The flower of Datura wrightii
Datura wrightii, also known as sacred datura or jimsonweed, is a representative of a group of plants that mean many things to many different people. Fans of Carlos Castaneda will know of this genus from Castaneda’s hallucinatory accounts of his journey through the teachings of shamanism. Ethnobotanists will know of the traditional uses of Datura spp.–that a number of species were used by people of every continent (except Antarctica) to perform religious rituals, poison enemies, and treat the ill. Gardeners will know Datura wrightii as a deer-resistant species with exceptionally large and sweet-smelling white trumpet flowers that bloom at night. ER doctors who have had to treat overdosing experimenters will be familiar with the toxic effects of this genus. Sandy’s photo beautifully captures the spiritual, aesthetic, and even dangerous characteristics of this species.
Another group that has investigated Datura, and specifically Datura wrightii, are entomologists and insect ecologists. One particular area of interest for this group is the way that Datura wrightii‘s trichome dimorphism affects insect herbivory. Some jimsonweed plants feel velvety, because they have short, non-glandular trichomes (which are fine outgrowths or appendages on the plant, in this case hairs). Others feel sticky, as they have glandular trichomes that secrete acyl sugars, thus providing resistance to herbivorous insects. In a 2005 article published in Ecology, Daniel Hare and James Smith compared herbivory and seed production of Datura wrightii plants expressing either the “sticky trichomes” or the “velvety trichomes” trait. Hare and Smith conclude that producing glandular trichomes reduces seed production in the plant’s first year, and that the herbivory resistance conferred by the glandular secretions never fully compensates for this initial setback. Although the glandular trichome gene is dominant, under the study conditions examined by Hare and Smith, it did not confer an overall evolutionary advantage.
One of the most studied aspects of Datura wrightii is this species’ relationship to the hawk moth (Manduca sexta). Adult hawk moths pollinate datura flowers, but also lay their eggs on the plants. The hatched larvae then consume datura leaves. This mutualistic yet also antagonistic relationship has interested many an entomologist (for more details, consult Bronstein et al’s 2009 article, Reproductive biology of Datura wrightii: The Benefits of A Herbivorous Pollinator (PDF)). A particularly amusing facet of this relationship is that some people have noticed that hawk moths become intoxicated after wallowing in sacred datura pollen. Rather than quickly visiting one flower and moving onto the next, some hawk moths arrive before the flower opens, and once allowed inside, will submerse themselves deep inside the corolla, beating their wings frantically until completely covered in pollen. It appears that datura’s alkaloids affect moths and humans alike. Learn more about these “jimsonweed junkies” via the nonist.
In our explorations of the Utah desert, we have come across Datura spp growing near the ruins of the Native American groups that lived there centuries ago. We talked about sleeping near the plants to influence our “dreamtime”…never did though.
Love these babies… and Joshua Tree, which is a great place to roam.
I’ve long been intrigued by this plant and its appearance in the Gene Autry song, “Back in the Saddle Again.”
I’m back in the saddle again
Out where a friend is a friend
Where the longhorn cattle feed
On the lowly Jimson weed
Back in the saddle again
If it is indeed poisonous, why is the doofus letting the cattle eat it?
In California, I was taught that the non-native Datura stramonium was properly referred to as jimsonweed, whereas our native Datura wrightii was referred to as Sacred Datura or Bur Apple….
Chuck, cattle will avoid it unless it is the only thing available to eat: Cornell University’s Department of Animal Science – Plants Poisonous to Livestock – Datura spp.
Our son introduced me to this plant and one with purple flowers. I’ve lost the purple one and last year gathered no seeds so what comes up this year will be from the parent plant.
Ha! So the moth thinks it’s flying!
Beautiful photo and fabulous write-up, as always. Thank you!
What a wonderful picture! I can almost see the scent wafting from the opening flower.
My current plant was labeled D. inoxia by the friend who gave it to me ; I’ve grown every wild-growing kind whose seeds I can collect & am too lazy to key them out. None have the fascinating yellow glow, nor do any in the CalPhoto collection, and I’d love to know if it’s from the setting (or rising) sun or an unusual plant.
Mystery addicts may remember several books whose plots hinge on the use of Datura, to kill or stupefy. In one story then new freeze-dried instant coffee was laced with the somewhat similar looking seeds of Datura.
Berton Roueche (“Annals of Medicine” writer for the New Yorker for many decades) enthusiasts may remember the story of the family who showed up in the ER hallucinating. Clever detective work turned up the culprit: tomatoes grafted onto Jimson weed in hope of increasing frost-resistance & general vigor. “My neighbor’s been doing it for years,” the man and gardener of the family said. But the neighbor took the leaves off the Jimson weed and the inadvertent poisoner’s plants were big bushy Daturas with a branch or two of tomatoe growing from them… The story’s one of those collected in “The Medical Detectives,” too.
When I was teaching Nature Study at Cal State East Bay’s Contra Costa campus I took the class to the denuded cattle acreage next to the campus. It was leased out & destined for parking & MacDonald’s and the like, so grazed to the dirt — except for D. wrightii and Doveweed (Eremocarpus setigerus at the time, now lumped with Croton) The few dozen cattle left were being fed but still destroyed every other bit of plant they could reach. (Ideal CA Ground squirrel habitat: bare hilly ground; the squirrels gathered seeds on campus & roadsides & took them into the acreage so it was great for snakes, hawks, vultures, & the occasional Golden Eagle — in case you wonder why we did field trips there. Also some protected pockets were fantastically rich in small vertebrate species.)
Doveweed also has narcotic seeds and I’ve seen doves feeding on it (the dove clan are such junkies!) but haven’t happened to catch them harvesting Datura seed. I wonder…
If anything in my garden speaks “summer” to me, it is this moon flower. It thrives in summer’s heat, repaying us with a bounty of flowers scented like water lily. They are fun to pick (extremely short stem)in late afternoon and allow to open on the dinner table in a vase in front of unsuspecting guests who will be treated to scrolls that magically unfurl during the meal to trumpets with flaring flowers the size of saucers. I can pretend that summer is not ending, but the datura is a realist. As the daylight shortens and the temperature drops, production drops off too. Allow some seeds to mature and fall and you will have a new crop of volunteer seedlings the next spring. If they are mulched or otherwise protected, I have noticed that some will survive the winter.
Over here, across the pond, we have Datura stramonium, Thorn Apple, as a garden escape. In Norfolk it is said to be especially associated with former smithies. Blacksmiths were said to give a leaf to horses being shod to keep them calm.
The Daturas can be extremely invasive and are listed as a noxious weed in many states, some provinces, and many countries.
I was first attracted to this plant as a food source for moths, but no longer grow it…
actually, not a ‘food source’ for moths, but of a means to attract more moths, and so then attract bats to my garden….