A dense turf density effect on water infiltration? Which is true?

• A. Increases
• B. Decreases
• C. Has no effect
• D. Varies with conditions

Answer: (A)

Infiltration rate is strongly influenced by what covers the soil and how the soil structure responds to that cover. A dense turf stand tends to increase infiltration because its extensive root network and higher organic matter content improve soil structure, creating more and larger pore spaces (macropores) through which water can move downward. These pathways reduce resistance to flow, so rainfall water is able to enter the soil more readily rather than running off the surface. The dense turf also shields the soil from crusting after a rain event, helping to keep the surface permeable, and it slows surface runoff, giving water more time to infiltrate. While there are situations where excessive density could lead to compaction or where very intense rainfall might still overwhelm infiltration, the general effect of denser turf is to promote greater water entry into the soil.