Dr. Geewananda Gunawardana
“In time the jungle will swing once more, and then those who care for other things than wealth will wander back to the wet side of the monsoon line, and wild elephants browse where tea is now plucked, antiquaries will unearth the ancient bungalows of the British period, or even of the Scottish which will lie beneath it, and classify the different kinds of bottles found among the ruins, and arrange them in museums. Having both planted tea and arranged the antiquities in a museum, I venture to prophecy that this picture will be realized in very much less than fifteen centuries, perhaps in one-fifth of that, or perhaps in one-tenth.”
These two sentences are from John Still’s 1930 memoir-travelogue, The Jungle Tide, once considered essential reading for Sri Lankan schoolchildren. Still arrived in colonial Ceylon in 1897 and spent nearly three decades as a tea planter, hunter, and archaeologist—interrupted only by a period of convalescence from recurring malaria in the UK. Beyond Still’s Spenglerian outlook, his prophecy carries a powerful and urgent message for modern Sri Lanka: without proactive intervention, nature will reclaim the land through catastrophe. We must begin restoring the forest cover to the upper catchment area—not in fifteen centuries, but right now.
From ancient times to the present, Sri Lanka has invested heavily in extensive irrigation systems. Approximately one-third of the country’s cultivated land is dedicated to rice—our staple crop—engaging nearly one-third of the national labor force. We excel at this production, having achieved self-sufficiency in both ancient times and recent history, albeit inconsistently, due to vagaries of nature.
However, ongoing climatic shifts pose an existential threat to this agricultural lifeline. Global warming and intensified El Niño events severely weaken the ability of our irrigation network to deliver water where it is needed. Major reservoirs across the nation currently sit at just 35.8% of their total capacity, a stark reality that promises to become the norm rather than the exception.
The Science of Degradation
The science underlying this ecological decline is straightforward. The native forest canopy across the central hill country was an indispensable element of our ancient water management system. Within fifty years of British occupation, however, 50% of the forest cover across the central highlands was destroyed. Today, between 95% and 98% of the original, undisturbed primary montane rainforests have been altered or replaced by tea, rubber, and eucalyptus monocultures. This transformation represents a severe blow to the complex irrigation network upon which our national food security depends.
Our ancestors understood what modern land management has forgotten: multi-layered, natural forests are vastly more effective at retaining catchment water than crop monocultures. While agricultural monocultures often function as “green deserts,” natural forests act as giant sponges, stabilizing the hydrological cycle and regulating the release of water into aquifers and rivers. Throughout ancient history, major centers of civilization were positioned in the dry zone lowlands, such as Anuradhapura and Polonnaruwa, leaving the central highland forests untouched to protect the water table.
The primary hydrological differences between a natural forest and a tea monoculture center on canopy architecture, soil composition, and root structure:
Canopy Architecture and Rainfall Interception: Natural forests feature a multi-tiered structure consisting of tall emergent trees, a primary canopy, an understory, and floor shrubs. This layered barrier diffuses the kinetic energy of rain, allowing water to trickle gently down leaves, branches, and trunks to the ground. In contrast, tea plantations consist of uniform, heavily pruned, low-lying bushes. Lacking vertical height or an overhanging canopy, intense tropical downpours strike the soil directly, accelerating surface erosion.
Soil Absorption and Infiltration Rates: The floor of a natural forest is cushioned by thick organic debris—leaf litter, twigs, and decomposing matter—that rapidly absorbs rainfall. Beneath this layer lies porous soil enriched with organic material and macropores formed by insects, earthworms, and decaying root systems. This allows water to infiltrate deeply, recharging underground reserves that gradually feed streams through dry seasons. Conversely, tea cultivation involves heavy foot traffic, tilling, and weed clearance. This continuous activity compacts the topsoil, destroying macropores and significantly reducing the soil’s capacity to absorb water.
Root Systems and Preferential Flow: Deep, diverse, and sprawling root systems in natural forests anchor the soil while creating preferential flow channels—subterranean pathways that direct surface water deep into subterranean aquifers. Tea bushes possess relatively shallow, uniform roots that fail to build these deep channels. Once the shallow soil layer reaches saturation, additional water cannot enter, resulting in heavy surface runoff.
