Using the protocol provided by Paul Vendrell of the University of Georgia, I used these to test various crops (Alfalfa, Oats, Winter Wheat, Spring Wheat, Millet, Sudan, etc.) for nitrate test before feeding in the form of hay or grazing cattle on dry feed on their own ranch. The difficult part about using this product is not the strips themselves but making sure you can follow the feed testing protocol beforehand and then use the conversion charts to make the decision to add the feed to your farm. I think they work fine. . There are cheaper products out there, but I have no problem paying $40 for a quality product that could save tens of thousands of dollars in cattle losses if you didn't test it. I also like the fact that it's pretty quick for us instead of sending it to the lab, although I'd like to find a good standardized nitrate solution so I can check the accuracy of the strips over time.
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