By Rachel Cywinski
(This article is an abridged version originally appearing on the Native Plant Society of Texas website, November 30, 2020. Thanks to the author for allowing us to reprint her article here.)
The portals of heaven open to announce [that] spring will soon return—that’s the only way that I can describe the aroma of huisache (Vachellia farnesiana) in bloom. Texas A&M University’s Aggie Horticulture website describes this tree as “intensely fragrant.”
For years, I was drawn to this delightful scent but stayed away because of an extreme sensitivity to bee stings. Never are bees more evident than when huisache blooms. Many people also stay away because they fear the thorns.
But one day, looking for emerging native plants as I often do in the neglected historic cemeteries of San Antonio, I ducked under the branches and stood near the trunk. My senses were transported by the unearthly fragrance and the amazing sound of thousands of bees, who were all so entranced by the blooms, that they had no interest in what a human was doing. As I deeply inhaled the fragrance, breezes moved the fine leaves like caresses across my face. I was hooked. Ever since, when I see huisache blooming in the hot and high parts of San Antonio, I look for it each week in places a little farther north or more shaded, until all the trees have bloomed, and spring has arrived.
In the 1800s, some enterprising Europeans imported what we in southern and central Texas take for granted; the macerated blooms of huisache grown commercially in southern France and Portugal are used in some of the world’s most expensive perfumes made in Cannes. Huisache is an “overlooked indigenous plant” that is “very valuable” to urban gardens by fixing nitrogen in the soil and attracting pollinators, said San Antonio City Arborist Mark Bird. “The bees and other pollinators can’t resist.” The Native Plant Project states that the bees particularly need the pollen more than the nectar of this tree and cites it as attracting insects and birds (1).
ISA-Certified Arborist® David Vaughan, one of the charter members of the ISA-Texas chapter, recommends huisache for dry sites. Vaughan listed benefits of huisache as being a pioneer species, fast-growing, maturing to a medium size, fragrant and “gorgeous” with early spring flowers that last a month, with the perk that “compound leaves are small and do not need to be raked.”
Mature trees do have two small barb-like thorns at the base of each leaf, but only the youngest trees have the long spiky thorns to protect themselves. This adds to their attractiveness in urban landscapes, where so many birds fall prey to domesticated cats let outdoors. Birds nest in huisache, according to the Natives of Texas website. Native Plant Project lists it of particular value for white-winged doves (1).
Huisache, a Nahuatl term meaning “many thorns,” is the most common name for Vachellia farnesiana, though it has been called an “acacia” for so long that many will likely continue to remember it as such. The gum derived from the tree is considered higher quality than gum arabic. Other historic and current uses of huisache include medicine, wood, dye, tannin, ink, pottery, glue, toothbrushes, and firewood (2). David Vaughan cautions that, although huisache and mesquite wood have a similar appearance, grilling meat over huisache wood will ruin it.
Other medicinal uses recorded for huisache include: an astringent and demulcent; in treatment of wounds, skin inflammations, and swellings; sore throat, diarrhea, typhoid, stomachic, dyspepsia, dysentery, leucorrhoea, conjunctivitis, uterorrhagia, neuroses, and headaches (3).
The ebony-colored seed pods appear to bulge with numerous small seeds that contain a toxic alkaloid. But that does not prevent them from being invaded by insects as soon as they drop to the ground. If you plan to start huisache from seed, be on the lookout to get the seeds before they are eaten.
Mark Bird has found huisache valuable for controlling erosion and restoring degraded soils. He said, “In some ways the tree can be considered a pioneer species, because it can establish in poor quality soils and lead to future, ‘more desirable’ trees, such as oaks and elms.”
Another ISA-Certified Arborist®, Mark Peterson, concurs with Bird. Peterson, who is a project manager in the Conservation Department of San Antonio Water System, said huisache “is definitely a pioneer species. In certain regions of south and southeast Texas, it is the primary woody species during the first five to thirty years of succession after land clearing.” Peterson has observed that establishment of huisache and mesquite improves soil quality for later growth of hackberry, pecan, mulberry, or oak, particular to site conditions.
Vachellia farnesiana’s native range is considered to cross from southern Florida to southern California, south to northern South America. Vaughan said, “a few grow more north, but seldom survive the occasional very cold winter of the [Texas] hill country.” Huisache is not freeze-hardy, but it is fast-growing and exceptionally drought-tolerant. Peterson says, “The only thing that can seriously affect its growth is over-watering.” In the San Antonio area, one could almost draw a map of the waterways by the presence of huisache, as it is pervasive on the upper banks of streams, creeks, and the river. I think of it as one of those unique plants that so often grows near, but never in, waterways as they are uniquely able to tolerate periods of moisture and yet withstand dry conditions.
