Do raspberries fruit on new wood, then? I know that blackberries fruit on second year wood, so taking them down to the ground would eliminate all fruit for a given year...although it does do an excellent job in rejuvenating a planting. Hmm. This website - http://umaine.edu/publications/2066e/ - indicates it depends on what kind of raspberries you have. I know the ones I have are the thicket-growers, so I'll have to thin them. I wouldn't recommend mowing.