A divining rod is a wand or twig of hazel or willow used especially for discovering metallic deposits or water beneath the earth's surface.

It is described in a book written in 1546 and it has also a modern interest, which is set forth by Prof. W. F. Barrett, F.R.S., the chief modern investigator. The use of the divining rod at the present day is almost wholly confined to water finding, and in the hands of certain persons it undoubtedly has produced results along this line that are remarkable, to say the least. The professional water-finder provides himself with a forked twig, of hazel, for instance, which twig, held in balanced equilibrium in his hands, moves with a sudden and often violent motion, giving to the onlooker the impression of life within the twig itself. This apparent vitality of the twig is the means whereby the water-finder is led to the place where he claims underground water to exist, though its presence at that particular spot was hitherto wholly unsuspected. While failure is sometimes the outcome of the water-finder's attempts, success as often and, indeed, according to the testimony of Professor Barrett,more often crowns his efforts. Various explanations, scientific and other, of the phenomenon have been advanced. Professor Barrett ascribes it to "motor-automatism" on the part of the manipulator of the divining rod, that is, a reflex action excited by some stimulus upon his mind, which may be either a sub-conscious suggestion or an actual impression. He asserts that the function of the forked twig in the hands of the water-finder may be to act as an indicator of some material or other mental disturbance within him. While a hazel or willow twig seems to be preferred by the professional water-finders, twigs from the beech, holly or any other tree are employed; sometimes even a piece of wire or watch spring is used, with apparently as good results.