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2. REALIZATION
After planning, the following step is the realization of the forestry intervention, which will be
successful as much the planning has been accurate. In addition to more “operational” steps, such as
bedding out of plants, it is important to examine also the first maintenance activities, fundamental in
order that every plant roots well and survives for long time. Generally, the minimum period to be sure
of the achievement of forestry intervention is about 3 years
51, also if some maintenance interventions
could last more.
Following are analyzed the main steps for the realization of a model forestry intervention
(independent from the function that the new area will must have):
1.
Preparatory activities: all the activities necessary to analyze and to prepare the soil will be
examined (such as rock removal, weed removal, etc.);
2.
Implantation: all aspects connected to bedding out of trees/shrubs will be examined (such as
the time and way of planting, planting pattern, digging, etc.);
3.
First maintenance: interventions necessary after the bedding out of plants will be analyzed
(irrigation, soil surface processing, etc.).
2.1 Preparatory activities
All the activities necessary to correctly prepare the soil are essential for the achievement of the
forestry interventions, because they create suitable conditions for the further steps. Preliminary
activities vary in relation to the site characteristics: a disused area will request major interventions
(such as reclamation) respect to, for example, an untamed area. In this phase, then, it is extremely
important to consider all the previous analysis realized during planning, with particular reference to
soil and botanical characteristics (cf. 1.2).
Following, all the main procedures to realize before the bedding out of plants are analyzed. Not all
of them are always required: for example in sites located inside a protected area it is probable that rock
and weed removal will be not necessary.
2.1.1 Rock removal
This procedure is indispensable in degraded areas (such as disused areas, abandoned sites in urban
areas, etc.), while in natural/seminatural areas it is better to avoid it if the rockiness is of natural origin.
It is an intervention to be considered yet during planning, because equipment, time and ways can
request quite high economic resources.
In every case, all waste and building residues must be removed in the site.
2.1.2 Weed removal
Vegetal pest species frequently settle in abandoned areas, and they should be removed before
planting new trees and shrubs. Among pest species, for example, tree of heaven (
Ailanthus altissima
)
and black cherry (
Prunus serotina
) have to be removed, because very invasive. However, this kind of
procedure should be realized only if pest species can represent a threat for the existing natural
vegetation. Otherwise, for example along streets, these exotic species, being pioneer species, can
contribute to the creation of ecological corridors.
Furthermore, sometimes, like in natural areas, it is not necessary to remove all vegetation, but, on
contrary, it is opportune to leave existing vegetation, for aesthetic/landscape reasons, for biodiversity
maintenance and/or for creating suitable conditions for the planting (for example if the site is sloping it
is better not to remove the vegetation, which contribute to the stability of the area).
For this procedure it is possible to use different equipment (brush cutter, tractors, etc.), depending
on site characteristics (extension, existing vegetation, accessibility, etc.).
2.1.3 Soil processing
The best soils for trees are those with an adequate nutrient supply, well aerated and, in addition,
suitable for root “exploration”. For these reasons it is necessary to process soil before the planting of
51
Lassini et al., 1998.
Forestazione urbana per la Lombardia
. Regione Lombardia e Azienda Regionale delle Foreste.