CHT forests being razed for cassava farming, harming biodiversity

Abu Taher, 67, owns 10 acres of lush green woodland in the Pittachhara area of Matiranga upazila in Khagrachhari. Over the past 35 years, this land has been filled with over 50 distinct tree species, providing a home to various mammals, amphibians, birds, and reptiles. Taher occasionally visits this forest to collect fruits and timber.

Visiting the forest in December last year, he discovered that the land was barren. Taher told TBS that all the trees and bushes were cleared by local influentials including public representatives and politicians to make space for cultivating cassava, locally known as Shimul Alu, a woody shrub with an edible root.

The tuber native to South America has been introduced in the Chittagong Hill Tracts (CHT) for cultivation in recent years.

A number of residents of Matiranga and Manikchhari upazilas in Khagrachhari on 27 March said hundreds of acres of forests were razed for cassava cultivation, which is expanding rapidly – nearly doubling in scope every year.

Experts warn that clearing forests for tuber crop cultivation, such as cassava, is not scientifically sound. Such agricultural practices can lead to soil erosion and heighten the risk of landslides, particularly in hilly regions.

They said the cultivators do not follow the specific scientific cultivation systems prescribed by the Soil Resource Development Institute (SRDI) and the Department of Agricultural Extension (DAE) to prevent landslides and topsoil erosion.

According to the SRDI, farmers are not allowed to chop hill slopes. If they do so, rainwater will wash away the topsoil and may trigger landslides.

The SRDI suggests cultivation of such crops in plain land with zero tillage along with creating barriers to prevent soil erosion.

Abu Taher told TBS, "A variety of wildlife such as monkeys, slow loris, civets, various birds and snakes used to dwell on my land but everything vanished after they cleared out the trees and bushes. Many landowners are leasing out their land for cassava cultivation. I did not do it, so they razed the forest forcibly."

Photo: TBS

Jamal Uddin, a Matiranga resident with political ties, is cultivating cassava on a 200-acre land, including that of Taher's.

Jamal acknowledged clearing forests for cassava farming but denied the allegations of taking land by force or without the consent of the owners.

"I have leased these lands. There is no truth to the claims of coercion. Sometimes the caretakers of these lands, in the absence of the owners, handle the transaction. The caretakers take money against the lease," he said.

TBS could not verify Jamal's claim of caretakers taking money for leasing out lands.

Another local influential person named Ahsan Ullah, a former member of the Belchhari Union Parishad, involved in cassava farming, also refuted the allegation of unlawfully managing land.

"Landowners willingly lease their lands to us. We pay Tk10,000 per acre annually, typically from June to June. This year, I have cultivated cassava on 70 acres," he said.

Locals said wildlife in Pittachhara is also at risk because the cultivation of tuber crops, including cassava, is expanding.

Cassava is being grown on 1,200 acres of hilly forest in Matiranga now, which is 600 times larger in volume than when it was commercially introduced by two corporate groups in 2021.

Cassava farming is spreading beyond Matiranga to areas in CHT. Data from Pran Agro Business Limited and Rahman Chemical Limited indicates that they collectively possess 6,600 acres of cassava plantations in the Khagrachhari.

These corporations aim to expand cassava cultivation to 15,000 acres by FY26. Pran Agro plans to increase its Rangamati network to 1,000 acres by then from 378 acres in FY23. Additionally, cultivation in Bandarban started in FY24, with an initial 150 acres set to reach 1,000 acres by FY26.

Mafuz Ahmed Russel, founder of Pittachhara Forest and Wildlife Conservation Initiatives, told TBS, "The rapid spread of cassava cultivation in the CHT is alarming; within the next five years, forests may disappear entirely. This practice is detrimental to our environment, biodiversity, and wildlife, exacerbating the climate crisis."

Md Omar Faruque, additional director (Crop) at the DAE with nearly 19 years of experience working in hill districts, said, "The current cultivation practices of cassava, colocasia, pineapple, ginger, and turmeric in the hills lack scientific methodology. Furthermore, cassava, with its bulky roots, requires extensive soil excavation in hills and slopes during harvesting.

