Graduation Date
Spring 2019
Document Type
Thesis
Program
Master of Science degree with a major in Natural Resources, option Forestry, Watershed, & Wildland Sciences
Committee Chair Name
Dr. John-Pascal Berrill
Committee Chair Affiliation
HSU Faculty or Staff
Second Committee Member Name
Dr. Kevin Boston
Second Committee Member Affiliation
HSU Faculty or Staff
Third Committee Member Name
Dr. Harold Zald
Third Committee Member Affiliation
HSU Faculty or Staff
Keywords
Silviculture, Stump sprouts, Coppice, Variable retention, Tree growth, Thinning response, Uneven-aged silviculture, Sequoia sempervirens
Subject Categories
Forestry
Abstract
There is increased interest in multiaged management as a silvicultural and restoration tool in redwood forests of California. The effect of varying residual densities and spatial arrangements on residual stand damage, tree growth and regeneration was studied in a multicohort silviculture experiment on Jackson Demonstration State Forest. Four treatments varying in residual stand density or spatial arrangement were replicated at four sites. The experiment provided 4-year periodic growth measurements of residual trees and annual measurements of redwood and tanoak sprout height increments. Residual trees were more likely to sustain bole scarring when retained at higher densities. Crown damage was more likely to be sustained by smaller trees. From 2-6 years after partial harvesting, redwood trees grew faster than Douglas-fir or tanoak following harvest. The height increment of dominant redwood stump sprouts was much greater than dominant tanoak sprouts across all treatments and the growth of both species was directly correlated to understory light. No differences were detected for any dependent variables between dispersed and aggregated retention. No differences in sprout growth were detected when retaining a residual tree on the same root system as sprouting redwood stumps when compared against sprouts growing on a root system after all redwood stems were cut. Overall, these results suggest that managers have flexibility to manage multiaged redwood stands at different densities, and that retention of low densities of large trees will provide a good balance between overstory tree growth and understory development in multiaged stands while reducing incidences of residual stand damage.
Citation Style
APA
Recommended Citation
Muma, Robert Thomas, "Converting coast redwood/Douglas-fir forests to multiaged management: residual stand damage, tree growth, and regeneration" (2019). Cal Poly Humboldt theses and projects. 269.
https://digitalcommons.humboldt.edu/etd/269