Canals and Canal Life
Click on a thumbnail to see a larger image
Season of Rice
Rice growers in coastal estuaries first studied the concept of desalinization in addition to their concerns about irrigation and weed control. Rainfall is captured in enclosed plots and used to desalinate the rich alluvial soil for rice cultivation. The rice growers of West Africa also make use of naturally occurring landscape terracing to give advantage to the crop and water supply. The rice land was typically alternated with pasture grazing and this seasonal rotation provides a natural fertilizer as the cattle grazed on the rice straw left behind. In other regions, farmers who do not have cattle, use crops such as beans to fix the nitrogen of the soil and add nutrients. To this day, the farmers I am working with alternate rice and beans in some of their fields to help with soil replenishment.
The irrigation systems in both styles of farming make use of simple constructions and devices to control water. The sluices or rice boxes provide the flow control. Creation of the checks (embankments) or repair of existing checks and leveling the land is part of each new season’s land preparation. The complexity of this knowledge is not in the actual techniques or devices used, as they are fairly simple designs. The real finesse is revealed in the placement of these tools in relation to the landscape. Judith Carney notes in her book Black Rice that: West Africans had refined an elaborate food production system that displayed acute knowledge of landscape gradient, soil principles, moisture regimes, farming by submersion, hydrology, and tidal dynamics, and the mechanisms to impound water and to control its flow. This knowledge had not existed in the United States prior to the import of millions of African slaves.
The regime of water controls the final outcome: gains or losses. One single half cup serving of white rice requires 25 gallons of water, excluding the water used to cook the rice. Brown rice requires less post harvest processing and only takes 15.7 gallons per half cup serving. California produces approximately 42 million cwt. of rice and when multiplied by a factor of 25 represents an astonishing amount of water. Rice farming has been criticized for the high water usage but when compared to the 40 gallons required for a serving of cantaloupe, or the 80 gallons used for a serving of almonds, rice is not a bad bargain. California is one of the few states where rice production has been on an increase; the USDA report for September 2002 listed a 10% rise. California also has some of the highest yields running 8100 pounds per acre while the domestic average is 6400. The California Farm Bureau’s July 2004 report stated that there were 618,000 acres planted this year and that demand for rice was up. Keep in mind the ratio of 25 gallons to 1/2 cup serving for water usage and you realize that this is a very significant use of land and water.
I have observed an array of wildlife in the fields and irrigation canals including: nesting swallows, beaver, many varieties of shorebirds, varieties of dragonflies, insects, fish, clams and crawfish, along with the ever present egrets and herons. These fields are also a wondrous habitat.
All Images © Patty Arnold 2004. All rights Reserved.