- To control the spread of invasive plants, some have offered a different solution: harvest and sell the invaders into extinction.
- But as some initiatives show, making and selling artisanal products from invasive species can come with social, economic and ecological challenges.
- Instead, some conservationists and researchers say that invasive plants may need to be removed at large scales for industries like biofuel, and not just to make artisanal products.
- While some researchers worry this could incentivize keeping invasive plants around, advocates of commercialization contend that for some species, large-scale economic use might be the only way to control their spread.
In 2009, a village in southern India became a part of a long experiment. The Shola Trust, an NGO, trained the village’s Indigenous communities to harvest stems of a vibrant flowering shrub called lantana (Lantana camara), one of the world’s worst invasive species, and transform them into marketable pieces of furniture. The program had two simple goals: create additional income for forest-dependent communities, and remove a harmful invasive species that was choking the region’s forests.
“But in eight years the furniture business didn’t really take off,” says Tarsh Thekaekara, a wildlife researcher and co-founder of the Shola Trust. “And if you ask how many hectares of lantana got cleared in the process, it would be zero.”
Scientists estimate that there are more than 1,000 species of invasive plants that humans have intentionally or accidentally moved from their native habitats to new regions. In novel environments, many of these invaders have managed to multiply aggressively and outnumber native plants. They haven’t just altered forests, grasslands and other ecosystems, but also created hardships for local communities and cost governments millions of dollars.
Take, for example, kudzu (Puereria montana), a vine originally from Asia, that’s invasive across the southeastern U.S., growing vigorously along forest edges and riverbanks. Or consider the mesquite species Prosopis juliflora, a hardy tree from Central America that has spread all over the world, invading forests, shrublands and pastures.
The problem isn’t just that many invasive plants take over new regions; they can also be incredibly hard to eradicate. Authorities have tried to remove and control their spread in many ways, including uprooting and cutting them, spraying them with herbicides, and even introducing diseases or hungry insects.
“But what I have come to realize is that most of these methods have not worked, at a large scale at least,” says Israel Borokini, a plant ecologist and assistant professor at the University of Montana, who in 2012 published a paper arguing for the economic control of invasive species in Nigeria. Nor do some governments have enough money to manage the weeds, he adds.
So, some NGOs, researchers, local communities and businesses have come up with another strategy: harvest and sell invasive plants to extinction. But can marketing products from invasive species actually help eradicate the invader? Let’s consider lantana.
Selling lantana
In the 19th century, the British began introducing lantana, originally native to Central and South America, to Africa, Asia and Australia as an ornamental hedge. Today, lantana is listed as the world’s second-worst invasive species. And while authorities have spent billions of dollars trying to get rid of the plant, their efforts have largely failed.
In the forests of South India, for instance, lantana continues to take over forests. Since the plant is toxic, its dominance reduces available forage for herbivores. The shrub’s impenetrable thickets also shrink space, both for wildlife to move and rest, and for the local forest-dependent communities to access nontimber forest products and earn their livelihoods.
“It’s not safe to walk in a forest anymore because now there’s no visibility with lantana closing up the grassy understory,” Thekaekara says. Moreover, the densely growing lantana compels wildlife like tigers and elephants to walk the same forest paths as people, increasing the potential for human-wildlife encounters.
To remove the lantana, organizations like the Shola Trust and the Bengaluru-based Ashoka Trust for Research in Ecology and the Environment (ATREE) introduced the idea of artisanal lantana crafts and furniture to Indigenous communities living around South India’s protected areas. But as the organizations subsequently analyzed, several challenges prevented the projects from becoming straightforward win-wins.
First, there was the problem of consistently making lantana products. The communities, for example, already have multiple jobs, from things like agriculture and occasional work with the forest department, to employment on tea and coffee estates, tending to livestock, and selling nontimber forest products.
“The idea that they’re going to leave all of them and take up only one is quite misplaced,” Thekaekara says. “So, they will not actually manufacture furniture like in a factory.”
Quantity aside, it’s also challenging for the communities to consistently make high-quality products that meet industry standards, ATREE found. So, the organization got in touch with Radeesh Shetty, founder of the Purple Turtles and co-founder of Oorjaa, both interior and lifestyle brands. Eventually, Shetty’s team set up a center in Bengaluru where the company’s in-house designers and artisans create prototypes. These are then given to the communities to replicate.
“That way we set very strict benchmarks in terms of the quality,” Shetty says.
Today, Shetty’s companies sell high-quality lantana lamps and furniture crafted by the communities. They also produce large lantana-based art installations for airports and residential and commercial spaces.
Still, selling these products at large scales remains a challenge. There’s the lack of awareness, for instance. Not many people outside conservation circles know about the plant. Moreover, while there are abundant lantana shrubs out there, extracting their stems from the forests in large amounts and making them available at all times of the year is tricky.
“It becomes highly unviable if it’s not available to me all 365 days at demand,” Shetty says.
The lantana stem bundles can’t be cut and stored for use later either, he adds, because the harvested stems need to be processed almost immediately.
“So, now we’re working with multiple NGOs that are able to procure lantana for us, so we’re not dependent on one location,” Shetty says.
Thekaekara’s organization, however, now sees lantana furniture as unviable. They now work with small groups of various forest-dwelling communities to turn lantana into life-size elephant sculptures that travel around the world in high-profile exhibitions.
“It’s about 10 people who work together on one sculpture and they can drop in and out,” Thekaekara says. “So, the sculpture gets produced on time, and there’s a lot of flexibility in how they work and how they split the money between them.”
Auctioning off the sculptures has generated more income than the furniture business. While the first eight years of furniture making earned the communities about three million rupees ($36,000), six years of making the elephants brought them close to 35 million rupees ($420,000), Thekaekara says.
