Guidelines suistainable urban forestry ROMA_Eng

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are the gardens of agricultural biodiversity where variety of fruit trees belonging to rare or
endangered local cultivars are reproduced and preserved;
• to favour species with dense foliage and branching, which may represent suitable habitat for
nesting. Also the presence of the cavity, especially at the base of the trunk, is a factor which
can promote the fauna, which can use them as a shelter;
• to avoid toxic species for wildlife, such as oleander (Nerium oleander);
• to increase biodiversity, another intervention than can be designed alongside the forestation is
the creation of wetlands, which further diversifying the environment, provides other suitable
habitats for the fauna (amphibians, waterfowl, etc.), especially in large areas.
Some species that can be used to increase the animal biodiversity are:
• hackberry (Celtis australis), as well as having a large canopy, produces small edible fruits,
sweet taste, trophic resource for many birds;
• laurel (Laurus nobilis), evergreen species that can be found both as tree and shrub. In addition
to being used as a refuge by the fauna, this species can be used to mitigate noise and air
pollution;
• various species of the family Rosaceae, including fruit shrubs and trees, are suitable to provide
food resources (flowers and fruits) and shelter to wildlife. Among the species are cited, for
example, the wild apple (Malus sylvestris ), cherry (Prunus avium) and the canine cherry (P.
mahaleb , not native in Rome), the common rowan (Sorbus domestica) and among the shrubs,
hawthorn (Crataegus monogyna), blackthorn (Prunus spinosa) and cherry laurel (Prunus
laurocerasus, not native in Rome). Species of other families with similar quality is black elder
(Sambucus nigra ). A problem to evaluate about use of these species is that they are subject to
be infected by fire blight (caused by Erwinia amylovora). It is therefore appropriate that the
Rosaceae are used in association with other species not susceptible to such an infection, in
order to avoid the risk of failure of the forestry intervention;
• wild olive (Olea europeae), spontaneous form of the olive, long-lived species and rustic
withstands, heat-loving and light-loving;
• the poplars (in Rome are indigenous Popus alba , P. nigra and P. canescens) are home to a rich
insect fauna (Häne & Kaennel Dobbertin, 2006) ;
• the Fabaceae shrubs (Spartium junceum , Cytisus spp., Emerus major) and woody labiates
(Teucrium fruticans) are favourable to the food supply for Apoidea and other Artropoda.
Finally, recently, in addition to the use of fruit species, is spreading also the use of aromatic species
(lavender, thyme, red pepper, etc., Figure 4), especially to form ornamental or delimitation hedges
(e.g. urban green areas, areas of dogs, etc.). These species, although not arboreal, round up the
environment and therefore may contribute to the increase of local biodiversity.
In order to encourage biodiversity is desirable to plan the realization of real urban ecological
networks using, for example, the redevelopment of the banks of river waters and the mitigation of the
infrastructural network.
40 For example see Emilia Romagna experiences in
41 Häne, K., Kaennel Dobbertin M., 2006. Le peuplier noir : un géant aux pieds d'argile. La Forêt, 7/8.