Infiltration is a very complex process. Rock fragments affect infiltra
tion by their presence in the soil matrix and on the soil surface. Pro
cedures for quantifying soil and surface rock fragments are reviewed.
Within the soil the physical properties and hydraulic properties that
affect infiltration are shown to be influenced by rock fragments. Phys
ical properties discussed are bulk density, porosity and water content
. Hydraulic properties that affect infiltration are water retention, s
aturated conductivity and unsaturated conductivity. Rock fragments on
the soil surface have been reported to both increase or decrease infil
tration rates and amounts.