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Compilation by Armando Gonzalez Stuart, PhD

Scientific Name:

Flourensia cernua - Asteraceae

Other Common Name:

Blackbrush, Varnish bush, American Tarwort, Hojasén, Hojasé, Ojasé

This plant should not be confused with another herb with a very similar common name in Spanish, also used in Mexican traditional medicine, and known as “Hoja de Sen” (Cassia senna -Fabaceae), which is an entirely different species (McGuffin, et al., 2000).

Where is it found?

This shrubby plant grows wild in various semi-arid regions of the Southwestern United Sates and Northern Mexico.

Parts of the plant used:

The leaves and stems.

How is it used?

In parts of northern Mexico, the leaves and stems are boiled with water (decoction) and taken as a medicinal tea.

What is it used for?

The tea is taken primarily to relieve various gastrointestinal problems, including indigestion, flatulence, and parasites. It is also taken as a purgative (Martínez, 1989).

Tarbush has been found to contain diverse antioxidant and potentially anti-inflammatory compounds (phytochemicals) that inactivate noxious free radicals and therefore may be useful in the treatment of various diseases (Wong-Paz et al., 2015).

Recent data show that tarbush tea is also taken in traditional Mexican medicine as an expectorant for the treatment of respiratory infections, including serious bacterial diseases such as tuberculosis.

The findings from a research study undertaken by Molina-Salinas et al.(2011) supported the popular use of this plant for the treatment of respiratory infections and also suggested that tarbush should be further investigated as a possible treatment for people infected with bacterial multidrug-resistant M ycobacterium tuberculosis strains.

Among various medicinal plants evaluated by Molina-Salinas, et al. (2006) for antibacterial activity, tarbush proved to be especially active against Mycobacterium tuberculosis, the causative agent of this reemerging and sometimes deadly disease. Therefore, the researchers concluded that extracts made from tarbush leaves could be an important source of bactericidal compounds against multidrug-resistant M. tuberculosis.


Safety / Precautions

  • This plant may have important applications for the treatment of various human infectious and parasitic diseases, but it should be used only under the guidance of a professional.
  • Although human intoxications from this plant have not been reported, this speices has been found to be toxic to cattle, sheep, goats, and certain species of  wildlife (pronghorn antelope), especially when other better browsing forage plants are not available (Wagstaff, 2008; Hart et al., 2003; Engle, 2000; González-Stuart, 1990).
  • Avoid taking this plant during pregnancy and lactation.
  • Avoid in patients allergic to ragweed or other species within the chamomile botanical family (Asteraceae).
  • Avoid prolonged treatments with this plant.

Before you decide to take any medicinal herb or herbal supplement, be sure to consult with your health care professional first. Avoid self-diagnosis and self-medication: Always be on the safe side!