DubTrub, can't argue with those numbers
. My Cub was an L4 with a filter on the cold air but, as normal, no filter on the hot air.
Regarding the grass, I was thinking about clumps of cut grass rather than the odd bit.
PS We used Arizona red dust as it was available in a range of different, closely controlled, grain sizes. The fine stuff was good for polishing out scratches in sunglasses when mixed with a bit of water!