Silviculture and Cinegetics Review - Societatea Progresul Silvic

FORESTRY BELTS SILVICULTURE AND CINEGETICS REVIEW XVII/30/2012
The most effective and sustainable intimately mixed
cultures are the ones that optimize space requirements
and resources by avoiding competition between the
two parts - trees and crops. It is necessary to consider
the challenges involved in intimately mixed cultures:
identification of installation difficulties and finding
better ways to set up these agroforestry systems, using
the most suitable compositions, namely the use of
those agricultural species that are less competitive for
forest cultures species than are weeds, knowledge of
dynamics of plants in crop intimately mixed etc.
Stationary conditions (soil and climate) may be
limiting factors in achieving the intimate mixture of
cultures. For example, in areas with depleted soil is
not practiced this system, primarily because
agricultural species contribute to a more pronounced
depletion of the soil, then because forest species will
be installed with difficulty in terms of competition
with agricultural species.
Forest species preferred for association with the
agricultural ones this agroforestry system are usually
the fast growing ones such as: hybrid poplars, black
locust, Paulownia, but you can use also moderate
growing species such as ash, walnut or even slow
paced growing (oak species).
Agricultural species used in this agroforestry system
are: corn, sunflower, soybean, and medicinal herbs
(lavender, mint, fennel etc.), species of vegetables etc.
3.2. Intercropping
Intercropping is another type of agroforestry
system in which crops shall be installed and develop
between the bands (strips) of trees and / or shrubs
(composed of one or two lines), situated at distances
determined by the main production goals of the
system (Fig. 3). The distance between the bands varies
therefore depending on the objectives and priorities
established within the agroforestry system, being
equal to the multiple of the width of machines used in
maintenance and harvesting of crops (over 12 m
distance). Distance between trees on the row ranges,
at planting, from 0.75 m, if they have as their primary
function protection against soil erosion, and 2 m, if it
seeks production of wood or fruit.
Fig. 3. Intercropping euramerican poplar - wheat.
Experiment conducted in the European project SAFE
(Sylvoarable Agroforestry for Europe). Vezenobres,
France (Eichhorn et al., 2006)
The purpose of achieving this system is to increase
production of the main compound, which is the
agricultural one, to diversify the overall production of
the system (both long and short term) and to improve
its quality.
The presence of trees in agricultural crops contributes
to soil stabilization, by stopping erosion and reducing
landslides helping soil water infiltration. Trees crowns
protect crops against winds and reduce the effect of
heavy rains. Moreover, the presence of trees aims to
improve the circulation of nutrients, enhance
diversity, and beautify landscape.
Under this agroforestry system crops coexist with
trees simultaneously, the first providing annual
production, while the trees grow, develop and mature
in a longer period of time. Thus, it is diversified
production on the same land area and therefore
income, which can come both from crops and from
forestry. The presence of trees in the intercropping
system may prevent any loss of production due to
climatic excesses (heavy rain, strong winds etc.).
Forest species used in intercropping are fruit trees,
poplar, oak, ash, cherry, chestnut, pine, paulownia,
walnut. To achieve a stable sustainable agroforestry
system forest species must meet certain conditions, as
follows: i) to be adapted to environmental and soil
conditions where they are to be planted; ii) to be in
relationships of low competitiveness with agricultural
species; iii) to provide one or more high quality
products (wood, bark, resin, leaves, flowers, fruit,
tannins, etc..), and these products to be sold; iv) to be
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