Eucalyptus

Scientific name: Eucalyptus grandis  

Class: Dicotyledoneae  

Family: Myrtaceae  

Common name: Rose Gum (Pink eucalyptus)

Distributions 

 In the central area of distribution, Rose Gum grows in alluvial or volcanic marls in valleys and plains at a maximum distance of 160 km from the coast, on the dividing line between Queensland and New South Wales , from latitude 26º to 33º S. The most appropriate soils for cultivation of this tree are the reddish and brown sands of the Northwestern triangle of Corrientes and the coastal strip of Concordia river, the lateritic reddish brown soils (oxisols) of Misiones and northeast of Corrientes, and the brunizems (molisols) of Santa Fe and Buenos Aires coast. When climate and soil conditions are suitable, Eucalyptus grandis has a growth rate higher than any other species. It has the habit of spontaneously losing its branches, giving rise to smooth column-looking stalks.

Characteristics 

Rose gum sapwood is pale pink, and hardwood (duramen) is light to dark reddish. The wood has a straight fiber, is coarse textured and moderately strong. It is moderately durable, but the sapwood is usually resistant to Lyctus borers. Its specific gravity ranges from 0.62 to 0.80. Its density is 0.640 Kg/dm3. This species grows very well, reaching considerable heights at the age of 17.

Wood 

Rose Gum wood is smooth, white, silver green at the base and rough at top levels. It is soft to semi-hard, easy to work with, and accepts nails and clamps. It does not resist decay well when outdoors and cracks easily. Buds are larger and more glaucous. The root has no woody tubercle.

 Uses 

The wood obtained from Eucalyptus grandis is used for construction in general, joinery, triplex, veneer, boatbuilding, floors, wiring poles, forestays and fences. 

Taeda

Scientific name: Pinus taeda L. 

Class: Conifer.  

Family: Pinaceous.  

Common name: Pinotea - Taeda.  

 Distributions 

This tree is native to the south of the United States of America, from the Atlantic coast to Texas . It grows under similar conditions as the Pinus elliotti, but is more resistant to drafts than the latter. It adapts well to wet and temporarily flooded soils, reaching its utmost development in humiferous soils. In our country, it is grown in the coastal region, from Buenos Aires province (including the Delta) to Misiones. It is also becoming an important plantation in the valleys of Cordoba hills and in Tucuman . The geographic origin of the seed is a key factor to forestation success. For example, the seed from the District of Columbia , Florida (USA) features advantages in our coast. It multiplies in greenhouses, but the seed is previously treated to speed up and uniform germination. It requires good humidity control during the first four weeks to avoid damping off. At the age of one year, it is planted with naked roots in winter or in a container in fall and spring.

  Characteristics  

It is a big tree, tall and straight. The crown is pyramidal, with branches looping down. The bark is reddish brown to cinnamon, deeply dented with oblong plates. At the Delta and in Misiones its growth is extraordinary, adding 2-3 cm in diameter and 30 m3/ha per year under normal conditions. The leaves are thin and flexible, 3 per brachiblast, light green in color, even whitish, 15-22 cm long. The buds are ovoid, scaly, reddish brown, rather resinous. The cones are dented, 6-12 cm long, usually 2 to 4, oblong to ovoid, light reddish brown, with thin fruitful scales and mucron fitted with thorn, laterally inserted, sometimes subterminal. They open at irregular intervals and remain attached to the tree for a year after they are ripe. The seeds develop a 4 to 5 mm long rhomboid wing and hard dark brown tegument.

  Wood  

The wood is yellowish white to ochre yellow, with medium gloss, resin-like smell, thin and homogenous texture, straight and clearly veined grain, having a density of 0.460 Kg/dm3. Its contractions are moderate and is quite stable in service. It dries relatively well, and it is advisable to soak or spray it with pentachlorofenate in order to avoid fungi stains. It does not resist decay very well in contact with soil. Easily impregnable in the sapwood and moderately penetrable in the hardwood. It is soft and light, easy to work with and features a good finish when brushed. It accepts nails and screws easily, though application in the early areas of the growth ring may be more difficult as the wood is less hard.

Uses  

The wood is very suitable for cellulose pulp and plywood panels. This is the use generally given to the product resulting from thinning out plantations. Higher diameter rolls, once sawed, are used in construction carpentry, indoor coating, light stages, plywood, containers, barrels, drawers, etc. Its turpentining process is not cost efficient due to the low production of miera.

 Source: The book of trees