Burrowing chipmunks kept digging bunkers throughout my lettuce beds. Tiring of blocking their access holes only to have them redug the next day, I purchased some 10 foot aluminum gutters and mounted them on the fence above the old bed. Drilling drainage holes in the bottom, and filling the gutters with half potting mix and half compost, I planted a mix of lettuce, arugula and mizuna, watering it every other day.
As you can see from the picture, everything grew quite well, and even the romaine that never seemed to form a tight head firmed up in the gutters. So far no damage from either chipmunks or other pests. When I get time, I'll dig out the raised bed below and line it with wire mesh hardware "cloth". That ought to block the burrowers permanently.
