If the thought of an entire mountaintop in flames sounds like a nightmare or a Dali painting, you'll be surprised to learn that noyaki, a land conservation technique in Kumamoto Prefecture's Aso county, looks exactly like that from a distance. Local environmental group Aso Greenstock has been teaching the public about noyaki (field-burning) for several years now to ensure it doesn't die out -- and take the Aso grasslands with it.

Aso's landscape was formed by volcanic activity around 50,000 years ago. Forests once covered these 1,000 meter-high plateaus, but cultivation of the area over centuries by humans created the present-day grassy plains.

Culling forests for agricultural purposes is usually associated with environmental destruction. But according to environmental groups, including the Kyushu branch of the Environmental Agency, Aso's well-being today depends on cultivation practices such as noyaki. If the practices are abandoned, the land does not return to its original state; instead, a heavy buildup of susuki (Japanese pampas) grass results. Extremely slow to decompose, buildups of susuki do not return sufficient nutrients to the soil. Soil quality degrades, leading to land erosion after about four or five years, as has been observed at some properties in the area.