Climate change

Rice Terraces 101

Sticky or unsticky rice? Always a decision worthy of deep contemplation before dinner.

Interestingly, soil can be sticky or unsticky, too. It all depends on how it’s managed. In the case of the Banaue Rice Terraces in the Philippines, this potentially meant feast or famine!

Far from a spot decision about “what’s for dinner”, decisions about soil management pose much higher, long-term stakes. Armed with their wits and engineering know-how, the ancient Ifugao culture learned to farm this unforgiving, mountainous terrain long ago.

In this setting, a heavy rainfall would ordinarily flush precious topsoil into the valley below. In order to combat erosion, the Ifugao built tiered fields, or terraces. It’s like stadium seating fused with contour farming. As a result, they modeled one of the first sustainable farming practices.

Criss crossing terraces of green blades of rice plants along a mountain edge with mountains behind
The Banaue Rice Terraces (Philippines) represent early efforts to terraform the land for production. A throwback of agronomic practice, they continue to endure as a modern-day marvel and textbook case of human ingenuity – doing more with less – before the advent of mechanization and agricultural inputs. Credit: Tim Durham

The Ifugao wisely recognized the landscape itself as a precious resource. This allowed otherwise unusable land to be farmed productively!

How? Terraces slow the flow of water – the driver of erosion – allowing it to trickle from platform to platform, limiting topsoil loss. It also serves as flood control, giving water a chance to infiltrate rather than runoff. This water sticks around as an underground reservoir for current and future crops.

The lush greenery and topography of the Banaue Rice Terraces is really a marvel. We build terraces like this in the United States with at-risk landscapes. I’ve worked with students at Earth University in Costa Rica to terrace a tropical landscape with simple hand tools (at 5 AM – before the heat ramps up).

Green trees in backgound; terraces of green rice growing along mountainside
Terraces are edged with berms to hold in soil. Credit: Tim Durham

There’s a certain appeal about rice terraces – specifically Banaue’s offerings. The engineering is curvaceous, wrapping around steep hillsides. It speaks to our sense of aesthetics: a stairway to heaven where you can touch the clouds. It’s also a monument to the ingenuity and ethic of an enduring culture.

Postcard perfect, the terraces were carved into the mountains of northern Luzon Island about 2,000 years ago (without laser levelers!). Fast forward to today, and the mountaineer locals still serve as caretakers – harnessing the same deep-seated traditions as their ancestors.

This includes wet rice culture (flooded paddies). Each paddy is dammed by a berm. While there is upland (dry rice) agriculture practiced elsewhere in the world, flooding is preferred at Banaue. Why? The region receives plenty of rainfall that can be channeled to the paddies.

Steep terraces of green rice with mountains behind
Terracing the land in Ifugao allowed ancient cultures to grow rice. Terracing reduces erosion and holds water for crops. Credit: Tim Durham

Rice plants are given a head start elsewhere and transplanted. The field is then flooded to keep weeds at bay. But how do rice plants avoid drowning? They have a unique stem that acts like a snorkel, allowing oxygen to diffuse to the roots. Roots need air to “breathe” too. [While rice can’t survive total submersion forever, the International Rice Institute is developing a variety that can survive an extended stretch underwater – a hedge against extreme weather events at sea level.]

The ability of the local Filipinos to maintain a tradition in the face of a “modern” world is impressive. However, the allure of the big city and pressures of local tourism (ironically) threaten this iconic landmark. Hopefully, the Banaue Rice Terraces of the Philippines will officially take their rightful place along other historic marvels like the Great Pyramid of Giza, The Hanging Gardens of Babylon, and other Seven Wonders of the World (and then there was Eight!).

Answered by Tim Durham, Ferrum College

To read about researchers working in rice production, we recommend these articles:

High protein rice brings value, nutrition

Technology keeps rice fertilizer nice

About us: This blog is sponsored and written by members of the American Society of Agronomy and Crop Science Society of America. Our members are researchers and trained, certified, professionals in the areas of growing our world’s food supply while protecting our environment. We work at universities, government research facilities, and private businesses across the United States and the world.

3 replies »

  1. I have been fascinated with rice terracing after being introduced to one domain of maybe 600 acres deeply hidden in the Borneau tropical forest. To get large areas of terracing in operation an incredible social community must exist.

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