We have a TON of leaves. Lucky for us a hug woods behind us where I drag and dump them. Yes, too many leaves will block new grown of good grass. Some people-----who have not a clue-----about TOO MANY DEEP DROPPED leaves will say, that they help feed the grass, well yes, if a very small amount. But my leaves, if I wait till all trees are done are easy up to mid calf on my leg as I walk through the lawn areas. Right now, my piles in the woods are up to my shoulders, as I would climb on them and roll another tarp on the heap. BTW---as I am sucking up the leaves with the rider, I do it on high, so I am not cutting the grass, but just mulching the leaves. Or using a blower to blow to a pile, depends on where I am in the garden, front or back or side areas. And the trees today, still not done.