Boulder Lake to Poison Canyon and Lilypad Lake Professional Review and Guide
"On this trip you’ll probably hear coyotes yelping at night, see deer grazing in the meadows around sunrise or sunset, or even spot a bear. Raptors, including golden eagles and several species of hawks, soar above a wide, lush basin covered with stands of forest and pockets of meadow around Lilypad Lake, with Ycatapom Peak (which supposedly means “leaning mountain” in Wintu) as a marvelously textured backdrop and a reasonable challenge for peakbaggers. A series of terraces with flower-covered meadows and several pristine ponds lead south to Thumb Rock, a huge granite hump on the ridge above Parker Creek. You will likely see few other people around Lilypad Lake and even fewer on the terraces below Thumb Rock. Perhaps the name “Poison Canyon” discourages visitors; the climb up the steep ridge south of Boulder Lake is certainly a deterrent, as are the swarms of mosquitoes in early summer."