Beginning their journey on a diet of salt pork, lard with flour, and Indian meal, Meriwether Lewis, William Clark, and the other members of the Corps of Discovery went on to taste nearly everything the West had to offer through necessity rather than choice. Wrestling their keelboat and pirogues up the Missouri River required tremendous physical effort, and it also required up to nine pounds of meat per day for each soldier to maintain strength, so hunting quickly became an important duty. In the short-grass prairie of the High Plains, the abundance of buffalo, elk, deer, and wild fruit led William Clark to call this region a "Land of Plenty." The expedition killed its first buffalo nearby on August 23, 1804, and also found an abundance of elk and white-tailed deer in this region. The Corps of Discovery entered what is today South Dakota when the wild fruit was ripening, and black raspberries, black currants, and wild plums soon became an important addition to the expedition's diet.