| 1.3
Check fields after irrigation to evaluate uniformity of irrigation
water applications (through use of a ball probe, visual inspection, etc.).
1.4 Analyze irrigation
water quality periodically, and credit nitrates (NO3-N) in water to crop
requirements. Nitrate test results can be calculated by simply multiplying
parts per million (ppm) NO3-N by 2.7 lbs/AF (pounds per acre foot) times
the amount of effective water applied (in feet) to the crop, to determine
pounds of nitrogen (N) per acre applied in the irrigation water. |
Sample Calculation: Irrigation Water
N Credit
30 inches of water applied containing
7 ppm NO3-N
7 ppm NO3-N x 2.7 N/AF
x 30 inches applied/acre
12 inches/AF
= 47.25 lb N per acre
|
