Bulnesia sarmientoi is a species of slow-growing deciduous tree found in tropical regions of South America. Trees grow up to 18 meters tall, and are sometimes referred to by the common Spanish name 'Palo Santo', which translates to 'Holy Stick'. The hard wood is sometimes used as timber, and can also be steam-distilled to produce essential oil, which is known as guaiac oil and used in perfumery and soap-making.