Practices that combine stubble management for snow catch and contour-ripping for snowmelt
infiltration have potential to increase water infiltration and soil water storage. Our objective
was to investigate sod lapping to improve water infiltration into frozen soil. Infiltration
studies on frozen soil were conducted at sites near Pendleton, Oregon (silt loam soil), and Culbertson,
Montana (sandy loam soil). Ripping was performed with a single chisel or parabolic subsoiling
shank at 6- to 8-m intervals on the contour to a depth of 0.2 to 0.3 m. Final infiltration
rate on the sandy loam averaged 11 mm h-1 on the rip treatment and 1 mm h-1 on the no-rip
treatment even when the soil was frozen deeper than 0.6 m. On the silt loam soils, when the average
depth of frozen soil was 0.14 m, average final infiltration rate was 28 mm h-1 on the rip
treatment and 2 mm h-1 on the no-rip treatment. There were no treatment differences on the silt
loam when the soil was frozen 0.35 in. Soil condition at the time of ripping determined the effectiveness
of tillage to improve water infiltration; there was little benefit from ripping a dry pulverized
soil because loose soil flowed into the rip and obliterated the rip path. Desirable macropore
structure on loose soil was achieved by deferring ripping until the soil was frozen. Infiltration
measurements show that soil ripping has potential to increase water infiltration and consequently
decrease water runoff, and if used in conjunction with stubble management to maximize snow
trapping, may increase overwinter soil water storage
