapes dominate large areas of the Earth, our understanding of how elevation and aspect influence soil respiration in complex mountainous terrain is very limited. Therefore, we measured soil respiration throughout the growing season in 1999 and 2000 at 11 forested sites in Olympic National Park, Washington, USA along elevation-climatic gradients. The study sites ranged from temperate rain forest to alpine forests near tree line. Soil temperature was a significant predictor of soil respiration at all sites, and soil moisture explained additional variability at three sites (R2 from 0.42 to 0.90, P ≤ 0.01). Soil temperatures at the highest-elevation sites were 4.5°C cooler than those at the lowest elevation, but there were no relationships between soil respiration rates at a given temperature and elevation or mean annual temperature that would indicate acclimation of soil respiration to the cooler temperatures at high-elevation sites. Experimental urea additions (1.0 and 2.0 g N m-2 y-1) made at seven of the sites had no consistent effect on soil respiration. Total soil carbon dioxide (CO2) efflux during the growing season (May–September) varied from 0.34 to 0.75 kg C/m2 and was greater at low-elevation site s wit h warmer soil temperatures and longer growing seasons. Elevation and the length of the frost-free season could both be used to predict growing season (r2 = 0.53) and annual (r2 = 0.81) soil CO2 efflux for the 10 sites located in sleep mountainous terrain. Significant correlations also existed with mean annual temperature. These results suggest that warmer soils and a longer snow-free season associated with climatic warming could cause the mountainous ecosystems of the Olympic peninsula to evolve increasing amounts of CO2 from all elevations and aspects. [ABSTRACT FROM AUTHOR]