Dr Valerie M LeMay

Professor, Forest Biometrics and Forest Measurements

My areas of research are focused on:

  • Spatial analyses models and methods to provide information up to larger spatial scales or down to local scales
  • Imputation methods (nearest neighbour, model-based, etc.) for integrating multivariate and multi-source forest inventory information at one time and over time
  • Developing methods to link growth and yield models with forest inventory data for forest level analyses
  • Estimation of regeneration following partial cutting using overstory and ecological information using model-based and distribution-free methods
  • Developing measures of structural diversity, including indices that combine spatial, species, and size heterogeneity
  • Spatial analyses of tree spatial patterns over time using parameter prediction within a mixed-effects modelling framework
  • Tree taper, volume, crown length, and leaf area models using nonlinear mixed-effects models
  • Estimating tree internal decay using tobit, distribution-free, and other estimators
  • Modelling changes in tree taper and shape over time
  • Spatio-temporal analyses of plants and animals
  • Meta-analysis of field experimental data for impacts of spacing and other silvicultural prescriptions
  • Meta-analysis of published information for genetic impacts on growth at the stand-level

Teaching:

I teach courses in forest biometrics and forest measurements including:  introductory and advanced forest measurements;  information and data for forest management and conservation; advanced modelling using mixed-effects linear, nonlinear, and generalized linear models; applied multivariate analyses; and experimental design and analysis using a model-based approach. I have developed workshops on most of these topics, including one-day workshops on tree and stand measurements to obtain a estimate of volume, biomass, and carbon per ha for a small area.


Awards

Faculty of Forestry Killam Teaching Award , 2004
Nominated for Graduate Students Mentoring Award , 2004
Faculty of Graduate Studies Killam Teaching Award , 2011

Current Courses

Winter 2019

FRST239 Tree and Stand Level Measurements Sections

An introduction to measurement of individual trees and stands; use of aerial photographs, maps, and various measurement instruments.

Winter 2019

FRST530 Multiple Regression Methods Sections

Matrix algebra; algebra and inference of multiple linear and multiple curvilinear regressions for solution of problems in forestry and related fields. Non-linear regression. Methods of least squares for analysis of variance and covariance.

Winter 2019

FRST533C Problems in Statistical Methods - PROBS STAT METHD Sections

Directed studies in problems of advanced statistical techniques as a tool in forest research.

Winter 2019

FRST556 Land Information Acquisition and Analysis Sections

Principles and application of data acquisition and use.

 


