What are the differences between a sand-based pitch and a 3G?

A 3G pitch is not as dense as a sand filled or a sand-dressed pitch. The pile is also considerably longer.  As the diameter of a hockey ball is much smaller than a football, a hockey ball sinks further down into the pile of this type of pitch. Consequently, there is much more frictional drag on a hockey ball on this type of pitch which restricts the movement of the hockey ball. The same principle also applies to the hockey stick and therefore makes good stick-work difficult. In addition, because the long pile type of pitch is not as dense as normal hockey pitches the stick can more easily get under the ball causing lifting.