Faculty and Staff

Pascal Berrill – Associate Professor, Silviculture & Restoration

Personal and Research Interest

My teaching and interdisciplinary research focus on silviculture and restoration. Often this involves filling knowledge gaps to support wise management of forests by understanding the underlying ecology, physiology, and the linkages between these disciplines i.e., how can we use/expand our understanding of physiological processes and linkages between the growth of a forest and its environment to better manage forest ecosystems. Key areas of research interest include: degraded/threatened forest restoration, multiaged silviculture, tree response to stress/climate change, carbon forestry (silviculture to maximize biomass production/carbon sequestration), and how variations in the natural environment affect results from these research areas.

My professional background is in applied forest management and commercial silvicultural research, growth and yield modeling, and intensive plantation management – establishment, pruning, and thinning practices to maximize value. Academic research background includes monitoring restoration of degraded forests, multiaged management of mixed conifer forests, leaf area index and growth efficiency modeling, geostatistics and spatial pattern analysis, multivariate analysis methods, and linkages between forest ecology, productivity, regeneration, and stand structure.

I serve on the California State Board of Forestry’s Research & Science Committee, a group of scientists representing the diversity of institutions, disciplines and geographic locales in the state.

Education and Degrees
Courses Taught
Selected Publications

Hammett, E.J.; Ritchie, M.W.; Berrill, J-P. 2017. Resilience of California black oak experiencing frequent fire: regeneration following two large wildfires 12 years apart. Fire Ecology 13(1): 91-103.

Berrill, J-P.; Han, H-S. 2017. Carbon, harvest yields, and residues from restoration in a mixed forest on California’s Coast Range. Forest Science 63(1): 128-136.

Zeibig-Kichas, N.E.; Ardis, C.W.; Berrill, J-P.; King, J.P. 2016. Bark thickness equations for mixed-conifer forest type in Klamath and Sierra Nevada Mountains of California. International Journal of Forestry Research, Vol. 2016, ID: 1864039, 1-10.

Kirk, C.; Berrill, J-P. 2016. Second-Log Branching in Multiaged Redwood and Douglas-Fir: Influence of Stand, Site, and Silviculture. Forests 7(147): 1-15.

Berrill, J-P.; O’Hara, K.L. 2016. How do biophysical factors contribute to height and basal area development in a mixed multiaged coast redwood stand? Forestry 89: 170–181.

Perry, D.W.; Breshears, L.W.; Gradillas, G.E.; Berrill, J-P. 2016. Thinning Intensity and Ease-of-Access Increase Probability of Bear Damage in a Young Coast Redwood Forest. Journal of Biodiversity Management and Forestry 5(3):1-7.

Berrill, J-P.; Dagley, C.M.; Coppeto, S.A. 2016. Predicting Treatment Longevity after Successive Conifer Removals in Sierra Nevada Aspen Restoration. Ecological Restoration 34(3): 236-244.

Namm, B.N.; Berrill, J-P. 2016. Tanoak (Notholithocarpus densiflorus) Coarse Root Morphology: Prediction Models for Volume and Biomass of Individual Roots. Open Journal of Forestry 6: 1-13. doi: 10.4236/ojf.2016.61001

Berrill, J-P.; O’Hara, K.L. 2015. Spatial Variation in Dominant Height and Basal Area Development in a Coast Redwood Forest: Implications for Inventory and Modeling. Biodiversity Management and Forestry 4(4): 1-6. doi:10.4172/2327-4417.1000147

Crotteau, J.S.; Ritchie, M.W.; Varner, J.M.; Berrill, J-P. 2015. Quercus kelloggii (Newb.) Sprout Response to Fire Severity in Northern California. Pp. 377-386 In: Standiford, R.B.; Purcell, K.L., tech. cords. Proceedings of the seventh California oak symposium: managing oak woodlands in a dynamic world. Gen. Tech. Rep. PSW-GTR-251. Berkeley, CA: U.S. Department of Agriculture, Forest Service, Pacific Southwest Research Station. 579 p.

Berrill, J-P.; Dagley, C.M. 2014. Regeneration and recruitment correlate with stand density and composition in long-unburned aspen stands undergoing succession to conifer in the Sierra Nevada, USA. Forest Research: Open Access.

Berrill, J-P.; O’Hara, K.L. 2014. Estimating site productivity in irregular stand structures by indexing basal area or volume increment of the dominant species. Canadian Journal of Forest Research 44(1): 92-100.

Berrill, J-P.; Beal, C.B.; LaFever, D.H.; Dagley, C.M. 2013. Modeling young stand development towards the old-growth reference condition in evergreen mixed-conifer stands at Headwaters Forest Reserve, California. Forests 4(2): 455-470.

Dagley, C.M.; Berrill, J-P.; Coppeto, S.; Jacobson, K. 2012. Effects of slash pile burning after restoring conifer-encroached aspen: interim pile building guidelines for aspen injury risk reduction. USDA Forest Service, Lake Tahoe Basin Management Unit Monitoring Report, December 2012.

Berrill, J-P.; Dagley, C.M. 2012. Geographic patterns and stand variables influencing growth and vigor of Populus tremuloides in the Sierra Nevada (USA). ISRN Forestry Vol. 2012, ID: 271549, 9 pages. doi:10.5402/2012/271549.

Berrill, J-P.; Jeffress, J.L.; Engle, J.M. 2012. Coast redwood live crown and sapwood dynamics. Pp. 473-484 in Standiford, R.B.; Weller, T.J.; Piirto, D.D.; Stuart, J.D. (tech. coords.). Proc. of Coast redwood forests in a changing California: a symposium for scientists and managers. USDA Forest Service Gen. Tech. Rep. PSW-GTR-238. Albany, CA. 675 p.

