This view from atop Mammoth Mountain toward the southeast shows the lakes of lower Mammoth Lakes Basin. The gray area along the edge of Horesehoe Lake (lower right) is one of several areas around Mammoth Mountain where trees were killed recently by high concentrations of carbon dioxide gas in the soil (see closer views of dead trees). Mary Lake (left of center) is the 2nd largest in the basin. The largest lake, Duck Lake, is accessible only by foot and is hidden from view.