Quebracho is known to be the hardest wood and can withstand 4,570 pounds of force in the Janka hardness test. It is also one of the heaviest woods. Its name comes from the Spanish words "quebrar hacha," meaning axe breaker.
The Janka hardness test is the most commonly used test for testing a wood's strength. The test considers the amount of pressure it takes to embed a steel ball into the wood, up to half of the ball's diameter. Quebracho tested at 23,340 newtons of pressure. The trees are found in South America and are typically light to medium reddish-brown in color. The wood is also known to be very durable and resistant to insect attacks.