He is best known for playing the role of the Third Doctor on Doctor Who from 1970 to 1974 and also the title scarecrow in the television children 's comedy series Worzel Gummidge . Pertwee is best known for his role in the BBC science fiction television series Doctor Who , in which he played the third incarnation of the Doctor from 1970 to 1974 , and as the title character in the series Worzel Gummidge .