Warning on use of nitrogen strips

Nitrate test strips can be used for a quick test for soil nitrate levels. However improper storage of the strips can give erroneous results. In particular, the strips must be kept as dry as possible. Even a little bit of moisture causes the strips to be non-functional.

In this photo, the same soil was tested with all 4 strips. However, the top 2 strips were stored in a plastic bag, while the bottom 2 strips were stored in the original…