The M9 Sanitation and Salvage Project Is Designed to Meet Multiple Objectives. the First Objective
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M9 Sanitation and Salvage Project Silviculture Report Overall Management Direction: The M9 sanitation and salvage project is designed to meet multiple objectives. The first objective is primarily designed to recover the economic value of salvageable dead trees. Second stands will be sanitized, by means of thinning green trees, to reduce the potential for continued or future western and mountain pine beetle attack, and to increase residual stand resiliency to future stress. This objective will be met by means of thinning green trees to stocking levels low enough to reduce the competition for limiting resources and increasing individual tree growth, thereby reducing the risk of further extensive beetle related mortality (Fettig et al. 2007). These objectives are defined in the Mendocino National Forests Land and Resource Management Plan (LRMP) (USDA, 1995). Sanitation and salvage harvest volume is specifically addressed in the LRMP, p C-3 "Sanitation and salvage volumes from suitable lands are an integral part of the yields anticipated by the Plan ... and they are part of the scheduled Allowable Sale Quantity." This will meet the Management Direction sections in Chapter N (IV p. 2-4) under ''Timber and Other Forest Products: Provide a sustained yield of timber and other wood products to help support local economies and to contribute to meeting local, regional, and national needs." These treatments will also address the Management directions of Forest Health "Provide an integrated pest management program to prevent or control insect and disease outbreaks on forest and rangeland resources ... " Integrated goals of fire and fuels reductions including "Maintain a cost effective detection, prevention, suppression, and fuels management program mix in support of other resource programs." and wildlife "Maintain or improve the diversity and quality of habitat needed to support viable populations of all native and desired non-native wildlife and fish species, providing for consumptive and non-consumptive use at projected demand levels." will also be addressed. This project lies within the North Grindstone Management Area, this area is matrix land, subject to timber management and harvest as described in LRMP Rx 7, Timber Modified. (USDA, 1995 pg. IV -69). This general management prescription provides for emphasis on timber production while providing for other resource objectives including visual quality, watershed, rare and endemic species, and wildlife. The LRMP also states that, "In the long term, control of competing vegetation and the density of conifers through management in plantations and natural stands, will help reduce insect-caused mortality under prolonged drought conditions". (USDA, 1995 p.iii-11). Background: Forest stands occupying the areas around and including the M9 sanitation and salvage project area have been shaped by many of the forces described by Fettig et al. 2006, including altered historic fire regimes through active fire suppression in the recent century, and selective harvest 1 ~ M9 Sanitation and Salvage Project methods. These land management practices have led to overstocked tree densities as a result. These stocking levels have resulted in reduced individual tree vigor within stands as well as in growth of younger trees under the favorable micro-site conditions created by the disturbed canopies. Fire suppression prevented the natural cleaning method for these stands to control stocking levels and recruitment of new trees as well as brush and other woody competition control. As a result these overstocked stands have declined in individual tree growth rates, a key indicator as pointed out by Fettig et al. 2007, of susceptibility to bark beetle attack in ponderosa pine stands in the western US. Data collected in these stands in~icates all stands have individual tree growth rates below the thresholds (periodic annual increment < 0.24 em, 5 year growth rates ~ 0.66cm/yr. etc.) described by Fettig et al. 2007 (p. 27, 29.). This combination of factors created an environment in which beetles easily moved into these stands after a large storm, in the winter of 2010, knocked out and damaged a larger number of overstory ponderosa pine tops. Beetle populations in these larger damaged green boles remaining after the storm in combination with mild winter temperatures, which have reduced the usual mortality of overwintering beetles, and periodic drought coupled with the high tree densities led to more successful broods each year. These factors have led to much larger than normal pockets of pine mortality due to successful bark beetle attacks within stands. These larger populations within stands are now coalescing and overwhelming the weakened defenses of the stressed stands causing extensive stand level pine mortality (See Photo 1 & 2. ). These stands are located on the top third of south and west facing ridges between 4200 and 5400 feet in elevation. They are all located on the Sheetiron soil