Herb Pharm prepares their Pau d Arco Extract from the dried inner bark of purple-flowered Tabebuia impetiginosa trees, which is Sustainably Wildcrafted in its native habitat. To assure optimal extraction of Pau d Arcos bioactive compounds, Herb Pharm only uses the inner bark which is hand-harvested, carefully sun-dried and cleaned of adhering wood, and is then thoroughly extracted.