Editorial Team
Publication Date
September 11, 2023
Mayamitu Neupane, GPJ Nepal
Hom Prasad Acharya uncovers a dead goat on his propriety in Birtamod municipality. The goat — and dozens of others over the years — died of poisoning; he suspects an invasive plant, Mimosa diplotricha, is the culprit.
JHAPA, NEPAL — When Hom Prasad Acharya’s goats, all 70 of them, died in three days, the livestock farmer from Jhapa district in eastern Nepal was terrified. The 51-year-old had just started rearing goats, and the deaths meant there was nothing left of his fledgling business. At first, he thought of selling the meat, but given the goats had died mysteriously within hours of each other, he wasn’t sure if it was edible. Over those three days in 2020, Acharya buried most of the goats in an empty piece of land near his house.
However, the deaths kept irking him. Before they died, like several other farmers, Acharya had taken the goats to graze in the dense Nichajhoda forest nearby. So he hauled the remains of one of his last goats in a car to the veterinary hospital and animal services center in the district. There, the resident veterinarian conducted a basic autopsy and informed him that the animal died from ingesting a toxin. The veterinarian, Dr. Binay Kumar Shrestha, told Global Press Journal that he is certain the goat died of poisoning, but since the facilities in Jhapa don’t have an advanced chemical lab, he couldn’t confirm which toxic substance had caused the death.
Acharya says he took a sample of the weed that the goats had fed on for the veterinarian to check. Shrestha identified the plant as Mimosa diplotricha, a thorny shrub that now grows all over forests in Jhapa and is known to locals as “ulta kanda” (reverse thorn). Acharya says his worst fears came true. As the former president of Birtamod Stock Farmers Group, an informal collective of 18 farmer groups, he had often heard of cattle dying from eating this weed that grows haphazardly all over the forests around Jhapa. He had not envisaged how violently toxic it could be until he witnessed the deaths of his entire herd.
The Divisional Forest Office in Jhapa confirmed that they have so far recorded 5 hectares (12 acres) of ulta kanda growth in the forests of Jhapa. Mimosa diplotricha is not native to Nepal; it originates from the tropical Americas, particularly Central America, South America and the Caribbean region. While locals say they started noticing the plant in Nepal’s forests roughly 20 years ago, the species was identified as Mimosa diplotricha only in 2019.
The plant’s rapid spread is emblematic of the damage exotic species have wreaked on forests and natural ecosystems around the world. An exotic species is a plant or an animal that does not naturally occur in a location and encroaches on local resources used by native flora and fauna. In the case of plants, experts say exotic species often turn invasive, growing faster than native species and aggressively soak up water and a majority of nutrients from the soil, destroying trees and plants that grow naturally in that particular landscape. In some cases, as with Mimosa diplotricha in Nepal, the consequences of invasive species growing unchecked are grave and involve death and disease.
A weed that kills cattle
A ulta kanda plant typically grows up to 3 meters (10 feet) tall and its stems are covered in sharp thorns that curve backward, each between 3 and 6 millimeters long. In Jhapa, the plant is found almost everywhere now — near riverbanks, bogs, barren land, roadsides and the Jalthal forest that sprawls across 6,100 hectares (15,073 acres) in the district.
Several studies have pointed out that Mimosa diplotricha could be toxic for livestock. Deaths of water buffaloes, sheep and cows after consuming the weed have been reported across the world, but the exact nature of the plant’s toxicity has yet to be conclusively determined. While some studies suggest that the plant in its entirety could be toxic for herbivores, others suggest the toxic reaction could depend on the plant’s stage of growth and the animal’s physiology. In Nepal, however, with the exception of a handful of studies based on secondary sources, no government agency has investigated livestock deaths or the impact of ulta kanda on cattle.
Two ward presidents — community representatives elected by locals — who spoke with Global Press Journal about the issue say locals have complained for at least five years about the mysterious deaths of their livestock.
Krishna Prasad “Aviral” Kharel, president of Birtamod municipality ward No. 7, says at least 40 people in his ward in just the last two years have complained that several of their cattle died as a result of consuming ulta kanda in the forests. These farmers had insured their livestock, and Kharel says that he did not know what to do except assist them in claiming the insurance. “In my municipality, which has 1,800 households, roughly 1,000 cattle have died in the past eight years from ulta kanda poisoning,” Kharel says.
Sitaram Bhattarai, chairman of Arjundhara municipality ward No. 3, says that at least 600 cattle there have died from eating ulta kanda in the past five years. “I don’t know what to do,” Bhattarai says.
Kharel says it is difficult to spot the plant amid the ample greenery of the forest. Workers from his municipality tried spraying it with weedkiller when it could be identified, but it didn’t seem to have had any effect.
Acharya, who lost 500,000 Nepali rupees (3,816 United States dollars) because his goats were not insured, now goes around manually uprooting the weed whenever he spots it.
But despite the general panic among locals, spokespersons for three key government agencies — the local municipality office, the district livestock services office and the Jhapa-based Agriculture Knowledge Centre, a wing of Nepal’s agricultural ministry — say they have received no complaints of any livestock deaths.
A study, but few answers
In March 2022, researcher Bharat Babu Shrestha’s team from Tribhuvan University’s botany department in Kirtipur, Kathmandu, published the only study conducted by Nepali authorities so far on ulta kanda. The researchers from the public university studied the weed in the Sundar Nichajhoda community forest area in Birtamod ward No. 7, with the support of the Ministry of Agriculture and Livestock Development’s Plant Quarantine and Pesticide Management Centre.
