Treesearch

During a period of unusually hot, dry weather in 1972, the Creighton Ridge fire burned 4,452 ha (11,000 ac) of forest and intermixed grasslands, as well as many residences on the recently-subdivided 16 ha (40 ac) ranch holdings in the Cazadero – Fort Ross area, north of San Francisco. In response to the fire, local work crews planted and thinned trees from 1981 to 2000 with State of California economic and technical assistance. Plantations of ponderosa pine (Pinus ponderosa Douglas ex C. Lawson) and Coulter pine (Pinus coulteri D. Don) were to serve as ‘nurse trees’ allowing ingrowth of...

Models predicting future climates and other kinds of information are being developed to anticipate where these two species may fail, where they may continue to thrive, and where they may colonize, given changes in climate and other elements of the environment. Important elements of such predictions, among others, are: photoperiod; site qualities; changes in levels and yearly patterns of temperature, wind, fog and precipitation; the effects of these on interactions with other biota at each site; the effects of changes in fire frequency and intensity; the availability of seeds and seed...

We describe the foundation, objectives, and initial results from a stand-level experiment focused on restoration of redwood (Sequoia sempervirens (D. Don) Endl.) forests impacted by sudden oak death (SOD), caused by Phytophthora ramorum. Our study stands were primed for heavy impacts by SOD. Extensive harvesting which ended circa 1910 on Mt Tamalpais (Marin County, California) resulted in high densities of tanoak trees with interspersed residual redwood. The arrival of P. ramorum and subsequent emergence of SOD transformed these stands into tanoak shrublands with interspersed redwood...

The Humboldt marten (Martes caurina humboldtensis) historically occurred in California’s coastal redwood (Sequoia sempervirens (D. Don) Endl.)-dominated forests from northern Sonoma County, California to the Oregon border. The subspecies was thought to be extirpated due to over-trapping and loss of habitat until a small, remnant population was rediscovered in 1996 on the Six Rivers National Forest (Slauson, personal communication). Surveys conducted from 2004 to 2011on managed forests owned by Green Diamond Resource Company to the west of the remnant population yielded marten detections at...

Highway construction of the Redwood National Park bypass resulted in a storm-driven accidental infusion of exposed sediments into pristine streams in Prairie Creek Redwoods State Park, California in October 1989. We evaluated impacts of this ecosystem stress on three amphibians, larval tailed frogs (Ascaphus truei), coastal giant salamanders (Dicamptodon tenebrosus), and southern torrent salamanders (Rhyacotriton variegatus), by comparing densities by mesohabitat type in five sediment-impacted with five unimpacted streams. Impacted streams had six-fold higher pool bowl sediment loads and...

Crowns of old redwoods (Sequoia sempervirens (D. Don) Endl.) are teaming with life. Storm damage followed by recovery via trunk reiteration increases the structural complexity of redwood crowns over time. Bark and wood surfaces within complex redwood crowns accumulate debris and become covered with epiphytes. Arboreal soils develop beneath mats of the leather-leaf fern, Polypodium scouleri, and within pockets of decaying wood colonized by the evergreen huckleberry, Vaccinium ovatum, promoting water storage and allowing desiccation-sensitive creatures to flourish high above the ground....

Documenting species distribution patterns and habitat associations is a necessary prerequisite for developing conservation measures, prioritizing areas for habitat restoration, and establishing baseline conditions for long-term monitoring programs. The coastal tailed frog (Ascaphus truei) ranges from coastal British Columbia to northwestern California and is one of several species of co-occurring amphibians that breed in cold headwater streams. Several accounts of tailed frog distribution suggest that the species’ range has been unchanged during the age of industrial timber harvesting....

Precommercial thinning is an important tool for coast redwood (Sequoia sempervirens (D Don) Endl.) forest management but is often followed by black bear (Ursus americanus) damage in northern parts of redwood’s natural range (Fritz 1951; Giusti 1988, 1990; Hosack and Fulgham 1998). The bears scrape off bark and feed on the sugar-rich phloem of coast redwood and coast Douglas-fir (Pseudotsuga menziesii var. menziesii (Mirb.) Franco) (Kimball et al. 1998). A prior study at the same study area within the Mill Creek watershed in Del Norte Coast Redwoods State Park, near Crescent City, in Del...

A total of 789 black bear damaged trees were investigate over a multi-year period on 14 different study sites chosen on lands of four participating timber companies. The sites ranged from 30 to 50 years of age. Four different conifer species were found to have black bear damage: coastal redwood (Sequoia sempervirens (D. Don) Endl.), Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco), Sitka spruce (Picea sitchensis (Bong.) Carr.), and western hemlock (Tsuga heterophylla (Raf.) Sarg.). Numerous variables were measured on each black bear damaged tree (diameter at breast height [DBH; 1.37 m],...

Imported forest pests have changed North American forests and caused staggering monetary losses in the centuries since the country was founded. Since most problem-causing non-native pests are innocuous in their home ranges, where they have coevolved with their host trees, experts cannot predict which pathogens or insects will have lethal effect on other continents. Many non-native pests are unknown to science until they cause problems in their new homes. One common response to the threat of non-native insects and diseases in our forests is to appeal to science to develop technical means...