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To address uncertainty in the performance of seedlings planted in and around postburn substrates, we systematically planted seedlings in the center of, on the edge of, and outside ash substrate footprints following burning of logging residue piles and monitored growth and survival for a decade. Five species (Douglas-fir [Pseudotsuga menziesii], giant sequoia [Sequoiadendron giganteum], incense-cedar [Calocedrus decurrens], sugar pine [Pinus lambertiana], and ponderosa pine [Pinus ponderosa]) were planted in a regenerating mixed-conifer stand in the Sierra Nevada range of California. There was a positive effect of ash substrate proximity on growth that was immediate and persisted for 10 years for every species except incense-cedar. Seedlings planted in the centers of ash substrates consistently outgrew (in both height and basal diameter) seedlings that were planted either on the edges of or outside ash substrates. Douglas-fir had the greatest height gain (+47%), followed by giant sequoia (+28%), sugar pine (+23%), and ponderosa pine (+17%). Basal diameter differences were similar. No effect of ash proximity on survival was detected. Planting seedlings in the centers of ash substrates led to exceptionally larger trees by the time the stand had developed enough to apply a precommercial thin, a relevant milestone for managed stands.

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Lakes provide important habitat for salmonids that may use them as a primary feeding area between periods of reproduction. The seasonal changes in vertical thermal structure in lakes can affect the distribution of salmonids on seasonal and diel time scales as they search for, consume, and digest prey that also exploits the water column's distribution of food, temperature and light. Our goal was to analyse the vertical distribution of wild, native coastal cutthroat trout (Oncorhynchus clarkii clarkii) in Lake Washington on daily and seasonal time scales. This lake is stratified in the summer and isothermal in winter, allowing us to compare vertical movements between periods with and without thermal structure in water 50 m deep. We predicted that trout would be deeper in the water column during stratified months and shallower during isothermal months, and shallower at night than in the day. Overall, the trout showed these patterns in the depths and temperatures they occupied, tending to be within or below the thermocline in the summer but not in the coolest water available, and closer to the surface when the lake was isothermal. The trout were also closer to the surface at night and deeper during the day. The vertical range of these diel movements shifted with the seasons–deepest in October, as the thermocline deepened and weakened, and shallowest in January when the lake was isothermal. These seasonal and diel vertical distribution patterns by the trout optimise metabolism for growth, and facilitate feeding on planktivorous fishes that also show seasonal and diel vertical distribution changes.

No abstract