Rules Of Golf Rule 25-1. Casual Water, Ground Under Repair And Certain Damage To Course.

Interference by casual water, ground under repair or a hole, cast or runway made by a burrowing animal, a reptile or a bird occurs when a ball lies in or touches any of these conditions or when such a condition on the course interferes with the player’s stance or the area of his intended swing.

If the player’s ball lies on the putting green, interference also occurs if such a condition on the putting green intervenes on his line of putt.

If interference exists, the player may either play the ball as it lies (unless prohibited by local rule) or take relief as provided in clause B.