I have perennial beds that are mounded. Each year all of the large wood chips are found in piles along the edges as they are washed down the hills with every rain and snow over the winter. This is a real pain. I don't want to put stones in but I am beginning to think that this is the only mulch that will stay in place. I read that the shredded mulch might hold better. Is that true. We didn't put in the mounded beds as they were already there when we purchased this house and they are quite beautiful.