by Dr. Sarah Treanor Bois, PhD
Director of Research & Conservation at the Linda Loring Nature Foundation
In our society we tend to idealize and idolize pioneers. Think of those intrepid travelers who went west in the mid-1800s. Or those who explored somewhere for the first time. It takes a certain character to be the first to do something: not only spunk, but grit and determination. If you’re the first to settle in a new area, you have to figure out space, resources, safety. How are you going to survive? We admire these qualities in people who start from scratch, find new territory, put a flag on the moon.
But what about plants?
Pioneer species are typically organisms that are the first to colonize or utilize an area after a disturbance. Think of the first plants to spring up after a hurricane, a tornado, or a burn that sweeps through a forest. Pioneer species, in terms of plants, are the first to colonize barren or disturbed environments, paving the way for the establishment of other species in ecological succession. They are crucial for initiating soil development and creating a more habitable environment for later successional species. It’s a chance for new growth—a resetting of the ecological calendar.
I’ve been thinking about this a lot since the recent construction at the Polpis Road-Milestone intersection. I drive by there frequently between dog walks and trips to Moors End Farm. In the 2 months or so since construction ended, the bike path/road edge had changed from loose dirt to a lush green: amazing given our current drought conditions!
But what is this green? Pioneer species! The most prominent of which is a plant that is actually much reviled: Datura stramonium or Bittersweet Nightshade.
Datura stramonium is the Latin name for a plant that goes by many aliases. Someone once told me that anything with a lot of common names has been used for lots of things by lots of people. That is certainly the case for our Datura or jimsonweed, as it is commonly called in our region. It is believed to have originated in the Americas, but is now found around the world. Common names for Datura stramonium vary by region and include thornapple, moon flower, hell’s bells, devil’s trumpet, devil’s weed, tolguacha, Jamestown weed, stinkweed, locoweed, pricklyburr, false castor oil plant, and devil’s cucumber. For now, I will refer to it as jimsonweed.
Jimsonweed is a member of the nightshade family (Solanaceae), the same family as tomatoes, eggplant, potatoes, tobacco, and peppers, among others. It is highly variable in looks, as if it morphs to suit its surrounding or perhaps to be in disguise. The stem is stout, erect, leafy, smooth, and pale yellow-green to reddish purple in color. The stem forks off repeatedly into branches and each fork forms a leaf and a single, erect flower. The leaves are smooth and toothed, sometimes undulating, sometimes lobed. The upper surface of the leaves is a darker green, and the bottom is a light green. There is enough variability in the leaves that they have sometimes thought to have been different species only to prove themselves to all be Datura stramonium.
Datura generally flowers throughout the summer, so you’ll see it now. The fragrant flowers are trumpet-shaped and white to creamy or violet. During the day, the flowers are sort of rolled up. The flowers open at night (hence the name “moon flower”), emitting a pleasant fragrance, and are fed upon by nocturnal moths, specifically Sphinx moths. Don’t be fooled by the fragrant flower, though. When crushed, the leaves are stinky: smelling sort of like feet. This is a deterrent for most animals, which is why there is little herbivory of this plant.
Flowers are followed by rounded fruits that are walnut-sized capsules covered with sharp spines at maturity. The capsules split open when ripe to release the numerous flattened tan or brown seeds that are similar in appearance to the seeds of a bell pepper. The plants tend to self-seed and can become invasive. The seeds remain viable in the soil for years.
All of this sounds pleasant or at least benign so far. But not only is this plant not native and invasive in some areas, it is also quite toxic. And like many things that are actually poisonous, it also has medicinal uses.
All parts of Datura plants contain dangerous levels of the tropane alkaloids, though the toxicity varies from plant to plant. These chemicals can cause serious adverse effects, including death. But the plant doesn’t want to get you despite what the devil will lead you to believe. These chemical production responses present in Datura function as a natural defense for the plant against dangers like herbivory and various plant pathogens. All that being said, I would suggest just staying away from jimsonweed.
Despite serious safety concerns, people have used jimsonweed to treat asthma, cough, flu, and many other conditions, but there is no good scientific evidence to support these uses. It’s also known to cause hallucinations. The name Jimsonweed supposedly comes from Jamestown, Virginia in the 1700s, where soldiers in the English colony of Virginia reportedly consumed the plant and spent eleven days in altered mental states. Jimsonweed poisoning occurs when someone sucks the juice or eats the seeds from this plant. You can also be poisoned by drinking tea made from the leaves. The psychotropic and medicinal properties of jimsonweed can turn toxic and even deadly with small differences in the amount of plant ingested.
Some Native American stories support that Datura stramonium (aka Devil’s weed) was planted by Lucifer himself, in a night with full moon, in order to take revenge on people.
Whether you call it thorny apple or the devil’s cucumber, I advise just staying away. If you want to see for yourself, however, jimsonweed is common on Nantucket. It’s easily found in areas with freshly disturbed soil and along roadside in piles of loose dirt. It is especially prevalent after some disturbance. For now, you can see it on the Milestone bike path near the turn for Polpis Road.
I have gotten several questions over the years about the jimsonweed and what we should do about it. Maybe the Invasive Plant Species Committee (IPSC) could have a work crew pull it all out? Well, my response has been usually to let it be, and it will sort itself out. That might seem counterintuitive advice given that I actively remove non-native invasive species and am the co-Chair of the IPSC committee. However, in this case, it’s a matter of triage.
We started this article talking about pioneer species, of which jimsonweed is one. But we haven’t yet discussed what happens after initial colonization. In plants, those early colonizers, the pioneers, are later outcompeted. Natural succession takes place in which those disturbed habitats are colonized by other species which can crowd and shade out early colonists. We’ve seen it again and again with jimsonweed: wait long enough and the problem takes care of itself.
Of course, if it’s a plot of land you care about and manage (maybe your own home), you can intervene to speed the process up. Be sure to wear gloves when pulling. Try to remove the taproot. And try to manage prior to the seed pods ripening. Keeping all of that in mind will lead to a higher rate of success.
Other things to keep in mind: jimsonweed seeds last in the soil for years. In one experiment, over 91% of seeds buried at 22 inches survived more than 39 years! Disturbance can always bring it back. If you are initiating a project in your yard, try to ensure that clean fill is used. Jimsonweed seeds, and other invaders, can be a contaminant in unfiltered fill which can exacerbate the problem. Good news is that jimsonweed is somewhat sensitive to drought and so our recent dry conditions may affect them. And they are frost-sensitive, so here’s hoping for a good cold snap in the fall to halt growth and reproduction.