Namm, B.H.; Berrill, J-P. 2012. Accounting for variation in root wood density and percent carbon increases accuracy of belowground carbon estimates. Pp. 293-302 in Standiford, R.B.; Weller, T.J.; Piirto, D.D.; Stuart, J.D. (tech. coords.). Proc. of Coast redwood forests in a changing California: a symposium for scientists and managers. USDA Forest Service Gen. Tech. Rep. PSW-GTR-238. Albany, CA. 675 p.

Berrill, J-P.; O’Hara, K.L. 2012. Influence of tree spatial pattern and sample plot type and size on inventory estimates for leaf area index, stocking, and tree size parameters. Pp. 485-497 in Standiford, R.B.; Weller, T.J.; Piirto, D.D.; Stuart, J.D. (tech. coords.). Proc. of Coast redwood forests in a changing California: a symposium for scientists and managers. USDA Forest Service Gen. Tech. Rep. PSW-GTR-238. Albany, CA. 675 p.

Dagley, C.M.; Berrill, J-P. 2012. Stand structure in old-growth redwood alluvial flat forests of northern California. Pp. 251-263 in Standiford, R.B.; Weller, T.J.; Piirto, D.D.; Stuart, J.D. (tech. coords.). Proc. of Coast redwood forests in a changing California: a symposium for scientists and managers. USDA Forest Service Gen. Tech. Rep. PSW-GTR-238. Albany, CA. 675 p.

Berrill, J-P.; Dagley, C.M. 2012. Vegetative response to weed control in forest restoration. Pp. 363-380 in Hasaneen, M. (Ed.). Herbicides - Properties, Synthesis and Control of Weeds. InTech Open Access: 492 p.

Berrill, J-P. 2011. An even-aged approach to forest regeneration and biodiversity. California Forests 15(1): 14-15.

Berrill, J-P.; Dagley, C.M. 2010. Assessing longleaf pine (Pinus palustris) restoration after southern pine beetle kill using a compact experimental design. Scandinavian Journal of Forest Research 25(8): 75-85.

Valness, C.M.; Berrill, J-P.; Libby, W.J. 2010. Effects of differential brush competition on giant sequoia and mixed conifer associates in a common garden trial. Ecological Society of America Annual Conference, Pittsburg, PA. August 2010. (Poster presentation).

Dagley, C.M.; Berrill, J-P. 2010. A monitoring strategy for riparian forest restoration. 5th Biennial Lake Tahoe Basin Science Conference; Measuring Success of Ecosystem Restoration in Lake Tahoe Basin. Incline Village, NV. March 2010. (Poster presentation).

Berrill, J-P. ; Dagley, C.M. 2010. Preliminary stocking guidelines for aspen restoration in the LTBMU: Comparing thinning prescription diameter limits. Report prepared for Lake Tahoe Basin aspen forest managers.

O'Hara, K.L.; Berrill, J-P. 2010. Dynamics of coast redwood sprout clump development in variable light environments. Journal of Forest Research 15(2): 131-139.

O'Hara, K.L.; Berrill, J-P. 2009. Epicormic sprout development in pruned coast redwood: Pruning severity, genotype, and sprouting characteristics. Annals of Forest Science 66(409): 1-9.

Berrill, J-P.; O'Hara, K.L. 2009. Simulating multiaged coast redwood stand development: Interactions between regeneration, structure, and productivity. Western Journal of Applied Forestry 24(1): 24-32.

Berrill, J-P.; O'Hara, K.L. 2007. Patterns of leaf area and growth efficiency in young even-aged and multiaged coast redwood stands. Canadian Journal of Forest Research 37(3): 617-626.

Berrill, J-P.; O'Hara, K.L. 2007. Modeling coast redwood variable retention management regimes. P. 261-269 in Standiford, R.B.; Giusti, G.A.; Valachovic, Y.; Zielinski, W.J., Furniss, M.J., (Eds.) of the Redwood Region Forest Science Symposium: What does the future hold? March 15-17, 2004, Rohnert Park, California. USDA Forest Service Gen. Tech. Rep. PSW-GTR-194. Albany, CA. 553p.

Berrill, J-P.; O'Hara, K.L. 2007. Redwood silviculture in California: An overview of silvicultural systems. New Zealand Tree Grower 28(1): 11-13.

Berrill, J-P.; Nicholas, I.D.; Gifford, H.H. 2007. A preliminary growth model for New Zealand grown Acacia melanoxylon. New Zealand Journal of Forestry Science 37(1): 37-56.

Berrill, J-P.; Hay, A.E. 2006. Indicative growth and yield models for stringybark eucalypt plantations in northern New Zealand. New Zealand Journal of Forestry 51(1): 19-22.

Berrill, J-P.; Hay, A.E. 2005. Indicative growth and yield models for even-aged Eucalyptus fastigata plantations in New Zealand. New Zealand Journal of Forestry Science 35(2/3): 121-138.

Berrill, J-P. 2004. Preliminary growth and yield models for even-aged Cupressus lusitanica and C. macrocarpa plantations in New Zealand. New Zealand Journal of Forestry Science 34(3): 272-292.

Pascal Berrill
Contact Information:

Office: 109 Natural Resources Building
Email: pberrill@humboldt.edu
Ph. 707.826.4220
Fax: 707.826.5634

Mailing Address:

Department of Forestry and Wildland Resources
1 Harpst Street