I am just wondering what is the most common way to install a new bed in existing lawn area that is primarily heavy clay. First, is it adviseable to use Roundup to clear the turf or a sod cutter? I've heard so many different things. Also, in a heavy clay situation when planting a shrub bed, would you dig out several inches of the clay and raise the bed or just leave the clay and raise the bed? Basically, I'm just wondering to what extent is it necessary to amend the soil in areas like this. Thanks.