Irrigation data have been collected from all farms and ranches in the census of agriculture since 1890. Of the 2.13 million farms and ranches in the United States, approximately 14 percent are irrigated. The acreage of

irrigated U.S. farmland is 52.6 million acres; that's a 3 percent decrease from the 54.2 million acres irrigated in 1998.

Since 1998, sprinkler system use rose 8 percent - to 50.5 percent of the total market - while gravity flow systems fell 15 percent - to 43.4 percent. Drip/trickle systems account for 5.6 percent of the market and subirrigation systems have slipped to just 0.5 percent.

Although sprinkler systems were used on just more than half of the irrigated acres in the United States, the primary methods of irrigation vary widely by state. California, the leading state in irrigated acres, used gravity flow systems on 60 percent of its irrigated acres and sprinklers on only 20 percent of its irrigated acres. In Nebraska and Texas, the next highest ranking states, sprinkler systems were used in up to three-quarters of their irrigated acreages.

Other key findings of the irrigation survey:

• More than 62,000 farms with irrigation spent $657 million on hired and contracted labor for irrigation activities.

• Farmers and ranchers spent $1.13 billion on irrigation equipment, facilities and land improvements. Eighty-five percent of that money went toward replacements or new expansions, with the vast majority receiving no public funding assistance.