General Requirements The Contractor will hand thin trees in designated units. The Contractor will progress at a rate that indicates all required work be accomplished within the performance period. Only trees less than 6” DBH (diameter at breast height) will be cut. Trees 6” DBH and larger will be considered leave trees and should be considered in spacing requirements. It is acceptable to leave tighter spaced clumps of trees if they are 6” DBH or greater. All trees over 2 feet in height should be thinned. Any trees less than 2 feet in height can be left and will not be considered for spacing requirements. All Juniper within the treatment area boundary under 8” DBH shall be cut. Juniper does not occur frequently within the treatment areas. Tree Quality Selection Criteria: The healthiest, dominant trees in the following order of species preference: Lodgepole Pine, Douglas-fir, Ponderosa Pine. Indicators of desirable trees are: straight stems, good crown coloration, good crown form, good crown ratios (> 45%), freedom from insects, diseases, and physical and mechanical damages, vigorous annual growth as indicated by long terminal leader. The indicators of undesirable trees listed in the next paragraph shall determine the trees to be cut; slight defects may be acceptable for leave tree if it is the best selection within a competitive group. Indicators of undesirable trees are: multiple tops, poor crown ratios (< 45%), poor crown form and coloration, crook or sweep in boles, dead or broken tops, large branch diameter, presence of insects, diseases, or physical or mechanical damages, suppression, poor annual growth as indicated by short terminal leader Felling Requirements Cut trees shall be completely severed from the stump. No hang-up "straps" will be permitted. All felled trees shall be severed below the lowest live limb. The maximum stump height shall be 6 inches above ground level, as measured on the uphill side of the tree. Cut trees shall be felled parallel to each other and not crisscrossed or jack strawed. Cut trees shall be felled away from: unit boundaries (into the units), roads, maintained trails, wildlife trails, fence lines, established land corners, and streams. Any trees felled on such areas shall be removed. Old roads that are closed can have cut trees fell across them. This will be on a case-by-case basis. Dead standing trees shall greater than 8 inches DBH shall not be cut. Bearing, section-line, or trail-blazed trees shall not be cut. Unit boundary trees with unit flagging may be cut. Snow damaged, bent over trees will be cut if they are not dead. Slash Clean-up Requirements 1. All thinned/cut trees shall be lopped and scattered. 2. Thinning slash should contact the ground, and slash depths of more than 2 feet (24 inches) will not be acceptable. Slash should be scattered to avoid creating concentrations greater than 2 feet (24 inches) in depth.