Instead of storing water for gradual release, stripped hillsides shed rainwater rapidly, carving gullies, stripping topsoil, and triggering flash floods downstream. Deforested slopes lose their structural integrity, causing catastrophic landslides. As vast quantities of rainwater run directly into the Indian Ocean rather than recharging aquifers, severe dry-season water scarcity follows. Seasonal streams (oyas) and domestic wells dry up, while the flow of major rivers originating in the central highlands dwindles—a trend set to worsen alongside El Niño cycles. In addition, the eroded soil adds to the silting of reservoirs, reducing their holding capacity, and waterways, causing frequent flooding and degradation of aquatic life. For example, the green labeo or mountain labeo (Labeo fisheri), which is endemic to Sri Lanka, is considered near extinct.
By replacing natural catchment ecosystems with commercial monocultures, the landscape’s natural buffering system has been dismantled. Across tea- and rubber-growing districts, the consequences are stark: rising temperatures, erratic rainfall, frequent landslides, and prolonged droughts put immense pressure on ecosystems that sustain local livelihoods and the national economy.
In the process, the famous decree attributed to King Parakramabahu—“Let not even a single drop of water that falls from the rain go into the ocean without being made useful to man”—has been washed away.
Economic Volatility in the Plantation Sector
Sri Lanka’s current food security remains tightly bound to paddy production. According to Department of Agriculture data, the 2022/2023 season yielded roughly 5.2 million tonnes of paddy (translating to ~3.1 million tonnes of milled rice). Against an annual domestic requirement of 2.4 million tonnes, this generated a national surplus of 700,000 tonnes—roughly a three-month buffer. Yet, a single monsoon failure under worsening climate conditions could easily erase this safety margin.
Concurrently, the economic outlook for the plantation sector is increasingly precarious. Under optimal conditions, Sri Lanka’s tea industry continues to fall short of its historical target of three hundred million kilograms annually. Production costs are escalating, labor shortages are deepening, and global markets increasingly demand verified environmental responsibility and sustainability credentials. Yield losses from aging tea bushes, rising fertilizer costs, and geopolitical disruptions in key export markets compound these pressures. Furthermore, Sri Lanka’s steep terrain prevents the widespread mechanization utilized by competing market producers. The tea sector must pivot toward specialized, high-value teas, i.e., renowned Ceylon brand, over low-grade bulk commodity exports to make this industry economically and environmentally sustainable.
Restructuring the tea industry is often proposed, but these rely on stable export demand—an uncertain assumption under present global market trends. Across North America and Continental Europe, such as Scandinavia, Germany, and Italy, coffee remains the dominant daily beverage; tea is largely marketed as a niche wellness or specialty product. When economically challenged, specialty products are the first to go. Meanwhile, geopolitical turmoil threatens historical tea export markets in the Middle East, and major producers like China and Kenya continue to expand market share over Sri Lanka.
The Way Forward: Regenerative Agroforestry
Sri Lanka faces a fundamental choice. As we are already seeing, our vast irrigation system cannot withstand increasingly erratic weather without forest cover in the catchment areas—the largest natural water-storage system provided by Mother Nature. We cannot allow our historic irrigation infrastructure and food security to collapse under climate stress, repeating the decline that followed the fall of the Polonnaruwa kingdom. Left unmanaged, this path could lead to the catastrophic reforestation John Still predicted, much like what is already occurring in small paddy fields in urban areas.
We cannot afford to leave the future to chance; we must act decisively. We can learn from our ancestors, and transition vulnerable monocultures into sustainable agriculture. The traditional Kandyan Home Garden or Kandyan Forest Garden system is a perfect model. Evolved over millennia, this multi-tiered agroforestry model is widely recognized as a benchmark for climate-resilient, regenerative agriculture. Transitioning economically and ecologically fragile tea and rubber plantations into sustainable forest garden systems offers a viable, lasting path toward securing our national water supply and long-term food security. Such a transition would be a multi-generational project; therefore, having well thought out, lasting plans in place now to safeguard the nation’s lifeline should be a national priority.