Treesearch

The effects of wildfire on tree mortality, stand structure, and regeneration are major concerns in many California ecosystems. These effects are often highly variable across the landscape and can be difficult to assess at broad scales. There are few datasets that provide a detailed description of stand conditions, both before and after wildland fire, particularly in the Coast Redwood forest type. This study provides a unique collection of pre- and post-fire remote sensing data to evaluate the effects of the 2009 Lockheed Fire, a 7,817 ac wildland fire that occurred near Santa Cruz,...

Harvesting in predominantly redwood forests has been ongoing in the Santa Cruz Mountain region for over 150 years. Under California Forest Practice rules specific to the Southern Subdistrict of the Coast District, clearcutting has been outlawed since 1970. Since that time, single tree selection has been the only silvicultural practice allowed in the Southern Subdistrict. Big Creek Lumber Company has been practicing some form of selective harvesting throughout coastal redwood forestlands in the Santa Cruz Mountains since 1946. Sixty-five years of experience makes it is possible to form...

Under present California Forest Practice Rules, mandated by the Legislature and codified by the State Board of Forestry, Non-industrial Timber Management Plans (NTMPs) give small landowners the flexibility to operate under a specific set of rules 'forever,' allowing short notice (3 days or less) for pre-approved harvest operations. This permit is presently restricted to forestland ownerships less than 2,500 acres, requires uneven-aged management (selection harvest), and allows forest managers to both react to market conditions and have certainty of regulation. There is no comparable tool...

There are approximately 513,000 acres of coniferous forests and oak woodlands in Sonoma County, California, situated about 50 miles north of San Francisco. Most of the oak woodland, and over 68 percent (132,000 acres) of the coniferous forestland, is in private ownerships of 50 acres and less. These forests are unique, with 10 species of true oak and 19 species of conifer in the county. While Sonoma's forests provide a suite of benefits, factors create pressure to parcelize, convert to viticulture, and fragment the forest ecosystem. In order to address these threats, an ad-hoc committee...

New Zealanders are making a significant effort to develop their forest industry to benefit from rapid growth exhibited by Sequoia sempervirens on both the North Island and South Island. US and New Zealand forest products companies have established redwood plantations in the past decade, and have found that microclimate, site preparation, soil chemistry, fertilization and precise silvicultural practices are all of utmost importance. Farm foresters have established experimental redwood tree crops alongside Pinus radiata and many other western US and NZ native species. The NZ Farm Forestry...

Families or family businesses own nearly all of the private redwood forestland in California. Family forest owners have practiced both subdivision and silviculture for decades but the dominant theme for most family owners is environmental stewardship. Parcel size is more important than expressed values as a predictor of resource management activities. All landowners with more than 50 acres undertook high levels of resource stewardship regarding controlling invasive species, protecting water quality, improving fish and wildlife habitats, and removing individual trees to promote forest...

Airborne Light Detection and Ranging (LiDAR) holds promise to provide an alternative to traditional ground-based survey methods for stream channel characterization and some change detection purposes, even under challenging landscape conditions. This study compared channel characteristics measured at 53 ground-surveyed and LiDAR-derived crosssectional profiles located in six study reaches of Little Creek, a forested headwater stream on Cal Poly’s Swanton Pacific Ranch, near Santa Cruz, CA. Three LiDAR datasets were compared in this study, with flights in 2002, 2008, and 2010, a period of...

In this study, height-diameter equations were developed for managed stands of coastal redwood/Douglas-fir stands in Mendocino County. Equations were developed by species to predict tree height as a function of diameter as well as other factors that are known to potentially explain tree height, including site class and live crown ratio. Two equation forms were compared and evaluated. Forest inventory data from Jackson Demonstration State Forest were used to fit the equations. These height-diameter equations will be useful in explaining height-diameter relationships in largely uneven-aged...

The landscape genetics framework is typically applied to broad regions that occupy only small portions of a species' range. Rarely is the entire range of a taxon the subject of study. We examined the landscape genetic structure of the endangered Point Arena mountain beaver (Aplodontia rufa nigra), whose isolated geographic range is found in a restricted (85 km2) but heterogenous region in California. Based on its diminutive range we may predict widespread gene flow and a relatively weak role for landscape variation in defining genetic structure. We used skin, bone, tissue and noninvasively...

In 2002, the Williams Fire burned >90 % of the San Dimas Experimental Forest, providing an opportunity to investigate differences in soil water repellency, peak discharge, and sediment yield between grass-converted and chaparral watersheds. Post-fire water repellency and moisture content were measured in the winter and summer for four years. Peak discharge was determined using trapezoidal flumes with automated stage-height recorders. Sediment yields were measured by making repeated sag-tape surveys of small debris basins. Other than the high summer 2005 increase in repellency on the grass...