I did read that they do shed some bark but I think the moles problem should be addressed. They might be making matters worse by trying to make nests in the base. You might want to start treating the lawn with hot sauce, tap water & dawn..............about 2 tablespoons dawn added to 1 qt water and several drops of hot sauce.................if you notice raised spots on your lawn, it most likely moles who did & eat grubs...don't water the lawn too often as they love damp soil.........I would spray the grass first and work my way down to the tree roots. They feed on the ground and then have 6 babies at a time............they don't like hot sauce........