Can commercialization control invasive plants?
As the lantana story shows, invasive species can earn people money.
“Many invasive species have economic use — that’s the reason why many were introduced in the first place,” says Ross Shackleton, a scientist with the Swiss Federal Institute for Forest, Snow and Landscape Research.
But commercially exploiting invasive species to control their spread has largely been experimental, or small in scale.
In Ethiopia, NGOs helped communities set up cooperatives in the 2000s to harvest P. juliflora. One of several variants of mesquite, it was turned into charcoal for the market, while the seed pods were turned into flour for animal feed. Local communities in parts of Kenya and India have also experimented with producing and selling charcoal from mesquite.
Restaurants in the U.S. have featured invasive species like Japanese knotweed (Reynoutria japonica), kudzu and autumn olive (Elaeagnus umbellata) in their menus. In Slovenia, authorities are experimenting with trying to produce paper out of Japanese knotweed pulp. Meanwhile, entrepreneurs in Nigeria are making handicrafts out of the highly invasive South American water hyacinth (Eichhornia crassipes), while those in Kenya are turning the plant into biofuel.
But do these efforts make a dent in reducing the spread of the invasive plants on the ground? There hasn’t been much monitoring to find out, but anecdotally, researchers say no.
In the case of lantana, for example, the infestation in the wild is simply too large: nearly 40% of protected areas in South India have been taken over by the plant. And to make furniture or other lantana products, the communities and companies need only certain straight stems, leaving the rest of the plant untouched. Consequently, lantana continues to thrive.
This is why conservation-based nonprofits like the Shola Trust are now trying to break into industries like biomass energy, where entire lantana plants by the ton could be pulped or burned for fuel daily. This, researchers say, might be the only way to deal with the problem at scale.
To achieve this, Thekaekara says he hopes to create multiple lantana removal units around protected areas, all run by the local communities, who will extract large volumes of lantana, pulverize it on site, and sell it. Then, over about 60 years, you might see lantana go away, he says.
“It’s taken 200 years for lantana to invade to this extent. Taking 60 years to clear it is quite reasonable,” he adds.
But some researchers are skeptical about incentivizing the economic exploitation of invasive species.
“If the goal is to promote local livelihoods and improve the economic situation of poor rural households, then maybe utilization can be approached,” Shackleton says. “But then you will never remove the species totally because you’ll create a reliance on it.”
Thekaekara acknowledges that there can be problems with creating markets for invasive species. But with lantana, he says there’s no other option, especially since the plant is extremely pervasive, and governments don’t have the money to manage it.
“While commercialization and bringing in markets are risky since they are the fundamental drivers of destruction of the natural world, sitting back and saying we’ll do nothing is not an option either,” he says.
However, it’s critical to have certain frameworks in place so that the end goal of eradicating the invasive species is achieved, says Borokini, who continues to advocate for the commercial exploitation of invasive plants in Nigeria.
For instance, it’s important to have the local communities rather than big companies harvest the plants, he says. “That gives them agency and ensures long-term sustainability,” he adds.
At the same time, it’s critical to impress on the people that the economic benefits from the invasive species are secondary goals, Borokini says.
In fact, it’s important to map where the invasive plants are; Thekaekara’s team are using drones and AI to map lantana’s extent, for example, so they can subsequently monitor when and where the weed is cleared, and track if any native trees get felled in the process.
Another key consideration, Borokini says, is to ensure that the place where the invasive plant is harvested from isn’t far from where it will be processed.
“Because if these places are too far from each other, there will be high probability of accidental movement of seeds, which can spread invasive species and become counterproductive,” he says.
It’s also not enough to just think about harvesting the invasive species. Once removed, the land needs to be quickly restored, so that the invaders don’t come back, Thekaekara says. But while most government and NGO budgets get spent on removing invasive species, very little thought and money is allocated to restoration, he adds.
In the end, lantana is such a huge problem in India that its commercialization at large scales might be inevitable, some researchers say.
“It’s going to happen whether we like it or not,” Thekaekara says. “I think we conservationists and researchers have to be at the forefront of it to make sure it happens well; that we put in the checks and balances in place ourselves.”
Banner image: A herd of lantana elephants in London, U.K. Image by Maureen Barlin via Flickr (CC BY-NC-ND 2.0).
Turning Kenya’s problematic invasive plants into useful bioenergy
Citations:
Thekaekara, T., Vasanth, N., & Thornton, T. F. (2013). Diversity as a livelihood strategy near Mudumalai, Tamil Nadu: an inquiry. In Livelihood strategies in Southern India: Conservation and poverty reduction in forest fringes (pp. 49-69). New Delhi: Springer India. doi:10.1007/978-81-322-1626-1_4
Dakhil, M. A., El-Keblawy, A., El-Sheikh, M. A., Halmy, M. W., Ksiksi, T., & Hassan, W. A. (2021). Global invasion risk assessment of Prosopis juliflora at biome level: Does soil matter? Biology, 10(3), 203. doi:10.3390/biology10030203
Borokini, T. I., & Babalola, F. D. (2012). Management of invasive plant species in Nigeria through economic exploitation: Lessons from other countries. Management of Biological Invasions, 3(1), 45-55. doi:10.3391/mbi.2012.3.1.05
Bhagwat, S. A., Breman, E., Thekaekara, T., Thornton, T. F., & Willis, K. J. (2012). A battle lost? Report on two centuries of invasion and management of Lantana camara L. in Australia, India and South Africa. PLOS ONE, 7(3), e32407. doi:10.1371/journal.pone.0032407
Mehari, Z. H. (2015). The invasion of Prosopis juliflora and Afar pastoral livelihoods in the Middle Awash area of Ethiopia. Ecological Processes, 4(1). doi:10.1186/s13717-015-0039-8