title: Nondestructive detection of decay in living trees.
abstract: We used a four-point resistivity method to detect wood decay in living trees. A low-frequency alternating current was applied to the stem and the induced voltage measured between two points along the stem. The effective resistivity of the stem was estimated based on stem cross-sectional area. A comparison within a group of trees showed that trees with butt rot had an effective resistivity that was at least a factor of two lower than that of healthy trees. In tests on several groups of Norway spruce (Picea abies (L.) Karst.) comprising more than 300 trees in total, the method detected butt rot with high accuracy. We validated the method both by measurements and by finite element modeling and simulations.
authors.affiliation: Department of Electroscience, Lund Institute of Technology, Box 118, 211 00 Lund, Sweden.
authors.forename: Bertil
authors.initials: B
authors.lastname: Larsson
authors.forename: Bengt
authors.initials: B
authors.lastname: Bengtsson
authors.forename: Mats
authors.initials: M
authors.lastname: Gustafsson
mesh_terms: D017097:Electric Impedance; D028222:Picea / Q000382:microbiology / Q000502:physiology; D010935:Plant Diseases / Q000382:microbiology; D018547:Plant Stems / Q000382:microbiology / Q000502:physiology; D014197:Trees / Q000382:microbiology / Q000502:physiology