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Mariposa Woodland Oak Habitat Enhancement Project <br /> Summary <br /> This document outlines a pilot project proposed to enhance an imperiled oak savanna remnant near <br /> Spencer Butte through removal of competing Douglas -firs and some smaller oaks. The objectives are <br /> to reduce fire danger, relieve the white oaks from conifer competition, restore light conditions to the <br /> herbaceous grass /forb community currently being shaded, create downed wood/standing snag habitat <br /> for wildlife, and to gain experience in methods of oak savanna habitat management. The 5 acre site is <br /> located on the north edge of Spencer Butte Park. It spans a property boundary with an adjacent park <br /> neighbor who has also been working to improve oak habitat and reduce fire danger on her property. <br /> These areas are shown on the Vicinity Map and Site Map. <br /> The restoration work will include thinning small oak and fir trees, and then "jackpotting" them or <br /> creating numerous small piles covered with wax paper which dry out over the summer and then are <br /> burned in November once the rains have started and there is little risk of fire escaping. Some material <br /> will be left as downed wood or standing snag material to serve as habitat for wildlife. <br /> Background <br /> The City of Eugene Parks and Open Space Division owns and is responsible for managing hundreds of <br /> acres of upland prairie and oak savanna habitat, predominantly in the Ridgeline Park system of the <br /> South hills but also in a few other smaller sites around town. A significant portion of this upland <br /> habitat includes Oregon white oak savanna, which according to a 1995 USGS report, is among the 21 <br /> most endangered ecosystems in the US. Less than 1% of this habitat remains in the Willamette Valley <br /> from pre- European settlement times, and 98% of this remaining acreage is in private ownership. <br /> Additionally as many as 200 species have been reported to depend wholly or partially on Willamette <br /> Valley oak habitat or upland prairie, including 45 species designated at -risk by USFWS or the State of <br /> Oregon. <br /> Oak savannas and oak woodlands are imperiled for various reasons including conversion of land to <br /> development and agriculture, fire exclusion, and invasive exotic vegetation. Native Americans <br /> reportedly maintained the ecosystem type through frequent low- intensity fires. In the absence of that <br /> fire regime, oak habitat is being shaded out by less fire resistant but faster growing conifers. Without <br /> active management of this fir encroachment, conifers will likely prevail over Oregon oak on all but the <br /> driest sites. Additionally the denser stands of oak and encroaching fir are at an increased risk of <br /> catastrophic fire, so that managing for oak habitat by thinning the oaks and conifers provides greater <br /> fire safety in the long term. <br /> 1 <br />