Cessation of cattle grazing has resulted in the reestablishment of wetlands in some streams of the U.S. Southwest. Decades of cattle grazing prevented vascular plant growth in Sycamore Creek (Arizona, U.S.A.), resulting in stream reaches dominated by diatoms and filamentous green algae. Establishment of vascular plants can profoundly modify ecosystem processes; yet, the effects on nitrogen (N) cycling remain unexplored. We exa...