What's left over after you
harvest rice: the
stem and the
leaves of the rice plant. On an
acre of rice, this can be as much as three tons of agricultural waste.
Most farmers around the world burn rice straw, because the ash will add nutrients back into the soil.
A recent study in India suggests that farmers could get more return from capturing the methane from burning rice straw than from burning cow dung-- and there's more straw than dung around anyway.
In California, where local air quality standards no longer permit much agricultural burning in the field, rice straw has been put to use to make:
Rice straw can also be tilled under to get the nutrients back into the soil, although not as efficiently as burning. Some California farmers have been encouraged to
flood their post-harvest fields, which helps to
decompose the rice straw as well as provide
habitat for
migratory waterfowl and the
giant garter snake in a state that has severely shrunk its natural
wetlands.
Sources: California Rice Commission, http://www.calrice.org;
The Hindustan Times, <www.hindustantimes.com/nonfram/240699/detOPI04.htm> (29 June 2001)
Carl G. Thelander, Editor, Life on the Edge. A Guide to California's Endangered Natural Resources: Wildlife, BioSystems Books, 1994.