Reading your results
Add together your NITRITE and NITRATE results for your final result. Consider testing weekly or every other week when tile drains are flowing. Compare tests throughout the season and with other farmers in your area to develop trends based on seasonal changes and management practices.
Factors such as rainfall, soil temperature, soil type, nitrogen application rate and crop uptake will affect your results.
Average result for an Iowa river
Average result for an Iowa lake
Iowa’s drinking water quality standard