Other Courses and Workshops

Selected Publications


Lochhead, Kyle, Valerie Lemay, Gary Bull, Olaf Schwab, and James Halperin (2018). Multivariate estimation for accurate and logically-consistent forest-attributes maps at macroscales Canadian Journal of Forest Research 48(4): 345-359/ www.nrdresearchpress.com/cjfr
Bravo, F., R. Jandl, and V. LeMay, (Eds.) (2017). Managing Forest Ecosystems: the challenge of climate change. 2nd edition Springer
De Montigny, L., S. Ahmed & V. LeMay (2016). The effects of planting density on the growth and yield of lodgepole pine, interior spruce, interior Douglas-fir, and western larch: 16-26 year result from EP 964. Tech. Rep. TR098, 50 pp. / Province of BC, Victoria, BC.
Halperin, J. and V. LeMay. (2016). A review of multiple frame survey estimators for use in forest inventory. Ministry of Forests, Lands, and Natural Resources Operations, Victoria, BC.
Ferster, C.J., B.N.I. Eskelson, D.W. Andison, and V.M. LeMay (2016). Vegetation mortality within natural wildfire events in the western Canadian boreal forest: what burns and why? MDPI Forests 7(9):187
J. Halperin, V. LeMay, E. Chidumayo, L. Verchot, and P. Marshall (2016). Model-based estimation of above-ground biomass in the miombo ecoregion of Zambia Forest Ecosystems, Springer 3:14, 14 pp.
Halperin, J. V. LeMay, N. Coops, L.Verchot, P. Marshall, K. Lochhead (2016). Canopy cover estimation in miombo woodlands of Zambia: Comparison of Landsat 8 OLI versus RapidEye imagery using parametric, nonparametric, or semiparametric methods Remote Sensing of Environment pp. 170-182 DOI 10.1016/j.rse.2016.03.028
Power, H. F. Berninger, V.M., LeMay, and D. Kneeshaw (2015). Pipe-model ratio distributions and branch foliage biomass: Differences between two sympatric spruce species Scandinavian Journal of Forest Research
Wall, J., G. Wittemyer, V. M. Lemay, I. Douglas-Hamilton, and B. Klinkenberg (2014). Elliptical time-density model to estimate wildlife utilization distributions Methods in Ecology and Evolution
Baker, K., G. Bull, and V. LeMay (2014). The use of fuelwood market segmentation and product differentiation to assess opportunities and value: A Nicaraguan case study Energy for Sustainable Development
Wall, J., G. Wittemyer, B. Klinkenburg, V. LeMay, and I. Douglas-Hamilton (2013). Characterizing properties and drivers of long distance movements by elephants (Loxodonta africana) in the Gourma, Mali Elsevier Biological Conservation 157:60-68.
Ahmed, S. and V. M. LeMay (2013). Meta-Regression to Scale Tree Mortality Models to a Regional Scale ForValueNet Research Note
Power, H., V. LeMay, F. Berninger, D. Sattler, and D. Kneeshaw (2013). Crown lengths and profiles of black (Picea mariana) and white (Picea glauca) spruce NSERC ForValueNet ForValueNet Research Note
Beiler, K.J., Simard, S.W., Lemay, V., and Durall, D.M. (2012). Vertical partitioning between sister species of Rhizopogon fungi on mesic and xeric sites in an interior Douglas-fir forest Molecular Ecology, 21: 6163-6174.
Power, H., V. LeMay, F. Berninger, D. Sattler, and D. Kneeshaw (2012). Differences in crown characteristics between black (Picea mariana) and white spruce (Picea glauca) Canadian Journal of Forest Research (formerly was NRC Press) Canadian Journal of Forest Research 42:1733-1743
Sattler, D. and V. LeMay (2011). A system of nonlinear simultaneous equations for crown length and crown radius for the forest dynamics model SORTIE-ND NRC Press Canadian Journal of Forest Research 41:1567-1576.
Rathbun, L.C., V. LeMay, and N. Smith (2011). Diameter growth under varying silvicultural treatments for mixed-species stands of coastal British Columbia using a random coefficients modelling approach Elsevier Ecological Modelling 222(14):2234-2248.
Pommerening, A., V. LeMay, and D. Stoyan. (2011). Model-based analyses of the ecological factors determining point pattern formation in forests. Elsevier Ecol. Model 222(3): 666-678.
