Pau d’arco bark, often called Taheebo or Lapacho, comes from the Pink Ipê or Pink Lapacho tree (Tabebuia impetiginosa, syn. T. avellanedae) which grows in Central and South America1, everywhere from northern Argentina to northern Mexico2. The Lapacho tree can grow up to 30 meters and, when in bloom, it is completely covered with pink flowers which make it visible from a distance of several miles5,1. Unsurprisingly, it has become the national tree of Paraguay2. In its native county the tree is known as Pau d'arco. The most probable origin of this local name is the term palo d'arco which means ‘wood for a bow’3. Several Indian tribes used to make their hunting bows form Pau d’arco wood. The Tupi and Guarani Indians used the name ‘tajy’ for the tree, a verb which means ‘to have strength and verve4.
There are about 100 other trees and shrubs in the genus Tabebuia, apart from Lapacho. Many of them have similar medicinal properties. However, Lapacho, that is Labebuia impetiginosa, is the most popular and most tested tree with proven health benefits. The bark taken from this tree is sometimes referred to as Red Lapacho to distinguish it from the raw material obtained from other Tabebuia species.
It is the dried inner bark of the Lapacho (Tabebuiae cortex)5, and sometimes the wood itself, which is used for medical products. The outer bark is not used as it has fewer active substances.
The majority of commercially available pau d’arco products contain bark which has been obtained from the wood in a lumber mill. At least 10 different species of Tabebuia are felled in the forests. However, as the lumber mills receive only the bare tree trunks, with no leaves or flowers which would enable identification of a particular Lapacho species, they all get sold under the one name of pau d’arco. This explains why different pau d’arco products may contain active substances differing in action or in amounts.
Some suppliers supplemented Lapacho bark with the bark of the Jackfruit tree (Artocarpus heterophyllus) or the Brazilian Pepper tree (Schinus terebinthifolius)6. Occasionally even mahogany chips, which have a similar smell and color, have been swept from the floor of the lumber yard and sold as pau d’arco4. This shows the importance of choosing a credible, verified supplier when making your purchase.