Fungi associated to Platanus x acerifolia in Uruguay and failure indicators

Abstract

In the last few years, the interest in keeping the city trees healthy has increased in order to improve their survival and minimize claims due to potential accidents. The pest and diseases, the pollution, and the climate change together with the little genetic diversity of trees in urban areas are some of the factors that contribute to increase the likelihood of death and/or failure of trees in the cities. This work is part of a sanitary and risk of failure assessment of plane street trees (Platanus x acerifolia) carried out between 2019 and 2020. A random sample of 10 city blocks and their 193 plane trees was selected. In these, the presence of cankers, abnormal bark colorations, deformations, and a series of structural attributes that determine likelihood of failure variables were registered. The proportion of individuals with each symptom and the severity main index (SMI) were calculated as a weighted average of the different severity (SEV) levels in the total of evaluated plants. The severity indices were determined according to trunk or branches circumference and the portion of the tree affected (1st, 2nd or 3rd portion from the base). Deformations presented the main incidence (0.6), SMI (1.68) and a correlation with the presence of damages and human injuries. The presence of cankers and reddish bark were the symptoms that most affected the density of the crowns.