Ashburn, GA, (very close to Heaven!) | We are running just about all low pressure systems, averaging less than 50 psi, with either rotators or sprays on drops. Our average pivot is about 1600 feet long and about 1100 gpm, and we get most of that to the ground, probably in the 95% range.
There has been a lot of work done to support drops, and drops are the standard in Georgia. (BTW, Georgia ranks second in number of pivot systems and fourth in pivot acres in the US.) While visiting in Mississippi and Arkansas last winter and spring, I saw that most of their systems are sprays on top. They have a lot of research to support that these are very comparable to drops in efficiency.
Impacts on top and 85psi would be low in efficiency down here, and very expensive to apply. A typical pivot well in my immediate area is 300 feet deep, and some of them have 3208 Cat engines running them, while burning 8 gallons of diesel per hour. I just ran numbers on one that is low pressure, 1696 feet long with end gun that takes 94 hours to put out one inch of water. At $2.40 per gallon, that equals $8.70 per acre inch, which is plenty. I had another grower run numbers himself on his high pressure system, similar size, and he came up with about $12 per acre inch. This looks like a year that we are going to be applying between 12 and 15 inches of irrigation for a good cotton or peanut crop. We have to gain efficiency whereever we can find it..... |
Pivot Wing loss
