Stomach contents from Columbian mammoths are rare, since no carcasses have been found, but plant remains were discovered between the pelvis and ribs of the "Huntington mammoth" when it was excavated in Utah. Microscopy showed that these chewed remains consisted of sedges, grasses, fir twigs and needles, oak, and maple. A large amount of mammoth dung has been found in two caves in Utah. The dry conditions and stable temperature of Bechan Cave ("bechan" is Navajo for "large faeces") has preserved 16,000- to 13,500-year-old elephant dung, most likely from Columbian mammoths. The dung consists of 95% grasses and sedges, and varies from 0 to 25% woody plants between dung boluses, including saltbush, sagebrush, water birch, and blue spruce. This is similar to the diet documented for the woolly mammoth, although browsing seems to have been more important for the Columbian mammoth. The cover of dung is thick, and has a volume of 227 m³ (8,000 cubic ft), with the largest boluses in diameter. The Bechan dung could have been produced by a small group of mammoths over a relatively short time, since adult African elephants drop an average of of dung every two hours and each day.