Mariosousa heterophylla, also called the palo blanco tree (which is also applied to Ipomoea arborescens),[3] palo liso, guinola,[4] and Willard acacia, is a normally evergreen mimosoid plant in the genus Mariosousa native to Mexico.

The Spanish common name translates into 'white stick', defining its peeling white bark.

A compound called willardiine, that acts as an agonist in glutamate receptors, can be isolated from M.

The flowers are like catkins, rod or bottle-brush-like, white or light yellow in color.

It prefers rocky bajdas, slopes and arroyos from 0 to 2,000 feet elevation.