This past spring, I happened to be in northwest San Antonio near the place of the most extraordinary annual sight of huisache in bloom. The trees near where I live, between Salado Creek and the San Antonio River, had bloomed a few weeks earlier. And so, I realized this might be the time that trees along creeks in more elevated areas were blooming. Indulging in huisache viewing would really brighten my day, I rationalized—and there were so many trees [from which] I could get whiffs of the fragrance just driving past.
With great anticipation, I found my way to a large roadway that serves traffic exiting and entering a main entrance of a major local employer. I remembered how stunningly the display of golden blooms gleamed all along the upper bank of a stream tributary to Zarzamora Creek and took deep breaths to maintain calm as I rounded the bend, where the setting sun would create such a breath-taking display.
I did not remain calm. I rounded the bend and saw the sunset. There was nothing between us. I pulled over. There were no trees: there was nothing. Where was the “rain of gold” that blooming huisache made in the wind?
As I stared, stunned, another motorist pulled her car in front of mine, and came running back, asking if I was okay. “The huisache [trees] are GONE,” I said to her. She looked at me with confusion.
She asked several times whether I was all right, and I continued to explain the huisache were gone. Her confusion concerned me. Perhaps she might think I was some dangerous person. Then we both changed the conversation. I asked her if she didn’t remember the huisache. Clearly, she didn’t. Then I realized that she just did not know the NAME of the trees. She probably missed them but did not know what they were called. So, I explained it was the trees that always had such beautiful blooms every year, the ones that looked like shining yellow all along this area. I motioned to where the trees had been and said, “It makes me want to cry.”
The woman stared open-mouthed then looked to where the trees had been, then at me, then to the stream bank, as if trying to remember. But she couldn’t.
The woman explained it was very dangerous to stop a car along the roadway, even with flashers on. I asked if it wasn’t between shifts when there would not be so many employees driving. She agreed, and said it was still very dangerous. Even though there were many lanes, there were constant motor vehicle collisions. It was not safe even to be on this roadway.
I told her that I was going to leave. But, I insisted, didn’t she miss the trees that had been there? Again, she seemed confused and unable to place any trees where they had been. She said if I was okay, she was leaving, but that I really needed to get my car off the road altogether; there were too many drivers who ran into people here.
I thanked her. As I waited for her car to move, I began crying in earnest. How many times had the concerned woman driven past the beautiful delicate-looking green of huisache branches dancing over the breeze? Had she passed golden huisache blooms thousands of times and never noticed them?
To me, this was the saddest thing of all.
*For more information about supporting native herbs in the landscape, visit The Herb Society of America’s GreenBridges™ Initiative website.
Photo Credits: 1) Huisache (Vachellia farinesiana) flowers (R. Cywinski); 2) Huisache tree in Alamo Defenders Cemetery in San Antonio, Texas (R. Cywinski); 3) Perfume by Guerlain containing huisache essential oil (public domain); 4) Mature and immature thorns (R. Cywinski); 5) Mature and immature seed pods (Creative Commons, Starr Environmental); 6) Huisache tree blooming and Diana Kersey Art on bridge over San Antonio River (R. Cywinski); 7) Huisache along roadway (R. Cywinski); 8) Huisache bordering the Ecumenical Center of San Antonio, Texas (R. Cywinski); 9) Huisache flowering boughs (R. Cywinski).
Medicinal Disclaimer: It is the policy of The Herb Society of America, Inc. not to advise or recommend herbs for medicinal or health use. This information is intended for educational purposes only and should not be considered as a recommendation or an endorsement of any particular medical or health treatment. Please consult a health care provider before pursuing any herbal treatments.
(1) Native Plant Project. https://www.nativeplantproject.com/. Accessed 8 October 2021.
(2) Purdue University Center for New Crops and Plant Products. https://www.hort.purdue.edu/newcrop/duke_energy/Acacia_farnesiana.html. Accessed 8 October 2021.
(3) Plants for a Future Database. https://pfaf.org/user/Plant.aspx?LatinName=Acacia+farnesiana. Accessed 8 October 2021.
Rachel Cywinski’s professional background is in journalism and mathematics education, including degrees in international business and business economics. She is a native plant enthusiast (with a special affinity for plant identification) and serves as a volunteer for the Ladybird Johnson Wildflower Center in the San Antonio region and is a member of the Native Plant Society of Texas.