McLane, S.C., V.M. LeMay, and S.N. Aitken (2011). Modeling lodgepole pine (Pinus contorta) radial growth relative to climate and genetics using universal growth-trend response functions. Ecological Society of America Ecological Applications 21: 776-788.
Wang, Y, V.M. LeMay, and T.G. Baker (2011). Modeling growth responses of individual trees to early-age thinning in Eucalyptus globulus, E. Nitens and E. Grandis plantations in northern Victoria. Institute of Foresters of Australia Australian Forestry Journal 74(1):62-72.
Barbeito, I, V. LeMay, R. Calama, and I. Canellas (2011). Regeneration of Mediterranean Scots pine (Pinus sylvestris) under alternative shelterwood systems within a multiscale framework. NRC Press Canadian Journal of Forest Research 41: 341-351.
Rathbun, L., V. LeMay and N. Smith. (2010). Modelling mortality for mixed-species stands located in coastal British Columbia NRC Press Canadian Journal of Forest Research 40:1517-1528.
LeMay, V. and A. Pommerening. (2010). Nearest neighbour imputation for edge correction of sample plots. Invited talk presented at the XIII IUFRO World Congress, Seoul, Korea, August 23 to 28, 2010.
Klady, R.A., G.H.R. Henry, and V. LeMay (2010). Changes in high arctic tundra plant reproduction in response to long-term experimental warming Wiley-Blackwell Global Change Biology 17:1611-1624.
Sattler, D., V.M. LeMay, and P.L. Marshall (2009). Estimating natural regeneration using a linked-model approach. Presented at the Crown Models and Simulation Methods Conference. Aug. 7 to 10, 2007, Portland, OR. USDA For. Serv. Gen. Tech. Rep. PNW-GTR-791. pp. 69-77.
Eskelson, B.N.I., H.Temesgen, T.M. Barrett, V. LeMay, N.L. Crookston, and A.T. Hudak (2009). The roles of nearest neighbor methods in imputing missing data in forest inventory and monitoring databases Taylor & Francis Scandinavian Journal of Forest Research 24(3): 235-246.
LeMay, V., A. Pommerening, and P. Marshall (2009). Spatial-Temporal Structure of Multi-Storied, Uneven-Aged Interior Douglas-fir (Pseudotsuga menziesii var. glauca (Mirb.) Franco) Stands Wiley-Blackwell Journal of Ecology 97(5):1062-1074
Bater, C.W., Coops, N.C., Gergel, S.E., LeMay, V.M. and Collins, D. (2009). Estimation of standing dead tree class distributions in northwest coastal forests using lidar remote sensing NRC Press Canadian Journal of Forest Research 38: 6, 1080-1091.
LeMay, V., A. Pommerening, and P. Marshall. (2009). Examining variation in stand structure and spatial arrangements over time. Presentation made at IUFRO Div. 4 Meeting: Extending Forest Inventory and Monitoring over Space and Time. Quebec City, PQ. May 20-22, 2009. Summary Paper published at: http://blue.for.msu.edu/meeting/proc2/LeMay_Pommerening_Marshall.pdf
Sattler, D., V. LeMay, and P. Marshall (2008). A hybrid modelling approach to estimating establishment and growth of advanced regeneration BC Journal of Ecosystems and Management 9(3): 93-97.
LeMay, V., J. Maedel, and N. C Coops. (2008). Estimating stand structural details using variable-space nearest neighbour analyses to link ground data, forest cover maps, and landsat imagery. Elsevier Remote Sensing of Environment. 118: 2578-2591
Bravo, F., V. LeMay, R. Janld, and K. von Gadow (Eds.) (2008). Managing Forest Ecosystems: the challenge of climate change Springer Book Publishers Springer Book Publishers
LeMay, V. and W.A Kurz (2008). Estimating carbon stocks and stock changes in forests: linking models and data across scales Springer Book Publishers In: Managing forest ecosystems: the challenge of climate change. Edited by: F. Bravo, V. LeMay, R. Jandl, and K. vonGadow.
Sattler, D. F., V. LeMay, and P. Marshall (2008). Estimating natural regeneration in stands following attack by mountain pine beetle using a linked-model approach. USDA Forest Service Proceedings of the IUFRO Crown models and simulation methods conference, Portland, OR, August 6 to 10, 2007. USDA For. Serv. Gen. Tech. Rep.
