Answer: quebracho

AnswerCrossword Clue
quebrachoany of several tropical American trees of the genus Schinopsis, having very hard wood, esp. S. lorentzii, the wood and bark of which are important in tanning and dyeing
quebracho(Spanish) any of several tropical American trees and their timber or bark
quebrachothe wood or bark of any of these trees
quebrachotree, Aspidosperma quebrachoblanco, of the dogbane family, yielding a medicinal bark