series a Loamy-skeletal, mixed, active, mesic Typic Dystroxerepts (NRCS, 2012). These sites are subject to a Mediterranean climate characterized by cool wet winters, averaging between 35-45 in. of precipitation per year, and hot dry summers with extended periods, 3-5 months, of little to no precipitation. Moisture is the limiting resource for vegetation on these sites and they are characterized by chaparral in the lower elevations 2000-3500 feet elevation, which transitions into oak woodlands with some pine and brush components between 3500-4500 feet elevation, to the ponderosa pine stands located within the project area. Forest cover does extend into the lower elevations in moist areas such as riparian areas and drainages. Ridges, which are where the units are located, are often drier with thinner soils, less tree cover, and lower site index. Due to its drought tolerant nature, ponderosa pine stands such as these occupy the transition zone between non-forested areas of grassland and shrubs to more closed canopy forests such as the sierra mixed conifer stands located on the north facing slopes of Log Springs ridge (Habeck, 1992). Old growth as defined in Potter et al. 1992 was not found in these areas. Based on the numbers collected and analyzed in Table 1, as well as field reviews in each unit to review qualitative attributes, no old growth stands were found within any of the units. 2 M9 Sanitation and Salvage Project Photo 1. Large pockets of beetle mo1tality coalescing into stand level areas of ponderosa pine mortality. The pocket in the smaller circle was over 2 ac. in size. Photo 2. Western bark beetle pitch tubes on a green tree indicating both successful and unsuccessful attacks on a live ponderosa pine in unit 18. 3 M9 Sanitation and Salvage Project Photo 3. Overtopped oak located adjacent to the ponderosa pine in Photo 2. This tree is clearl y overtopped by pines but has enough crown left to likely increase growth and vigor after release from suppressio n. I Silvicultural Prescription: Sanitation/Salvage Timber harvest: o 250 acres of salvage of dead and dying trees as well as sanitation harvest of stands to residual green tree basal areas between 60-80 ft2/ac. (20 ft?/ac. along roads). Specific sil vicultural prescriptions include: • Remove: Focus on ponderosa pine, specifically around current pockets of pine beetle mortality, target the removal of beetle infested (those showing signs of beetle infestation including pitch tubes, frass, or stripped bark) green trees, and any salvageable dead. Around existing western bark beetle pockets remove all (Jive or dead) merchantable ponderosa pine within one tree height of the nearest recently dead ( <1 yr. dead) or currently dying group or individuals. • Remove: trees by focusing on existing dense areas including groups or clumps of trees, especial those located on ridges, south or west facing slopes, or other dry more stressed sites to a target residual basal area of 60-80 ft2/ac. • Remove: all hazard trees - those trees which could result in property damage (FSM 2303; 2330; 6703; 6730), including trees within one tree height of the road -or top trees low enough so they are not able to hit the road if they are to be left as snags. Sanitize road side areas to prevent future hazard trees, if ponderosa pine is a component of the residual stand reduce these roadside areas to a residual green tree basal area of 20 telae. Leave 4 ~ M9 Sanitation and Salvage Project only healthy, vigorous trees, free of damage or other obvious pests, with open grown crowns and a live crown ration of over 40%. Leave all sub-merchantable trees and shrubs within 20' of all cut banks along roads. • Remove: focus on the smallest merchantable trees first leaving around 10-20 ft2/ac. in the 10-16 in. dbh class removing smaller, suppressed, tightly spaced, or otherwise undesirable trees. A residual basal area of 10-20 ft2/ac. should be left in tree between 16- 24 in. dbh removing smaller, suppressed, tightly spaced, or otherwise undesirable trees. The remainder of the target residual basal area should be retained in 24 in. and greater dbh trees with a target residual tree spacing of 40-50 feet after meeting residual basal area requirements. Residual trees generally should be the healthiest, most desirable trees with open grown, high live crown ratio, of the best available phenotypic form (healed mechanical damage such as flat toped defects are acceptable, not phenotypic defects such as y form multiple tops), and the best spatially distributed (evenly spaced for reduced inter-tree competition) trees. • Remove: the heaviest mistletoe infected trees especially any tree located near pockets of reproduction from past disturbance such as existing beetle kill pockets or those areas where snags and other trees have fallen and created gap phase regeneration events. • Retain: all black oaks or large single stem canyon live oaks as residuals and count this basal area in the residual BA. Focus thinning in these areas on removal of conifers especially those which are directly overtopping oaks and also those shading out oak canopies from the side.