In skid-equipped helicopters, there is a feeling that doing touchdowns on grass or sod is easier on the aircraft than landing on paved, hard surfaces.
Ain't necessarily so.
While it may be quieter, and appear to have a softer landing on grass than on pavement, consider:
a) the skids don't have a chance to flex as the load is transferred from the rotor to the skids - on grass the skids dig a trench and can't move, so the cross tube can only flex in the area between the mounts (Bell series anyway). This eventually leads to failure of the crosstube, but is also evident in those helicopters doing lots of autorotation touchdowns on grass having the tail lower to the ground.
b) if there is any misalignment between the direction you're pointing and the direction of flight, on grass this can cause the helicopter to be aligned pretty forcefully in the direction of flight - a pretty good cause for things like pylon whirl on the 206 series, as the transmission is free to rock from side to side. On paved surfaces you just slide with some misalignment, which can be easily corrected with pedals if you were worried about it.
c) the grass has a pretty high coefficient of friction, and as the skids are well below the CG, this can cause the helicopter to decelerate more quickly than you may wish- and possibly nose over. On paved surfaces, you decelerate rather gently, but with slightly more noise.
d) grass tends to be more uneven, aggrevating c) above.
The only small problem with landings on paved hard surfaces is that you wear out skid shoes more quickly. Get the improved skid shoes (good for several thousand touchdowns) and learn to accept the noise.
The only times I've ever had problems with the touchdown was on grass. There must be a good reason why Bell Helicopter on does touchdowns at their training school on pavement.