Waru Waru, Where Are You?

A story titled The Lost Art of the Waru Waru was printed way back in Volume 1(2) of Ag-Sieve. Now we have an update. No, waru waru is not a rain dance from remote, exotic Rengaw. Alas they are topographic features of the Peruvian altiplano which, were platforms of soil surrounded by water-filled canals constructed by Inca farmers about 3,000 years ago. By using the waru waru system, Inca farmers of the Lake Titicaca region were able to grow their food quite productively in the face of floods, droughts, and frosts.

Today, technicians from the Centro de Investigacion, Education y Desarrollo (CIED) are assisting local farmers to reconstruct about 10 hectares of the ancient farms, the remnants of which still cover over 80,000 hectares. Current potato yields from these farms are more than double the yields from conventional fields in the region. The system is special in that it requires neither modern equipment nor fertilizers to be productive.

What good is it? In drought conditions, canal water slowly reaches potato roots through soil capillary action. When it's too wet, the furrows drain excess water. Temperature extremes are minimized and soil fertility is optimized (see figure below).

The system's primary cost is for labor to dig the canals that surround the soil platforms. Once the system is in place, periodic maintenance is required, as for any regular ol' potato field in Idaho.

Miguel A. Altieri, Traditional Farming in Latin America, The Ecologist, Vol. 21, No. 2, March/April 1991.