Pitchforks were long handled forks with two to four prongs at the end. Pitchforks were usually used for forking hay.
The Fourth Doctor watched a peasant using a pitchfork to fork hay killed by the Mandragora Helix. (TV: The Masque of Mandragora)
Toby knocked Arthur Terrall unconscious with pitchfork after he and Terrall fought over Toby's payment for kidnapping Jamie McCrimmon. (TV: The Evil of the Daleks)
The farmer Squire found a Silurian in his barn and threatened it with his pitchfork before he was killed by it. (TV: Doctor Who and the Silurians)
Sarah Jane Smith discovered the Zygon Madra hiding in the upper level of a barn in Tulloch. Madra attempted to kill her with a pitchfork, but missed, and toppled off, impaling itself on some farm equipment. (TV: Terror of the Zygons)