Mahon, C.L, K. Martin, and V. LeMay (2008). Do cross-scale correlations confound analysis of nest site selection for chestnut-backed chicadees? Cooper Ornithological Society The Condor 110: 563-568
LeMay, V., and C. Staudhammer (2007). A stand structural diversity index for horizontal, vertical and spatial diversity. Paper presented at the IUFRO Complex Stands Structures and Associated Dynamics: measurement indices and modelling approaches, Sault Ste. Marie, Ontario, Canada, July 29 to August 2, 2007 Canada Forest Service Popular summaries of papers presented at the IUFRO Complex Stands Structures and Associated Dynamics: measurement indices and modelling approaches, Sault Ste. Marie, Ontario, Canada, July 29 to August 2, 2007
A-A. Zumrawi , V. LeMay and P. Marshall (2007). PrognosisBC : An Adaptation of a Single Tree Model to Southeastern British Columbia. Popular Summary. Canada Forest Service Presented at Complex Stand Structures and Associated Dynamics: Measurement Indices and Modelling Approaches. July 29 to Aug. 2, 2007, Sault Ste. Marie, Ontario. Ontario Forest Research Institute, Forest Research Information Paper 167. pp. 81-82.
LeMay, V., T. Lee, D. Sattler, P. Marshall, D. Robinson, and A-A. Zumrawi (2007). Modeling natural regeneration following mountain pine beetle attacks in the southern and central interior of British Columbia Canadian Forest Service, Pacific Forestry Centre, Victoria, B.C. Mountain Pine Beetle Initiative Working Paper 2007-16.
LeMay, H. Temesgen, A-A. Zumrawi, and P.L. Marshall (2007). Ingrowth and mortality in partially cut complex stands of South-Eastern BC and Extensions to MPB-affected stands of Central BC Presented at the “Complex Stands Research and Management Conference”, Smithers, BC, February 19-20, 2007 [Abstract in Proceedings only]
Moss, I, P. Marshall, and V. LeMay (2007). Assessment of the status of forest inventories in British Columbia: A summary report Association of British Columbia Forestry Professionals http:/www.abdfp.ca/publications_forest/publications/committee_reports.asp
LeMay, V., T. Lee, D. Sattler, P. Marshall, D. Robinson, A-A. Zumrawi (2007). Modeling Natural Regeneration Following Mountain Pine Beetle Attacks in the Southern and Central Interior of British Columbia. -Mountain Pine Beetle Initiative Working Paper 2007–16. 51 pp.
Lee, T., P. Marshall, V. LeMay, and A-A. Zumrawi (2006). Estimating natural regeneration following Mountain Pine Beetle attacks in British Columbia using nearest neighbour analyses Proceedings of the IUFRO Nearest Neighbors Workshop: Meeting in the Middle, University of Minnosota, Minneapolis, MN, August 28 to 20, 2006. [Extended Abstract in Proceedings]
LeMay, V., T. Lee, R. Scott, D. Sattler, D. Robinson, A.-A. Zumrawi, and P. Marshall (2006). Modeling natural regeneration following mountain pine beetle attacks in the Southern and Central Interior of British Columbia. Results for Year 1. -Natural Resources Canada, MPB Standard Contribution Agreement PO #8.25. 96 pp.
Salas, C., V.LeMay, P. Nunez, P. Pacheco, A. Espinosa (2006). Spatial patterns in an old-growth Nothofagus oblique forest in South-Central Chile Elsevier For. Ecol. & Manage. 231:38-46
LeMay, V. and W. Kurz (2006). Estimating carbon stocks and stock changes in forests: linking models and data across scales. IUFRO Div. 4 and Universidad de Valladolid Proceedings of the IUFRO Div. 4 2006 International Meeting: Managing Forest Ecosystems: The Challenges of Climate Change, April 3rd-7th, 2006. [Abstract on page 6; full paper on associated CD]
Wang, Y., V.LeMay, and T. Baker (2006). Nonlinear mixed effects modelling for improving site-specific prediction of dominant height growth of Eucalyptus globulus plantations. Proceedings of the XXIII International Biometric Conference in Montreal, Canada, July 16-21, 2006.
