1864?-1943 20thcentury africanamericanfarmers africanamericans africanamericanscientists agriculturalconservation agriculture agriculturists autobiography biography black carver comicbooks conservationists environmentalconditions environmentalprotection general georgewashington graphicnovels history historytuskegeeinstitute inventions inventors juvenileliterature juvenilenonfiction nonfiction peanuts politicalandsocialviewscarver research scientists southernstates strips technology tuskegeeinstitute unitedstates