Despite the language barrier, Warming's influence on the development of ecology is remarkable, not the least in Britain and the USA. The British ecologist Arthur Tansley was extremely influenced by reading ’Plantesamfund’ (or rather the 1896 German edition). Reading the book made him jump from anatomy to ecology. Tansley used the book as textbook in a university course as early as 1899. Similarly, Warming's book was decisive in forming the careers of North American naturalists like Henry Chandler Cowles. Cowles' now classic studies of Lake Michigan sand dune plant communities were directly inspired by Warming's studies of Danish dunes. Also Frederic Clements was much inspired by Warming when starting to working with succession, but more by Oscar Drude in formulating his concept of vegetational climax in his 1916 book.