Bowering, M., V.M. LeMay, and P.L. Marshall (2006). Effects of forest raods on the growth of adjacent lodgepole pine (Pinus contorta Dougl. var. latifolia Englem.) trees. NRC Press Canadian Journal of Forest Research 36:919-929
Akindele, S.O. and V.M. LeMay (2006). Development of tree volume equations for common timber species in tropical rain forest areas of Nigeria Elsevier Forest Ecol. & Manage. 226:41-48.
LeMay, V. and N. Smith (2005). Measurement and analysis issues for complex stands of British Columbia Abstract in Proceedings of the XXII IUFRO WORLD CONGRESS in Brisbance, Australia, August 8 to 14, 2005.
Schultz, R., P. Marshall, and V. LeMay (2005). Predicting time-since-fire using forest inventory data: A case study in the boreal forest of Saskatchewan, Canada. Abstract in Proceedings of the XXII IUFRO WORLD CONGRESS, Brisbane, Australia, August 8 to 14, 2005
Suratman, N.M., V.M, LeMay, G.Q. Bull, D.G. Leckie, N. Walsworth and P.L. Marshall. (2005). Logistic regression modeling of thematic mapper data for rubber (Hevea brasiliensis) area mapping Science Letters 2(1):79-84.
Staudhammer, C., V.M. LeMay, R.A. Kozak and T.C. Maness (2005). Mixed-Model Development for Real-Time Statistical Control Data in Wood Products Manufacturing. Forest Biometry, Modelling and Information Sciences 1(2005):19-35.
Hassani, B., A.-A. Zumrawi, V. LeMay, and P. Marshall. (2005). Implementing a PrognosisBC regeneration sub-model for complex stands of southeastern and central British Columbia: Use in MPB-affected stands and results of long-term projections in partially cut stands. -Report submitted to BC Forest Science Program, Project No: Y051355. 31 pp.
LeMay, V.M. and C. Staudhammer (2005). Indices of stand structural diversity: adding spatial diversity to a stand structural index. Extended Abstract. Proceedings of the IUFRO Sustainable Forestry in Theory and Practice: Recent Advances in Inventory & Monitoring, Statistics, Information & Knowledge Management, and Policy Science Conference, Edinburgh, Scotland, April 5 to 8, 2005. 4 pp.
Zumrawi, A-A., V. LeMay, and P.L. Marshall (2005). PrognosisBC: Model and current research. -Presented at Growth and Yield Models for Central and NE BC, Prince George, BC, June 29, 2005. (web site for presentations)
Marshall, P.L. and V.M. LeMay (2005). Forest inventory pp. 577-604 in S.B. Watts and L. Tolland (eds.), Forestry Handbook for British Columbia. Fifth Edition. University of British Columbia Forestry Undergraduate Society, Vancouver, BC.
LeMay, V. and H. Temesgen (2005). Comparison of nearest neighbour methods for estimating basal area and stems per ha using aerial auxilliary variables. Society of American Foresters Forest Science 51(2): 109-119.
LeMay, V. and H. Temesgen (2005). Connecting inventory information sources for landscape level analyses. -Forest biometry, modelling, and information sciences (FBMIS) 1:37-49
Temesgen, H., V. LeMay, and S. Mitchell (2005). Tree crown ratio models for multi-species and multi-layered stands. Forestry Chronicle 81:133-141
LeMay, V. (2004). Brief overview of forestry and information issues in Canada. Presented at the University of Stellenbosch, Stellenbosch, South Africa, November 4, 2004
LeMay, V. and A. Robinson. (2004). Inventory: Design, performance, and analysis of experiments. Elsevier Academic Press, San Diego Encyclopedia of Forest Sciences. J. Burley, J. Evans, and J.Z. Youngquist, eds. Vol. 1, pp. 158-163
Hassani, B., V. LeMay, P.Marshall, H.Temesgen, and A.A. Zumrawi. (2004). Regeneration imputation models for complex stands of southeastern British Columbia Canadian Institute of Forestry Forestry Chronicle 80(2): 271-278.
Suratman, M.N., G.Q. Bull, D.G. Leckie, V. LeMay, and P.L. Marshall (2004). Modeling stand volume of rubber (Havea brasiliensis) plantations in Malaysia using Landsat TM. Science Letters 1:65-71.
Suratman, M.N., G.Q. Bull, D.G. Leckie, V. LeMay, P.L. Marshall, and M.R. Mispan (2004). Prediction models for estimating volume, age, and area of rubber (Havea brasiliensis) plantations in Malaysia using Landsat TM data. Commonwealth Forestry Association International Forestry Review 6(1):1-13
