Sunday, January 7, 2024

Plant Story--Lovely Fernbush, Chamaebatiaria millefolium

The plant I call fernbush is an American shrub native to the U.S. west, from eastern Oregon and Idaho south to California and New Mexico. It grows to be about 10 feet tall, spreading to 10' wide. It has leaves with lots of divisions, hence the name fernbush, with a rich spicy scent. The flowers rise in spikes of white flowers with yellow centers. The USDA plants data base calls it desert sweet. An older plant book called it tansybush, because the leaves look like, and smell a little like, the garden plant tansy (Tanacetum vulgare). 

fernbush Chamaebataria millefolium
fernbush Chamaebataria millefolium

Fernbush's scientific name is Chamaebatiaria (in the rose family, Rosaceae). There is an older genus called Chamaebatia, comprised of two species of low shrubs, also in the rose family, which Chamaebataria resembles, consequently the scientific name is intended to say "like Chamaebatia." I find this ironic because fernbush has a much larger range. The two species of Chamaebatia are found only in California and northern Mexico while Chamaebataria is found over most of the far western U.S. and into Mexico. The similarities are strong. Both have compound leaves of many leaflets with a distinctive aroma, and white, open rose-like flowers. DNA studies do not find them to be close relatives within the roses, however. Apparently the botanist that named Chamaebataria already knew Chamaebatia

The name Chamaebatia is derived from the Greek, chamai meaning "low" and batos "bramble." Chamaebatia's common name is mountain misery. Both the scientific and common names refer to the fact that the shrub is dense and very hard to move through. 

There is only one species in the genus Chamaebataria, Chamaebataria millefolium, fernbush, and its native range is only six western states and a bit of Mexico, making it a regional endemic. The species epithet millefolium means "thousand-leaves" referring to the fern-like leaves and also to the leaves of yarrow, Achillea millefolium

In its native range, fernbush grows on tough rocky soils, from cracks in the rocks, and colonizes lava flows. It is a resilient, drought-tolerant shrub. 

fernbush Chamaebataria millefolium
leaves of fernbush Chamaebataria millefolium

The flowers of fernbush are open, five-petaled white flowers with yellow stigmas and stamens in the middle, very much the basic shape of wild roses and other members of the rose family. They make a dramatic showing and attract numerous large and small bees, butterflies, little wasps, and flies. 

flowers of fernbush, Chamaebataria millefolium
flowers of fernbush, Chamaebataria millefolium

Native Americans across the range of fernbush used it externally to treat back pain and venereal disease and internally for stomach cramps. The Ramah Navajo smoked fernbush leaves in a corn husk for hunting success. They also used the leaves to feed sheep and goats.  

Extracts of "Chamae Rose" are sold as natural remedies, for detoxifying, skin rejuvenation, and purifying the blood. There does not appear to be any scientific study of the medicinal claims. In 2003, Tucker and colleagues tested the leaf chemistry and found no compounds with medical properties to differentiate fernbush chemistry from the chemistry of leaves generally, writing, "In conclusion, no essential oil constituent supports the medicinal claims for "Chamae Rose."(p. 574).  As far as I can tell, that remains the scientific last word.

fernbush, Chamaebataria millefolium
fernbush, Chamaebataria millefolium

Chamae rose seems to me an inspired name. Fernbush refers it to ferns, but it is not a fern. Desert sweet is a lovely name but doesn't describe any particular characteristics of the plant. Chamae rose provides useful information since it combines the first part of the scientific name with rose, the plant's family but also a description of the flowers. It is short, distinctive, and descriptive, but it is used for the herbal medicine, not the plant. You could equally call both species of Chamaebatia chamae rose, though their name mountain misery is well-established. Searching on the USDA plants list, fernbush drew a blank because they call it desert sweet. Looking for it on Google, desert sweet I got "do you mean dessert sweet"? and no plants. If you are looking for it in the literature, try all the possibilities. 

Whatever you call it, watch for fernbush. Is it growing in a spot where most plants won't grow? What insects are visiting the flowers? What does the  foliage smell like to you? Its a very interesting and attractive plant.

Comments and corrections welcome.


Moerman, D. E. 1998.Native American Ethnobotany. BRIT Press, Fort Worth, Texas.

Mozingo, H. N. 1987. Shrubs of the Great Basin. University of Nevada Press. Reno, Nevada. 

Nold, R. 2008. High and Dry. Gardening with Cold-Hardy Dryland Plants. Timber Press. Portland, Oregon.

Tucker, A. O. , M. J. MacIarello, J. Hendrickson and J. Davis. 2003. The essential oils of Chamaebatiaria millefolium, Chamaebatia australis, and Chamaebatia foliolosa (Rosaceae) and comments on "Chamaebatiaria multiflorium" and "Chamaebatiaria nelleae" as medicinal plants. Economic Botany 57 (4): 570-575. link (Accessed 1/7/24)
Kathy Keeler, A Wandering Botanist

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