Information pertaining to the Patagonian Walnut wood species is detailed below:

Specie Names
Botanical Name: Tabebuia, heptaphylla.
Lumber Name(s): Lapacho.
Grown in: Paraguay, Southern Brazil.
Description
Patagonian Walnut is in the same family as Brazilian Walnut/Ipe. It has a lighter brown color than Brazilian Walnut and offers golden/tan highlights. It also offers more rowed grain/curl figure than Brazilian Walnut.

Color Range and Color Change
Color Range: Patagonian Walnut ranges in color from a golden tan to a medium-brown color. Some pieces may have some darker brown graining.
Color Change: Patagonian Walnut exhibits a medium degree of color change; the wider color range in the freshly milled wood will quickly mute to become more uniform. The overall hue will also darken from a fresh milled gold/greenish color to a medium brown tone with golden highlights.

Where to Use
Patagonian Walnut may be used residentially or commercially wherever its rich medium-brown color is desired.
Special Characteristics and Issues
Site Sanding/ Finishing: This species has a number of alkalines in its chemical makeup which interfere with drying, adhesion and staining. While some oil finishes will dry on this wood,most will not. Also, some neutral oil finishes have reacted with these alkalines and turned red when used with this wood. A water-based finish is the safest bet.
Allergic Reactions: Patagonian Walnut has been known to cause respiratory and contact dermatitis allergic reactions. Care should be taken when exposed to the dust of Patagonian Walnut.