sdu faculty of forestry journal special edition 2009 - Orman Fakültesi

SDU Faculty of Forestry Journal
Serial: A, Number: Special Issue, Year: 2009, ISSN: 1302-7085, Page: 219-232
URBAN TREE HEALTH OF 49 GREEN SPACES IN MADRID (SPAIN)
Eva ALFONSO CORZO 1 *, M.J. GARCIA-GARCIA 1 , J.A. SAIZ de OMEÑACA 1
ABSTRACT
1 Technical University of Madrid, Madrid, Spain
* alfonso_corzo@hotmail.com
In order to improve the management of the urban tree health in Madrid, a sample of 49
green spaces was evaluated. Data were obtained by visual assessment in 6 different districts
of the city, during a period of 3 or 4 years. Diseases, pests and other problems were
identified for each species in every green area, without considering the number of trees.
The health status of the trees declined along the period and there were few differences
among the districts. The main problems in trees were stem injury, dead branches, epicormic
shoots and decay, and the most damaged species were Siberian elm (Ulmus pumila), Black
locust (Robinia pseudoacacia), Box elder (Acer negundo), and Plane tree (Platanus
hispanica). Decay was related with stem injury. Biotic diseases were encountered less
frequently than abiotic, and they affected a smaller rank of species. The results showed a
positive association between naturalness of species and their health status, with a higher
damage risk among the exotic ones. Based on their health features, a ranking of the less
suitable species to be grown in Madrid is given.
Keywords: urban green space, tree health, shrub, naturalness, abiotic disease
1. INTRODUCTION
The city constitutes a hostile environment for ornamental vegetation because
many adverse conditions may affect the plants living in it: from environmental
factors such as urban heat island, air pollution or mechanical stem injury to biotic
stresses such as pests and diseases. Several authors have reported different
difficulties which are related with the urban environment (Impens and Delcarte,
1979; Rocray, 1983; Berrang et al., 1985). These factors not only injure the plants,
but, some of them also predispose plants to suffer from another diseases
(Kozlowski, 1985), interacting synergistically.
In order to improve vegetation management of the green spaces in Madrid, the
city council commissioned a survey to the Forestry Pathology Department of the
Technical University of Madrid, which was carried out from 2005 to 2008.
The study has four principal objectives in trees, shrubs, vines and seasonal
flowers populations:
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