Suratman, M.N., G.Q. Bull, D.G. Leckie, V. LeMay, and P.L. Marshall. (2004). Development and application of a rubber (Hevea brasiliensis) stand volume model in Selangor, Malaysia, using Landsat TM data. -In. Lee S.S., H. Aminah, H. Norini, S. Lim, H. Lim. Conference on Forestry and Forest Products Research., Kuala Lampur, Malaysia. October 6-8, 2003, 139-149p.
LeMay, V., and P. Marshall. (2004). Issues and methods for experimental design for complex stands in Canada. [Invited presentation] -Presented at Design and Evaluation in Uneven-Aged Forests and Mixed Stands, Zermatt, Switzerland, March 20-27, 2004.
LeMay, V.M., P.L. Marshall, and A. Zingg. (2004). Measurement and analysis issues for complex stands. [Invited presentation] -Presented at the 2nd International Conference of Forest Measurements and Quantitative Methods and Management & the 2004 Southern Mensurationists Meeting, Hot Springs, Arkansas, USA. June 15-18, 2004
Suratman, N.M, G. Bull, D. Leckie, V. LeMay, and P. Marshall (2004). Linking between policies and land use/cover change as detected by Landsat TM in Malyasia Abstract in Proceedings of the XXII IUFRO WORLD CONGRESS, Brisbane, Australia, August 8 to 14, 2005
Temesgen, H., V. LeMay, and I. Cameron (2003). Bivariate distribution functions for predicting twig leaf area within hybrid spruce crowns. NRC Press Can. J. For. Res. 33:2044-2051
Temesgen, H., V.M. LeMay, K.L. Froese, and P.L. Marshall. (2003). Imputing tree-lists from aerial attributes for complex stands of southeastern British Columbia. Elsevier Forest Ecology and Management 177:277-285.
LeMay, V.M. and P.L. Marshall. (2003). Forward. Canadian Journal of Forest Research Special Edition on the “Forest Modelling for Ecosystem Management, Forest Certification, and Sustainable Management Conference. NRC Press Can. J. For. Res. 33(3): vii.
Staudhammer, C., and V.M. LeMay (2001). Introduction and evaluation of possible indices of stand structural diversity NRC Press Can. J. For. Res. 31: 1105-1115.
Staudhammer, C. and V.M. Lemay. (2000). Height prediction equations using diameter and stand density measures. Canadian Institute of Forestry Forestry Chronicle 76(2):303-309.
Wang, Y., S.J. Titus, and V.M. LeMay (1998). Development of slenderness coefficient predictive models for major species of boreal mixedwood forests in Alberta. 22 pp. plus Tables and Figures. NRC Press Can. J. For. Res. 28:1171
Muhairwe, C., V.M. LeMay, and A. Kozak (1996). Sensitivity of a variable exponent taper function to changes in crown class, age, site, crown ratio, and average stand diameter. NRC Press Can. J. For. Res. 24: 252-259
Wang, Y., V.M. LeMay, and P.L. Marshall (1996). Relative efficiency and reliability of parametric and non-parametric sequential accuracy testing plans. NRC Press Can. J. For. Res. 26:1724-1730.
LeMay, V.M., D. Tait, and B. VanderKamp (1994). Classification of cedar, aspen, and fir trees as decayed versus sound. NRC Press Can. J. For. Res. 24: 2068-2077.
LeMay, V.M. (1993). Percent decay estimation using decayed wood area at breast and stump height NRC Press Can. J. For. Res. 23:307-312
Chai, F. and V.M. LeMay (1993). Development and testing of diameter increment models for Mixed Swamp Forests of Sarawak Elsevier J. For. Ecol. & Manage. 58:51-64
LeMay, V.M., A. Kozak, and P.L. Marshall (1993). Using limited dependent variable estimators for estimating percent decay NRC Press Can. J. For. Res. 23:266-274.
Newton, P.F. and V.M.LeMay (1992). Evaluation of a sequential counting plan for point-density estimation within black spruce/balsam fir seedling populations -Elsevier For. Ecol. & Manage. 53:195-212
LeMay, V.M. (1990). MSLS: A technique for fitting a simultaneous system of equations with a generalized error structure. NRC Press Can. J. For. Res. 20:1830-1839