We sought to answer the question: How do we restore characteristics of old-growth evergreen mixed-conifer forests in young even-aged stands on upland terrain at Headwaters Forest Reserve (HFR)? We described the old-growth reference condition for three stands at HFR. In each old-growth stand, trees within a 1-ha plot were inventoried. We found coast Douglas-fir ( Pseudotsuga menziesii var. menziesii) and tanoak ( Notholithocarpus densiflorus) well represented while coast redwood ( Sequoia sempervirens) dominated in terms of size. Numbers of understory and overstory trees ha ？1 and average tree sizes were similar among sites, suggesting these were useful goals for restoration. Adjacent to each old-growth stand, we measured recent growth rates of second-growth trees and remnant old trees across a range of tree sizes, stand structures, and densities. The resultant growth models of redwood and Douglas-fir enabled us to project the development of precommercially thinned young stands at HFR forward in time under two silvicultural prescriptions: (i) no further management; and (ii) partial harvesting simulated before trees attained 30 cm dbh. The partial-harvesting prescription reduced stand density and set the young stand on a more rapid trajectory towards the reference condition found at HFR.
References
[1]
Stephenson, N.L. Reference conditions for giant sequoia forest restoration: Structure, process, and precision. Ecol. Appl. 1999, 9, 1253–1265, doi:10.1890/1051-0761(1999)009[1253:RCFGSF]2.0.CO;2.
[2]
Moore, M.M.; Covington, W.W.; Fulé, P.Z. Reference conditions and ecological restoration: A southwestern ponderosa pine perspective. Ecol. Appl. 1999, 9, 1266–1277, doi:10.1890/1051-0761(1999)009[1266:RCAERA]2.0.CO;2.
[3]
White, P.S.; Walker, J.L. Approximating nature’s variation: Selecting and using reference information in restoration ecology. Restor. Ecol. 1997, 5, 338–349, doi:10.1046/j.1526-100X.1997.00547.x.
[4]
Dagley, C.M. Spatial pattern of coast redwood in three alluvial flat old-growth forests in northern California. For. Sci. 2008, 54, 294–302.
[5]
Dagley, C.M.; Berrill, J.-P. Reference Conditions for Old-Growth Redwood Restoration on Alluvial Flats. In Proceedings of Coast Redwood Forests in a Changing California: A Symposium for Scientists and Managers; Pacific Southwest Research Station, Forest Service, US Department of Agriculture: Albany, CA, USA, 2012.
[6]
Van Mantgem, P.J.; Stuart, J.D. Structure and Dynamics of an Upland Old-Growth Forest at Redwood National Park, California. In Proceedings of Coast Redwood Forests in a Changing California: A Symposium for Scientists and Managers; Pacific Southwest Research Station, Forest Service, US Department of Agriculture: Albany, CA, USA, 2012.
[7]
Fritschle, J.A. Identification of old-growth forest reference ecosystems using historic land surveys, Redwood National Park, California. Restor. Ecol. 2012, 20, 679–687, doi:10.1111/j.1526-100X.2011.00832.x.
[8]
Lorimer, C.G.; Porter, D.J.; Madej, M.A.; Stuart, J.D.; Veirs, S.D.; Norman, S.P.; O’Hara, K.L.; Libby, W.J. Presettlement and modern disturbance regimes in coast redwood forests: Implications for the conservation of old-growth stands. For. Ecol. Manag. 2009, 258, 1038–1054, doi:10.1016/j.foreco.2009.07.008.
[9]
Agee, J.K. The landscape ecology of western forest fire regimes. Northwest Sci. 1998, 72, 24–34.
[10]
O’Hara, K.L.; Nesmith, J.C.; Leonard, L.; Porter, D.J. Restoration of old forest features in coast redwood forests using early-stage variable-density thinning. Restor. Ecol. 2010, 18, 125–135, doi:10.1111/j.1526-100X.2010.00655.x.
[11]
Helms, J.A. The Dictionary of Forestry; The Society of American Foresters: Bethesda, MD, USA, 1998; p. 210.
[12]
Reineke, L.H. Perfecting a stand-density index for even-aged forests. J. Agric. Res. 1933, 46, 627–638.
[13]
Shaw, J.D. Application of stand density index to irregularly structured stands. West. J. Appl. For. 2000, 15, 40–42.
[14]
Berrill, J.-P.; Dagley, C.M. Geographic patterns and stand variables influencing growth and vigor of Populus tremuloides in the Sierra Nevada (USA). ISRN For. 2012, 2012, doi:10.5402/2012/271549.
[15]
US Department of the Interior Bureau of Land Management and California Department of Fish and Wildlife. Headwaters Forest Reserve Proposed Resource Management Plan and Final EIS/EIR; Environmental Impact Statement: Arcata, CA, USA, 2003.
[16]
Long, J.N.; Daniel, T.W. Assessment of growing stock in uneven-aged stands. West. J. Appl. For. 1990, 5, 93–96.
[17]
Berrill, J.-P.; Jeffress, J.L.; Engle, J.M. Coast Redwood Live Crown and Sapwood Dynamics. In Proceedings of Coast Redwood Forests in a Changing California: A Symposium for Scientists and Managers; Pacific Southwest Research Station, Forest Service, US Department of Agriculture: Albany, CA, USA, 2012.
[18]
Eng, H. Tree Height Estimation in Redwood/Douglas-fir Stands in Mendocino County. In Proceedings of Coast Redwood Forests in a Changing California: A Symposium for Scientists and Managers; Pacific Southwest Research Station, Forest Service, US Department of Agriculture: Albany, CA, USA, 2012.
[19]
Hermann, R.K.; Lavender, D.P. Douglas-Fir. In Silvics of North America: 1 Conifers; Burns, R.M., Honkala, B.H., Eds.; US Department of Agriculture, Forest Service: Albany, CA, USA, 1990.
[20]
Spies, T.A.; Franklin, J.F. The Structure of Natural Young, Mature, and Old-Growth Douglas-Fir Forests Oregon and Washington. In Wildlife and Vegetation of Unmanaged Douglas-Fir Forests; Pacific Southwest Research Station, Forest Service, US Department of Agriculture: Albany, CA, USA, 1991; pp. 91–109.
[21]
Berrill, J.-P.; O’Hara, K.L. Patterns of leaf area and growing space efficiency in young even-aged and multiaged coast redwood stands. Can. J. For. Res. 2007, 37, 617–626, doi:10.1139/X06-271.