According to the study, this species so far has been spotted only in Jhapa and Morang districts in Nepal. The study reveals the only way to battle the rapid growth of the plant is by uprooting and destroying it before it starts flowering and producing seeds. It explains that 15,000 to 20,000 seeds can be produced per square meter area of these plants, and the seeds can survive in the soil for up to 50 years. In some countries, a bug called Heteropsylla spinulosa has been introduced in the plant’s habitat and has managed to destroy it, the study reports. However, in Nepal, no such action has yet been taken.
While the study mentions that mimosine, the chemical found in the weed, can be poisonous, Shrestha says that the team did not chemically test the weed in a lab. The information was compiled from other international studies whose researchers have been credited in the final published paper, he says.
The lack of information and awareness about the impact of the weed has left farmers to depend entirely on the observations of their peers when it comes to ulta kanda.
Tek Bahadur Katuwal lost six goats in less than an hour. Katuwal remembers that he had taken the goats to a nearby riverbank a few days before the Hindu Dashain festival in October 2022. He spotted a patch of bright green weeds, and he led the goats to it. Within minutes of eating the weed, which he now realizes was ulta kanda, the goats started shrieking and rolling on the ground. He watched in horror as they died in the next few minutes. His neighbors in the Morang district later got together and raised 12,000 rupees (90 dollars) for Katuwal and his family so that they could celebrate the religious festival and also recover some of their losses.
“Farmers from other villages have often come to inquire about the death of my goats over the past year,” Katuwal says. His issue, like that of many of his peers, is the lack of knowledge about ulta kanda or ways to deal with it.
Prem Ghatani, of Arjundhara municipality ward No. 3, borrowed nearly 130,000 rupees (991 dollars) to buy three buffaloes. They died within four days of being brought home. Ghatani says they died after grazing on ulta kanda, which grows all around his home.
Despite Shrestha’s study declaring that there is a significant and rapidly growing infestation of ulta kanda in Jhapa and Morang districts, senior crop protection officer Maheshchandra Acharya, from the Plant Quarantine and Pesticide Management Centre in Lalitpur city, says that apart from a few attempts to raise awareness, no concrete action has been taken on the issue. Considering the infestation involves various aspects governed by different ministries and departments — animal welfare, agriculture, forestry — there seems to be confusion regarding whose responsibility it is to deal with the issue.
While government agencies struggle to find answers, locals have to risk livestock deaths and venture into newer territories in the forest, armed with unverified knowledge about ulta kanda.
Dilliram Prasain, a cattle farmer from Birtamod municipality ward No. 7, says they are forced to take the risk because finding grass for cattle to graze on is becoming increasingly difficult in Jhapa. And the reason behind this is another invasive species that has swept across the Jalthal forest: Mikania micrantha, or what locals call “pyangri lahara.”
Losing natural forests to invasive vines
Unlike ulta kanda, pyangri lahara is not toxic for cattle, and animals don’t eat the plant anyway. But over the past few years, pyangri lahara has crept over large swathes of the Jalthal forest, shrouding the grass that the cattle feed on. According to the Divisional Forest Office, pyangri lahara has spread over 1,000 hectares (2,471 acres) of land in the Jhapa district. Each year, the forest department estimates that pyangri lahara growth doubles or triples in expanse, threatening the biodiversity of Jalthal, which hosts more than 150 species of trees and plants.
Jeevan Prasad Pathak, assistant divisional forest officer at the Divisional Forest Office in Jhapa, says that the growth of plants like sal (Shorea robusta), sisau (Dalbergia sissoo), bot dhangero (Lagerstroemia parviflora), kathar (Artocarpus heterophyllus), badahar (Artocarpus lacucha) and latahar (Artocarpus chama) has fallen by at least 20% in the Jalthal forest due to the growth of the invasive pyangri lahara plant.
The native plants are critical to the health of the local ecosystem and the life and livelihoods of forest-dependent communities. Sal, sisau and bot are used for timber and firewood. Kathar, or jackfruit, is an important food commodity. And latahar is a rare, native endangered species. “Once Mikania attacks a forest, reproduction of the native plants decreases, the forest’s quality degrades, and it also affects biological diversity,” Pathak says.
Farmer Chiran Paudel, from the Haldibari rural municipality, says that years ago, pyangri lahara could only be spotted on riverbanks and in parts of the forest. Now, it is everywhere. “It has climbed up coconut, mango and banana trees, and on reaching the top, the Mikania leaves covered the canopy, preventing the trees from bearing fruit. No vegetables also grow in the area where this weed is spreading,” he says.
Although precise statistics are unavailable, the pyangri lahara infestation has affected at least 5 hectares (more than 12 acres) of agricultural crops, according to the forest division, and surged from the eastern fringes of the country to the west.
Lilanath Sharma, program coordinator and botanist at ForestAction Nepal, a nongovernmental organization, says that local communities have tried uprooting, burning, slashing and pouring herbicide on the weed. However, nothing could stop the plant from growing back and swiftly carpeting the forest, covering native saplings and grass.
Mayamitu Neupane is a Global Press Journal reporter based in Nepal.
TRANSLATION NOTE
Sunil Pokhrel, GPJ, translated this article from Nepali.
