Frank Zybach, farming near Strasburg, Colorado, patented a "Self-Propelled Sprinkling Irrigating Apparatus" on July 22, 1952. Mobile towers carried a pipeline in a circle around a pivot, and sprinklers on the pipeline distributed the water. In 1954, rights were sold to Valley Manufacturing at Valley, Nebraska, starting an industry with several manufacturers, mostly concentrated in Nebraska. Pivots were the first system to automatically irrigate a variety of crops, soils and field sizes. Today, over 110,000 pivots irrigate 14 million acres in the U.S. while efficiently using soil and water resources.