Exchangeable K did increase with glyphosate application. This could be because the glyphosate formulation was a K salt. Exchangeable K increased proportionally to the amount of added glyphosate and K. The large majority of K added with glyphosate was able to be extracted and detected as exchangeable K. Therefore, it seems that soil fungi did not rapidly incorporate K into microbial biomass K, nor transfer K to nonexchangeable K sites. If soil fungi are transforming exchangeable K to plant unavailable forms of K, the transformation is not proceeding rapidly enough to overcome the rate of K addition by glyphosate or from other soil K pools.