FACTORS INFLUENCING STREET TREE HAZARD CONDITION IN RAFAELA, ARGENTINA

CASTRO, DAMIÁN C.; ALESSO, C. AGUSTÍN; IACONIS, ARIANA; CERINO, MA. CAROLINA; BUYATTI, MARCELA

REVISTA ÝRVORE

UNIV FEDERAL VICOSA

Año: 2019

0100-6762

Understanding the factors that aff ect tree hazard condition is important to mitigate it. To quantify these factors for Fraxinus americana L., Morus nigra L., and Populus deltoides Marshall trees we have conducted a surveyrecording their hazard rating according to the TRAQ methodology. The following covariates were registered for each tree: the number of single tree defects in root collar, trunk and scaff old branches, trunk diameter at breast height DBH),crown class, crown asymmetry, and the size of the tree pit. A multi-category logistic regression model was fi tted to the data using the backward step-wise procedure. Among the factors considered, only the species, crown class, number of single defects in root collar and scaff old branches signifi cantly aff ected the tree hazard condition. P. deltoids trees had higher values of hazard compared to F. Americana and M. nigra trees. Trees with co-dominant crowns presented a higher probability of being classifi ed as medium and high hazardous than trees with suppressed and dominant crowns. Finally, every single defect observed on root collar and scaff old branches increased the probability of a tree being of medium or high hazardous, by about 3.00 and 1.44 times, respectively. Other factors like crown asymmetry, DBH, and the tree pit size did not have a signifi cant eff ect on the score of tree hazard. Our results demonstrate that the species selection is an important tool to manage urban tree hazard under the study conditions. At the species level, eff orts should be directed towards minimizing defects in root collar, trunk and scaff old ranches.