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Traditional Clearcutting:
A method no longer used
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Silviculture and Harvesting Methods
(Revised 9/10/2002)
MRC manages its forestlands with a long term goal of restoring the forest to a well-stocked condition with a large variety of sizes and ages of trees. To that end, MRC no longer uses traditional clearcutting as a harvesting method. All harvested stands retain elements that provide perpetual, multi-aged stand structure, and maintain critical ecological refugia (e.g., clumps of standing trees, snags, downed woody debris, undisturbed soil, etc.).
EVEN-AGED MANAGEMENT
The use of even-aged silviculture and harvesting systems on MRC land is viewed as a transitional strategy. Many of the plans MRC files are comprised of both uneven-aged management and even-aged management. Annually, the percentage of acres harvested using even-aged silviculture is 45% and the percentage of acres using uneven-aged silviculture is 55%. Once tanoak-dominated stands are restored to redwood and Douglas-fir dominated stands, the need for even-aged silviculture will be replaced with uneven-aged management across MRC's property.
The California Forest Practice Rules (CFPR) require the Registered Professional Forester (RPF) preparing the plans to designate and describe what cutting prescriptions are to be used in areas proposed for harvest. MRC uses an even-aged harvesting method known as Variable Retention. Variable Retention is not currently a recognized silviculture per CFPR, so when MRC submits plans with Variable Retention silviculture, the forester, by law, has to list the silviculture as "Clearcutting." However, Variable Retention methods differ significantly from traditional clearcutting in that the retention left in place ensures meeting MRC's goal of reestablishing multiple age classes. The following even-aged silviculture prescriptions are used by MRC.
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 Variable Retention: MRC began using Variable Retention as a harvesting method four months after we started in business on the advice of Dr. Jerry Franklin (Professor of Ecosystem Analysis, University of Washington, Seattle, WA) and the Pacific Forest Trust (a regional educational and land-trust organization located in Boonville, CA). Variable retention harvesting retains between 10% and 40% of the original stand (in some cases, more) in both rolling and permanent pockets of untouched trees and critical refugia. This 10-40% of the forest that is retained is composed of tanoaks, Douglas-fir and redwood, as well as other hardwood and conifer species specific to the site. This silviculture regime provides post-harvest ecological structure while creating sufficient opportunity to plant and naturally regenerate redwood and Douglas-fir, as well as restore historical conifer dominance to the forestland. MRC has restricted the use of variable retention silviculture to only our poorly stocked, tanoak-dominated stands. This silviculture is never used in the conifer-dominated stands.
 
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 Shelterwood and Seed Tree: Much of MRC's ownership has been harvested at least once in the last century, some acreage two or three times. In the past, foresters depended largely upon natural regeneration from seed drop verses planting trees to reestablish the conifer stocking following harvest. Towards that goal, a small portion of trees were left behind to produce seed for new stands of trees. This method was intended to be accomplished in steps including re-entry into the stand to remove the residual seed and shelterwood trees. In some cases, regeneration from the seed and shelterwood trees was unsuccessful. MRC is re-entering some of these areas to harvest some of the residual trees and to rehabilitate those acres that did not successfully regenerate with manual planting. Additionally, the younger stands, below the residuals, are often thinned to alleviate overcrowding and maintain healthy growing conditions. In cases of re-entry with Shelterwood or Seed Tree silviculture, trees are always retained across the whole spectrum of sizes and ages including a percentage of the residual trees.
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UNEVEN-AGED MANAGEMENT
Where MRC has well-stocked conifer (redwood and Douglas-fir) forest, MRC maintains that forest in a well stocked condition. Hardwood competition is kept in check naturally with the overstory dominance of the conifers. Any harvest is balanced with growth using various selection silvicultures and harvesting methods. These methods include harvest of single trees or small groups of trees depending on the species, sizes and ages of the trees. Over time, uneven-aged management will develop and maintain a stand of trees with a wide variety of different ages and sizes. Redwood forests grow particularly well using this regime because they can regenerate and grow in some shade.
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 Single Tree Selection: Single Tree Selection silviculture is used primarily to thin conifer-dominated stands of redwood or Douglas fir, or very young stands of redwood and Douglas fir. Redwood (at any age), and young Douglas-fir (up to around 60 years old) will respond well to a stand thinning and "release." As trees are thinned out and the forest canopy is opened around a tree, that tree will begin to increase its annual growth. This increased growth continues until the residual crowns fill back in and the forest canopy closes. Periodic Single Tree Selection harvest (every ten to fifteen years) will maintain steady individual tree growth while allowing for smaller trees to fill in from beneath.
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 Group Selection: In some areas, especially towards the eastern, warmer portions of the MRC property, stands of pure Douglas-fir can be found. Unlike redwood, Douglas-fir cannot successfully regenerate under a heavily shaded canopy. Douglas-fir needs more light to reach maturity. The tree crowns will thin out to a point at which photosynthesis is dramatically reduced. Consequently in pure Douglas-fir stands or areas dominated by Douglas-fir, small group openings are created with Group Selection harvest methods to provide light for growth. If designed correctly, this Group Selection method will maintain a successful stand of uneven-aged trees. MRC also uses Group Selection when clumps of tanoaks are located in a conifer-dominated stand. The tanoak groups are harvested and the areas are then planted to conifer. Typically, Group Selection will involve harvest of groups of trees ranging from about _ acre up to 2 acres. As the group opening increases, there may be small areas of retention left within the openings.
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 Transition: Transition silviculture is a selection system used to develop an un-even aged stand from an even-aged stand with unbalanced or irregular stocking. Transition silviculture involves removal of trees individually or in small groups to create a balance of different stand structure and natural reproduction.
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