Rule 23: Loose impediments.

Definition.

"Loose impediments" are natural objects including stones, leaves, twigs, branches and the like, dung, and worms and insects and casts or heaps made by them, provided they are not: fixed or growing, solidly embedded, or adhering to the ball. Sand and loose soil is loose impediments on the putting green, but not elsewhere. Snow and natural ice, other than frost, are either casual water or loose impediments, at the option of the player. Dew and frost are not loose impediments.

23-1 Relief.

Except when both the loose impediment and the ball lie in or touch the same hazard, any loose impediment may be removed without penalty. Please refer to relevant rule for the move of the ball. When a ball is in motion, a loose impediment that might influence the movement of the ball must not be removed.