International Society of Arboriculture P.O. Box 3129 Champaign, IL 61826-3129 NONPROFIT ORG U.S. POSTAGE PAID Champaign, IL PERMIT No. 328 ARBORICULTURE ARBORICULTU CONTENTS Gregory A. Dahle, Kenneth R. James, Brian Kane, Jason C. Grabosky, and Andreas Detter A Review of Factors That Affect the Static Load-Bearing Capacity of Urban Trees ............................................................................................................ 89 Jason J. Griffin, William R. Jacobi, E. Gregory McPherson, Clifford S. Sadof, James R. McKenna, Mark L. Gleason, Nicole Ward Gauthier, Daniel A. Potter, David R. Smitley, Gerard C. Adams, Ann Brooks Gould, Christian R. Cash, James A. Walla, Mark C. Starrett, Gary Chastagner, Jeff L. Sibley, Vera A. Krischik, and Adam F. Newby Ten-Year Performance of the United States National Elm Trial .............................. 107 Alvaro Sánchez-Medina, Esperanza Ayuga-Téllez, Lucrecia Contato-Carol, M. Ángeles Grande-Ortiz, and Concepción González-García Selection of Tree-Size Variables for Appraisal Methods for Urban Trees According to Their Collinearity ..............................................................................................121 Conversion Chart (Metric to Imperial) ..................................................................132 & www.isa-arbor.com ISSN: 1935-5297 URBAN FORESTRY Volume 43, Issue 3, May 2017 Formerly the Journal of Arboriculture, 1975 – 2005 (Volumes 1 – 31)