What an ACE Protein Test Actually Tells You (and What It Doesn't)?
In this episode, we unpack what the ACE protein test actually tells us about soil nitrogen — and what it does not. Unlike nitrate or ammonium tests, which capture only a short-term snapshot of mineral nitrogen, the ACE protein test estimates a larger pool of organically bound nitrogen that may support biological nitrogen supply over time.
We discuss where the test came from, why it should no longer be described simply as a “glomalin” or fungal biomarker, and how its value depends on regional context, soil texture, management history, and companion indicators such as soil organic carbon, respiration, POXC, and potentially mineralizable nitrogen.
The key takeaway: ACE protein is not a stand-alone fertilizer recommendation tool. But when tracked over time, especially under cover cropping, reduced tillage, manure use, and diversified rotations, it can help reveal whether a field’s organic nitrogen reservoir is building, declining, or constrained. Read carefully, it helps answer a question nitrate tests alone cannot: how much nitrogen does your soil have to give?
Read the article: ACE Protein [https://soilhealthexchange.com/blog/what-an-ace-protein-test-actually-tells-you]