General Features

 Deciduous tree, endemic from the subantarctic forests of Chile and Argentina.

 It presents two botanical varieties in Chile, the macrocarpa variety represents the more septentrional distribution of the genus in south america (33° SL), and the obliqua variety has the greatest distribution, between 33°57’ to 41°10’ SL.

 It has natural hybridization with Nothofagus glauca (Phil.) Krasser "Hualo" generating Nothofagus leonii Espinosa "Huala", which has intermediate features from its parental species and it is endemic to the chilean central zone.

 If prefers deep and fertile soils, also it gets well adapted to other kind of soils where the humidity is not restricted.

 In its north distribution it grows in streams borders with alluvial soils at an altitude between 1,000 and 2,000 m, where roble tends to grow dwarf and with a barely commercial value.

 In this situations it grows in pure stands as the only dominant specie, with a shrub-like underbrush.  In the high forests it tends to grow in pure form, but in some areas, the more humid conditions, it can grow with peumo, boldo, quillay or lingue.

 In the south area and close to streams, it can grow in mixture with rauli, coihue, lingue, canelo, mañio de hojas largas, avellano y laurel.  In high lands it gets mixed with rauli, constituting the Forest Type Roble-Rauli.

 In low lands and hillsides roble grows together with lingue and laurel in park-like formations.  In the south areas, roble grows together with evergreen species that are distinctive from the valdivian forest.
 

Botanical Characteristics

 Roble is a deciduous monoic tree, of 20 m, but it can reach 40 m of height and between 40 cm to 2 m in diameter, it has a cylindrical stem and a hard and thick bark, fissured in big plaques.

 It presents a pyramidal crown, very branched.

 It has subcoriaceous or coriaceous leaves, from aovate to aovate-lanceolate form, they are alternate, notoriously asymmetric in the base with irregularly serrate-tooth borders, with a very variable size that depends from the provenance, they are 2 to 5 cm long and 1.5 to 3 cm wide, they can be glabrous or pubescent, with resinous papillas in his adaxial face, and pale green in the back.

 The flowers are unisexual, small, that develop in the extremes of the new branches.

 The masculine flowers are solitaire, shortly petiolate, surrounded by a pubescent involucre that contains 30 to 40 stamens.

 The feminine flowers have between 2 to 3 stigmas, they can be found by three, protected by a cupule or pubescent involucre, that it is cover with appendixes in the back, the involucre has a size of 8x6 mm, with 4 valves and it is dehiscent.

 The fruits are nuts with a oval to pyramidal form, they are woody from 4 to 8 mm long and 6 mm wide, they are grouped by three in the cupule’s interior, the central one is bi-winded and the lateral ones are tri-winded, they are protected by the cupule with 4 wide and oval valves.

 The number of seeds per kg, varieties from 50,000 to 150,000, the viability oscillates depending on the production year from 11 to 43%, with a high proportion of vane seeds, this process it can be explained by biannual cycles.

 The seeds are microbiotics and they can be keep alive for no longer than two years in natural conditions.  The conservation in dry storage at 2°C, with a humidity content under 10%, it allows to keep them close to 20 years.  The germination is epigeal.

Phenology

 The flowering occurs at the beginning of spring, between September and October and the fruits maturation occurs between February and April.
 

Importance

 Roble is one of the species of greater distribution and abundance in Chile and it can live in very different habitats in his natural distribution.

 Its wood presents good resistance and durability characteristics, it is employed in bridge construction, posts, veneers, exterior wood, etc.  It presents a high economic interest in the mill industry.

 Its sapwood is whitish to yellowish not very resistant to the inclemency, its heartwood is reddish, and is called "pellin".  The adult trees with the reddish wood are the most valuable ones because of this red, hard, heavy, inclemency resistance wood.

 Some experimental plantations developed in Chile reach at 20 years old a height between 16 to 18 m and a growth of 15 to 17 m3/ha/year.

Prepared by:  Maria Teresa Serra V.  Departamento de Silvicultura, Facultad de Cs. Agrarias y Forestales.  Universidad de Chile.
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