Common Name(s): Quebracho, Quebracho Colorado, Red Quebracho
Scientific Name: Schinopsis spp. (S. balansae, S. brasiliensis, S. lorentzii, S. quebracho-colorado)
Distribution: Tropical South America
Tree Size: 30-50 ft (9-15 m) tall, 1-3 ft (.3-1 m) trunk diameter
Average Dried Weight: 77 lbs/ft3 (1,235 kg/m3)
Specific Gravity (Basic, 12% MC): 1.03, 1.24
Janka Hardness: 4,570 lbf (23,340 N)
Modulus of Rupture: 20,540lbf/in2 (141.7 MPa)
Elastic Modulus: 2,407,000 lbf/in2 (16.60 GPa)
Crushing Strength: 12,080 lbf/in2 (83.3 MPa)
Shrinkage: Radial: 4.3%, Tangential: 8.2%, Volumetric: 13.1%, T/R Ratio: 1.9
Color/Appearance: Heartwood color typically a light to medium reddish brown, sometimes with darker blackish streaks. Color darkens upon prolonged exposure to light. Pale yellow sapwood distinct from heartwood, though transition is gradual.
Grain/Texture: Quebracho has a fine, uniform texture with a high natural luster. Grain tends to be irregular, roey, and interlocked.
Endgrain: Diffuse-porous; small to medium pores in no specific arrangement; primarily in radial multiples of 2-3; fairly high pore density (many pores per square inch); tyloses and other heartwood deposits present; growth rings usually indistinct; rays not visible without lens; parenchyma vasicentric.
Rot Resistance: Quebracho is rated as very durable, and is also resistant to insect attacks. Quebracho also has excellent weathering characteristics.
Workability: Difficult to work on account of its density and irregular grain. High cutting resistance, as well as pronounced blunting effect on cutters. Dries slowly—and tends to crack, check, and warp while drying. Turns and finishes well, and also able to take on a high natural polish without any finishing agents.
Odor: There is no characteristic odor associated with this wood species, though it is reported to have a bitter taste.
Allergies/Toxicity: Although severe reactions are quite uncommon, Quebracho has been reported to cause respiratory irritation, as well as nausea. See the articles Wood Allergies and Toxicity and Wood Dust Safety for more information.
Pricing/Availability: Very seldom available in the United States, Quebracho is somewhat elusive as an imported hardwood. Expect prices to be in the medium to high range for an exotic wood.
Sustainability: Quebracho is not listed in the CITES Appendices, and the IUCN reports that Schinopsis quebracho-colorado and S. balansae are species of least concern, though S. haenkeana is on the Red List as vulnerable due to a population reduction of over 20% in the past three generations, caused by a decline in its natural range, and exploitation.
Common Uses: Heavy construction, railroad cross-ties, and fence posts (within its natural range), as well as furniture, and turned objects (when exported).
Comments: The name Quebracho is from the Spanish quebrar hacha, which literally means “axe breaker.” Aptly named, wood in the Schinopsis genus is among the heaviest and hardest in the world.
Quebracho was heavily exploited in the late 1800s for use in leather tanning. The tanin-rich heartwood (up to 20-30%) is cut into small chips, where the tanins can subsequently be extracted.