Silviculture and Cinegetics Review - Societatea Progresul Silvic

FORESTRY BELTS SILVICULTURE AND CINEGETICS REVIEW XVII/30/2012
demanding to the edaphic conditions, it grows well on
dry, shallow soils with high content of calcium
carbonate; it shows resistance to drought and frost. It
needs intensive summer heat. Growth is active in youth,
at 5 years achieving heights of 2-3 m, but weakens with
age. It has tap-spreading roots, with long lateral
branches, deeply rooted, that are deeper and richer than
the cherry’s. It sprouts and suckers weakly. Its use is
recommended mainly in the case of shallow, coarse
soils, with high content of calcium carbonate, in the
marginal and post marginal rows of the field and road
protection belts.
White mulberry (Morus alba) was used in the railway
protection belts (Brăila and Galalţi counties), intimately
mixed with shrubs and tree species; it has a medium
open temperament. Being resistant to drought and
winter frosts, it sometimes suffers because of the early
frosts. It shows modest to edaphic conditions, growing
even on compressed soils, having good results
especially on cambic, argillic chernozems and alluvial
soils. Mulberry resists rather well to insects and very
well on fungi attacks. Growth is slow in the first year,
then very active, at age 5 years achieving height of 2-3
m, and its longevity is of approx. 150 years. It has tapspreading
roots; it sprouts weakly. It reacts well to
pruning, so it can be used to form hedges. It may be
used in the steppe and forest steppe, in the central part
of the field and communication protection belts.
Osage-orange (Maclura aurantiaca), although this is
an exotic species, was frequently used in the railway
belts installed during 1950-1960, mainly in the marginal
and post marginal rows, having a mid-shade
temperament. Resistant to drought, it develops well on
fertile soils, but it also led to good results on alluvial
soils (Photo 9). It sprouts abundantly and it suckers
well. It shows a dense crown, with rich foliage, which is
particularly important to its use in the snow protection
forest belts. Growth is quite rapid. It has deep, richly
branched roots, being an option for the border of
communication protection belts.
Oleaster (Elaegnus angustifolia) was used mainly in
the field and anti-erosion belts, in the marginal rows,
having an open temperament. It has a large ecological
amplitude and grows quite actively even on salty soils,
but the best on more humid soils. It shows a great
resistance to frost, but prefers a climate with warm
summers.
Its particular rusticity confers its quality of species
recommended to hard situations of installation of forest
vegetation, with poor soils (alluvial protosols and salty,
but not too dry soils).
Under favorable vegetative conditions, growth is very
active (it reaches 2-3 m height three years after
plantation - Vulturu-Vrancea experimental block). It has
spreading roots; it sprouts and suckers.
Research has shown that its introduction in black locust
based field protection forest belts, in the outer rows, on
chernozem soils, had poor results. Due to its strong
open temperament and active growth, on the northern
side of the forest belts, searching for light, oleaster
developed asymmetrically (baggy), towards the exterior
of the forest belt.
Under the aforementioned conditions, in winters with
abundant precipitation, snow crown accumulation has
produced serious sharp bending and breakage of trunk
and branches.
On the other hand, its thin and flabby crown ensures a
weak contribution to density regulation (i.e. to create a
reduced penetration in the road protection belts), and
hinders the development of tree species in the
immediate vicinity. Better results were obtained by
using osage-orange or honey locust in similar site
conditions.
With all the disadvantages mentioned, oleaster is
recommended for use in all types of protection forest
belts, in hard to extreme site conditions, on poor and
even salty soils, on marginal and post marginal rows,
mixed with shrubs (Photo10).
Common walnut (Juglans regia) was analyzed based
on research on some alignments installed along the
roads (Mărăşeşti, Focşani) and on field protection forest
belts (Bărăganu Station) or roadside (Suraia).
Planted on chernozem soils and deep coluvisoils,
strongly humiferous, walnut shows a good vegetative
state, growth being active. It has tap, strongly developed
roots and sprouts quite vigorously.
However it was noted that where planting distance
between trees was less than 5-6 m, their crowns show an
asymmetric development, branches do not overlap but
derange each other and fructification is weak.
Furthermore, the sanitary cuts made in the crown have
not led to expected effects, emphasizing their
asymmetry. Instead, trees located at 8-10 m have a
much better crown and trunk conformation, and a good
fructification, due to walnut pronounced open
temperament.
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