John Burroughs (April 3, 1837 - March 29, 1921) was an American naturalist, proponent of the American conservation movement and one of the most important practitioners of the American literary genre, the nature essay. Many of Burroughs' essays first appeared in popular magazines. He is best known for his observations on birds, flowers and rural scenes, but his essay topics also range to religion, philosophy, and literature. Burroughs was a staunch defender of Walt Whitman and Ralph Waldo Emerson. His achievements as a writer were confirmed by his election as a member of the American Academy of Arts and Letters. The Complete Writings of John Burroughs totals 23 volumes. He enjoyed good physical and mental health during his later years until only a few months before his death when he began to experience lapses in memory and show general signs of advanced age including declining heart function. He died in 1921 at the age of 83.