We documented settling patterns for territorial males of four species of Neotropical bird species in three riparian study areas in western Montana in 1968, 1980 and 2008. The species were Hammond's Flycatcher (Empidonax hammondii), Warbling Vireo (Vireo gilvus), American Redstart (Setophaga ruticilla), and MacGillivray's Warbler (Geothlypis tolmiei). Early arriving males selected areas with some different vegetation attributes than later-arriving males. The most important vegetation variables in early territories were riparian width, red-osier dogwood (Cornus stolonifera) canopy cover, and red-osier dogwood height. Habitat in territories had some vegetation attributes different than unoccupied areas. Unoccupied habitat had narrower riparian width, taller conifer canopy cover, and shorter dogwood canopy cover.

Native Americans used fire to maintain prairies in western Washington, but few prairies remain due to land-use conversion and forest encroachment. We describe the process of forest encroachment on former western Washington prairies. We used 1853–1871 General Land Office Survey data to describe the historical prairie and associated timbered area conditions at six Joint Base Lewis-McChord sites (JBLM). We described modern stands growing in these same areas with stem density, Reineke stand density index (Reineke 1933), and site index. After harvesting selected trees we measured decadal tree-ring increments and analyzed trauma rings on 242 Douglas-fir stumps to reconstruct stand development. We plotted individual tree stem diameter growth curves to illustrate patterns of establishment. Douglas-fir density increased in waves from 1878–1938 associated with low-intensity fires with fire return intervals of 10 to 91 years. Historical tree density, which ranged from < 1 to 49 trees ha^-1 has increased to 122 to 207 trees ha^-1. Stand development was driven by fires, patterns of establishment, and site potential. Longer fire-free intervals resulted in few larger establishment waves while frequent shorter intervals resulted in multiple smaller cohorts. Woodlands, not prairies, resulted from ten or more year fire frequencies; however, mature forests grew in < 50 years suggesting fire frequencies appropriate for restoration of prairies and woodlands. Modern productive sites produced larger trees that experienced inter-tree competition, suggesting faster forest succession occurred on those sites. Light to moderately thinned Douglas-fir reproduced poorly on our sites. Higher intensity thinning or gap creation may be required for successful regeneration.

The purpose of this research was to examine the effects of pruning and thinning on the growth and mortality of young Douglas-fir (Pseudotsuga menziesii [Mirb] Franco) stands on high-productivity sites in coastal British Columbia. To accomplish this, a two-way randomized incomplete block design with two blocks was established on a coastal site with three levels of thinning (no thinning, thin to 500 stems per ha, and thin to 250 stems per ha) and three levels of pruning (no pruning, prune 250 stems per ha, and prune all trees). The response variables of interest were diameter at breast height (dbh), height, basal area, total and merchantable volume, mortality, damage, and deformities. Dbh and height were examined both for all trees and for only the largest 250 sph by dbh trees (the crop trees). The dynamics in partially pruned stands were also examined. We found that only dbh, basal area, total and merchantable volume, and mortality were affected by thinning. Pruning did not have any effect on the response variables. The pruned trees in unthinned plots and the unpruned trees in thinned plots had a competitive advantage over unpruned trees in unthinned plots and pruned trees in thinned plots, respectively.

Significance: Applying a partial pruning silviculture treatment with the objective of reducing treatment costs by pruning only the minimum number of trees for full site utilization at the end of a rotation did not effectively target the crop trees 20 years after treatment in either thinned or unthinned stands.

Manayunkia speciosa is the obligate invertebrate host of Ceratonova (syn Ceratomyxa) shasta (Myxozoa), the parasite that causes ceratomyxosis (enteronecrosis) in salmon and trout. High peak discharge has been correlated with reduced ceratomyxosis in salmon hosts but how it may influence parasite dynamics in the invertebrate host is unknown. We sampled M. speciosa populations from three sections of the Klamath River, California, in spring and summer months in 2006, a water year that was characterized by i) winter and spring discharge equivalent in magnitude to a 10 year flood and ii) low risk of ceratomyxosis for salmon. M. speciosa were observed in all river sections and months but densities were highest in the upper section, where peak discharge was lowest. Populations were dominated by immature individuals in all river sections and months, followed by progeny and mature individuals. Prevalence of C. shasta infection was 0.25% (SE 0.09) in June; 0.13% (SE 0.09) in July; 0% (SE 0) in August, and 0.03% (SE 0.02) in September. This study provides baseline data on the density and size structure of M. speciosa populations and the prevalence of C. shasta infection following a high magnitude flood event. We discuss the results in the context of using flow manipulation as a tool for managing ceratomyxosis.

Often overlooked, zoosporic fungal parasites of phytoplankton (‘chytrids’) are present in aquatic systems worldwide. Although extensive studies in lakes give insight into potential impacts of chytrid epidemics on phytoplankton blooms and organic matter cycling, the ecological significance of chytrid infections of phytoplankton is still poorly understood in lotic systems. Here, we report the first observations of chytrid parasites attached to multiple diatom species in the lower Columbia River. We isolated a chytrid parasite of the dominant spring bloom diatom, Asterionella formosa, and sequenced DNA from several regions within the ribosomal RNA gene. We also investigated the specificity of the A. formosa chytrid to host and non-host diatoms with isolated cultures and found no cross infection at the species level. In the Columbia River, alterations in the hydrograph following the installation of hydroelectric dams may have opened a niche for chytrid parasites. Greater retention times may allow diatoms to bloom and provide a prolonged interaction period whereby chytrid parasites are able to infect hosts. Future research is needed to assess the seasonality and severity of chytrid infections on diatoms in the lower Columbia River and to evaluate the potential role of zoosporic fungi in influencing the food web structure and biogeochemical cycling in river systems.

Removal of invasive plants to restore native community structure and function is an important component of riparian management in the Pacific Northwest, USA. However, little is known about the role of habitat factors and species' traits in mediating recovery of native riparian systems following removal of invasives. We experimentally investigated the response of riparian understories to removal of Bohemian knotweed (Polygonum x bohemicum). We measured abundance, diversity, and composition of herbaceous and woody species before and for two years after removal. Knotweed removal resulted in rapid and abundant colonization of native woody species and of native and non-native forbs. Variation in the responses of these groups was most commonly associated with two habitat factors, height above channel and depth of knotweed litter. Knotweed litter benefited native forbs (predominantly forest perennials) relative to non-native forbs (predominantly light-demanding annuals). Natives, which are adapted to natural burial by canopy litterfall, showed a neutral response to litter depth, but non-natives showed a negative response. These results illustrate that knotweed removal can be highly effective in initiating riparian understory recovery. The conditions under which post-removal legacies of invasive species can improve native community recovery is a fertile area for research and speaks to the importance of understanding the ways in which species' traits can influence management outcomes.