Haying, tillage, and nitrogen fertilization influences on infiltration rates at a conservation reserve program site

Effect of haying (hayed or not hayed prior to tillage), tillage (no‐tillage, minimum tillage, or conventional tillage), and N fertilization (0 or 67 kg ha −1 ) on surface infiltration rates, Q(h), was evaluated for Conservation Research Program (CRP) site conversion. Soils included Amor loam (fine‐loamy, mixed, superactive, frigid Typic Haplustoll) and Cabba silt loam (loamy, mixed, superactive, calcareous, frigid, shallow Typic Ustorthent). In reference plots Q(h) increased from 1995 to 1997 (27.2 ± 3.2 vs. 36.4 ± 2.9 mm h −1 at 50‐mm tension, 10.9 ± 1.2 vs. 20.6 ± 1.4 mm h −1 at 100‐mm tension, and 4.1 ± 0.6 vs. 10.9 ± 1.1 mm h −1 at 150 mm‐tension) under permanent vegetation. Plots hayed prior to tillage exhibited higher Q(h) when no fertilizer was applied than plots hayed and fertilized or not hayed (31.9 ± 2.9 vs. 23.3 ± 1.3 mm h −1 at 50‐mm tension and 18.1 ± 1.3 vs. 13.5 ± 0.6 mm h −1 at 100‐mm tension). As tillage intensity increased, Q(h) at 50‐mm tension increased (20.1 ± 2.6 mm h −1 under no‐tillage, 25.5 ± 1.6 mm h −1 under minimum tillage, and 30.1 ± 2.0 mm h −1 under conventional tillage). Q(h) did not change from 1995 to 1997 in cropped plots.