"This causes soil erosion during the rainy season, increasing the risk of landslides in the hills."

While clearing forests and bushes, sometimes farmers use weedicide and burn the bushes, which is also damaging to the environment and biodiversity, he added.

The DAE does not have data about cassava cultivation.

Tapan Kumar Paul, additional director of DAE (Rangamati Region), said, "As cassava gains prominence as a cash crop with nutritional value, and its commercial cultivation expands, our primary concern lies in ensuring that its production adheres to environmentally sustainable practices. It is imperative to minimise soil excavation to mitigate soil erosion, particularly during the rainy season."

Why cultivate cassava

Cassava holds nutritional value in many countries. In Bangladesh, starch powder extracted from cassava is crucial in the textile and pharmaceutical industries, mostly supplied through imports due to demand.

Local companies are pushing for more cultivation to meet market needs, yet domestic production meets only about 2% of demand, totalling over 50,000 tonnes annually.

Harvested between December and February, it takes seven to eight months after planting. Rahman Chemical Limited and Pran Agro Business Limited engage in commercial cassava farming under contract in the CHT.

The Pran cassava project was launched in 2014 through a contract farming initiative. With a $12.5 million loan from the Asian Development Bank (ADB), Pran built a starch and liquid glucose plant in Habiganj in northeastern Bangladesh in 2013. While Rahman Chemical Limited's plant is in Dhaka.

Former UP member Ahsan Ullah said, "Pran gives us around 80% cash in advance for cultivating cassava. For every acre, they gave us around Tk20,000. We have to spend Tk30,000. We can grow around 6.5 tonnes of cassava in every acre and Pran buys it from us." 

Photo: TBS

Several districts in Bangladesh have grown cassava in recent years, including Khagrachhari, Rangamati, Sylhet, Habiganj, Moulvibazar, Tangail, Mymensingh, Jamalpur and Cumilla. However, the highest amount of cassava is being produced in Khagrachhari, according to Pran sources.

Rahman Chemical's Project Director Rezaul Karim told TBS, "We have cassava projects in Khagrachhari district covering over 1,300 acres with 400 acres in Matiranga upazila."

Unregulated cultivation leads to deforestation

According to the Ministry of Environment, Forest and Climate Change, around 31% of the nation's total forest area is in CHT, with 84% natural and 16% planted.

"Various fruit orchards, including mango, pineapple as well as different tuber crops such as ringer and colocasia are destroying the natural hilly forest in CHT," said Abdur Rahman, divisional forest officer of Bandarban.

Nowadays, cassava emerges as another threat in the CHT, he added. 

Several studies indicated that forest coverage in the CHT has decreased dramatically over the last three decades, primarily due to various man-made orchards and the cultivation of tuber crops.

A recent study titled "Carbon Consequences of Deforestation in Khagrachhari of Chittagong Hill Tracts: A GIS and Remote Sensing Approach," published in March 2024 by Khulna University of Engineering and Technology, found that 40.50% of forest land disappeared from 1990 to 2020.

The Bangladesh National REDD+ Strategy (BNRS) noted that the drivers of deforestation and land degradation in hills include shifting agriculture and commercial agriculture.

According to BNRS, "land use after deforestation is around 96.51% for shrubs with scattered trees, orchards, and other plantations (shrubs), shifting cultivation."

According to the data from the DAE, about 39 types of fruits and three types of tuber crops are cultivated in the hill tracts. In the years 2020–21, fruits were cultivated on 2,43,981 acres of land in three districts of CHT and it is increasing every year. In FY23, the land volume was 2,62,453 acres.

Referring to a study of the Soil Resources Development Institute, Md Omar Faruque, the additional director (Crop) at the DAE, said the cultivation of tuber crops such as ginger, turmeric, colocasia, and cassava causes topsoil erosion from 58 tonnes to 80 tonnes per hectare (2.47 acres).

