232
8.5.2 Aspidosperma Quebracho-Blanco (Apocynaceae)
This is an evergreen sclerophyllous tree species, 6–20 m in height and up to 1 m in
diameter. Its trunk is straight; the bark is grayish brown with deep longitudinal
grooves (Demaio et al. 2002). The species has two biological forms: an erect form
with an ovoid crown and a pendulum form with a crown of decumbent branches
(Giménez and Moglia 2003a, b). The fruit is a woody, ovoidal rounded or elongated
capsule, 7–11 cm long by 4–6 cm wide and 1–2 cm thick, grayish green. Seeds are
suborbicular, with a diameter between 5 and 7 cm including a membranous wing
(Orfila 1995), which facilities their dispersion by the wind. Its wood is hard and
heavy (0.85 kg/dm
3
), white-yellowish to ocher yellow, with soft grain and no difference between sapwood and heartwood. The wood is predominantly used for the
elaboration of traditional products (charcoal, firewood, and sleepers but also sawn
wood); it has problems in some applications due to instability and a certain tendency to suffer contractions, swellings, and warping (Giménez and Moglia 2003a,
b). It is extremely slow growing, finding trees in the forests that are 40 cm in diameter and over 200-year old (Chaca and Saravia 2014).
Aspidosperma quebracho-blanco is the Chaco forest tree species with the widest
geographical distribution (Fig. 8.8), due to which it has aroused interest as a carbon
sink (Gaillard de Benitez et al. 2002; Barrionuevo et al. 2013). It even ranges to the
Espinal and the Monte (Barchuk and Valiente-Banuet 2006) and is also distributed
in the southeast of Bolivia, western Paraguay, and western Uruguay. In Argentina, it
can be found in some sectors of Mesopotamia with annual rainfall of more than
1100 mm and in the Monte with less than 300 mm per year. It also occupies an
enormous diversity of soils. It is not an “azonal” species but a “climax” one, since
Fig. 8.8 Schematic Argentine range of Aspidosperma quebracho-blanco (Oyarzabal et al. 2018)
A. Verga and D. López Lauenstein
8.5.2 Aspidosperma Quebracho-Blanco (Apocynaceae)
This is an evergreen sclerophyllous tree species, 6–20 m in height and up to 1 m in
diameter. Its trunk is straight; the bark is grayish brown with deep longitudinal
grooves (Demaio et al. 2002). The species has two biological forms: an erect form
with an ovoid crown and a pendulum form with a crown of decumbent branches
(Giménez and Moglia 2003a, b). The fruit is a woody, ovoidal rounded or elongated
capsule, 7–11 cm long by 4–6 cm wide and 1–2 cm thick, grayish green. Seeds are
suborbicular, with a diameter between 5 and 7 cm including a membranous wing
(Orfila 1995), which facilities their dispersion by the wind. Its wood is hard and
heavy (0.85 kg/dm
3
), white-yellowish to ocher yellow, with soft grain and no difference between sapwood and heartwood. The wood is predominantly used for the
elaboration of traditional products (charcoal, firewood, and sleepers but also sawn
wood); it has problems in some applications due to instability and a certain tendency to suffer contractions, swellings, and warping (Giménez and Moglia 2003a,
b). It is extremely slow growing, finding trees in the forests that are 40 cm in diameter and over 200-year old (Chaca and Saravia 2014).
Aspidosperma quebracho-blanco is the Chaco forest tree species with the widest
geographical distribution (Fig. 8.8), due to which it has aroused interest as a carbon
sink (Gaillard de Benitez et al. 2002; Barrionuevo et al. 2013). It even ranges to the
Espinal and the Monte (Barchuk and Valiente-Banuet 2006) and is also distributed
in the southeast of Bolivia, western Paraguay, and western Uruguay. In Argentina, it
can be found in some sectors of Mesopotamia with annual rainfall of more than
1100 mm and in the Monte with less than 300 mm per year. It also occupies an
enormous diversity of soils. It is not an “azonal” species but a “climax” one, since
Fig. 8.8 Schematic Argentine range of Aspidosperma quebracho-blanco (Oyarzabal et al. 2018)
A. Verga and D. López Lauenstein