Evaluation of Trail-Tube Irrigation Technology

Trail-tubes are lengths of perforated tubing designed to replace individual sprinklers on moving lateral irrigation machines. Water is applied such that the application rate matches the soil infiltration rate (no surface runoff), a reduced line pressure can be used (low energy) and evaporation and wind drift losses are minimized (maximum application efficiency). Trail-tube hydraulic theories were verified in laboratory studies. Field studies were conducted on corn and soybean plots with three trail-tube spacings (1.5, 3.0, and 4.5 m) (4.9, 9.8, and 14.7 ft) and a 40 kPa (6 psi) spray sprinkler. The 4.5-m (14.7-ft) treatment was unsatisfactory because of poor application uniformity and excess surface runoff. Representative coefficients of uniformity for the 1.5-m (4.9-ft), 3.0-m (9.8-ft), and sprinkler treatments were 80, 65, and 96%, respectively. Surface runoff for the 1.5-m (4.9-ft) and 3.0-m 9.8-ft) treatments was about one half of the sprinkler runoff value. Crop yields were not affected by the water application treatments