Ferrini, F.
1,3, Fini, A.1,
Bussotti, F.1, Tattini, M.2
Presenting author’s e-mail: Francesco.ferrini@unifi.it
1
Department
of Agri-Food Production and Environmental Sciences, section Woody Plants -
University of Florence, Italy
2
Institute for Plant Protection, National Research Council of Italy, Florence,
Italy
3
International Society of Arboriculture - Board of Directors, Champaign, IL
(USA)
The urban environment constrains tree growth
and survival: drought, poor soil quality, soil compaction, light heterogeneity,
transplant shock, pollutants, salinity, pathogens and conflicts with human
activity often cause premature plant death, thus reducing the net benefit by
urban green areas. It is therefore important to better understand the dynamics
leading to tree decline in the urban environment, and to develop strategies and
techniques aimed at improving the horticultural tolerance (i.e. the capacity to
provide benefits, not only to survive, under stressful conditions) of urban
trees. These include nursery pre-conditioning techniques and post-planting
management techniques, but a key role is played by species selection. Hundreds of
species are used in the urban environment, but selection criteria are
frequently based upon aesthetics and whether the species are native or not,
rather than on the tolerance to typical stresses imposed by the built
environment and on the capacity to provide substantial benefits therein. This
has lead to only a limited knowledge about the ecophysiology of shade trees, if
compared to fruit trees and crop species. The ISA supports research in the area
of tree selection for tolerance of urban conditions so that the service life of
trees in our communities is extended and the benefits provided by trees are
maximized.
Therefore, tolerance mechanisms of species
with validated and potential ornamental use and cultural techniques for either
pre-conditioning plants in the nursery or
alleviating stress after planting will be reviewed in the presentation.