Water sources drying up

Visiting the Pitchhara hilly stream on 27 March, it was observed that the stream, which feeds into the Gomoti River, had almost dried up. Around one kilometre of the 3.5-kilometre stream has nearly disappeared, with the rest of it on the brink of being lost.

Deforestation in the CHT region is causing a crisis for indigenous people, who rely on natural water sources such as waterfalls, creeks, and chhoras, and is further worsened by climate change.

According to local communities, deforestation is the main reason for the water crisis, as the increasing deforestation is drying up the waterways.

Kanchan Mala Tripura, resident of Matiranga upazila, said, "Our home was situated deep within the forests of Matiranga. The introduction of cassava cultivation in our area in 2021 led to the razing of several hundred acres of forest land. As a result, the hilly stream has dried up, forcing us to travel several miles to fetch drinking water."

Another resident, Pori Moni Chakma, said, "We used to rely on forest food, encountering Bengal monitors and wild pigs. However, these animals are now gone."

Professor Dr Aktar Hossain, forest researcher and director of the Institute of Forestry and Environmental Science at Chittagong University, holds corporate companies responsible for the destruction of natural forests in the hill tracts.

He said these forests serve as a natural sponge that preserves rainwater and slowly releases it through the hilly streams on which wildlife and indigenous people rely.

"However, cutting trees and razing hill slopes for fruit and tuber crops cultivation diminishes the watershed of the hills, causing a severe water crisis that endangers both tribal communities and wildlife, forcing them to struggle for survival in the hills and raising a conflict between humans and wildlife," Professor Aktar observed.

A peril for the ecosystem

Experts also noted that the entire ecosystem of the CHT is collapsing, with forests disappearing at an alarming rate due to a lack of guardianship.

Ecology and biodiversity expert Pavel Partha said cultivating mono-crops by destroying the ecosystem in the CHT is a very dangerous practice.

"Commercial cassava cultivation that has been initiated in recent years is very alarming. The ecosystem of the region has already been endangered by the monoculture of teak, rubber, tobacco, eucalyptus, and acacia plantations. So, the invasion of cassava can be disastrous for CHT," he said.

"Commercial mono-crop cultivation can destroy the microorganisms, pollinators, watershed, and carbon absorption ability of the soil of the region. It also hampers the natural forest regeneration system of the region," Pavel explained.

"The commercial cassava cultivation is not only causing a food crisis for the wildlife and local indigenous people but also occupying their territory of movement," he said.

No one is taking responsibility  

Rahman Chemical's Cassava Project Director Rezaul Karim acknowledged that cassava farming in hilly forests causes deforestation but he also said, "We are not harming the environment. We farm comparably plain lands."

Echoing the same, Kamruzamman Kamal, director marketing, PRAN-RFL Group told TBS "We do not cultivate in a way that harms biodiversity, wildlife and forests. We do not cut hills. We cultivate in areas where there is no conflict with biodiversity or wildlife. We are encouraging farmers to cultivate on unused or uncultivated land where there is no need to cut trees and hills."

Hill Forest is managed by the Ministry of Land (represented by Deputy Commissioner).

Md Sahiduzzaman, deputy commissioner of Khagrachhari district, said he had no idea about cassava cultivation in the hilly forest.

"If the indiscriminate fruit and tuber crops cultivation cannot be controlled, the entire hill tracts will be in danger in the near future," warned Professor Aktar Hossain.

Mahbubul Islam, the Principal scientific officer of Soil Resources Development Institute, Rangamati said, "Cassava farmers should follow modern cultivation systems such as Contour Line, Bench Terrace, Across the Hill Slope, Slash and Mulch with Agroforestry, Natural Vegetative Strips to stop soil erosion."

Pavel Partha said, "The cultivation does not benefit the local indigenous people economically, socially, or culturally. It can only maximise the profit of corporate companies. So, the DAE, CHT ministry, forest department, and the planning commission should take into account that the sensitive ecosystem of CHT cannot be destroyed by cassava cultivation. There are many other suitable places in the country for cassava cultivation."

d by cassava cultivation. There are many other suitable places in the country for cassava cultivation."