With the weather playing tricks and threatening to dump ice and snow on the greens of our golf courses, it might help to familiarize yourself with some "winter" rules.

Rule 25. Abnormal ground conditions and wrong putting green.

"Casual water" is any temporary accumulation of water on the course that is visible before or after the player takes his stance and is not in a water hazard. A ball is in casual water when it lies in or any part of it touches the casual water.

Snow and natural ice, other than frost, are casual water or loose impediments, at the option of the player. If it's cold enough for frost to form on the grass, you do not get to remove your ball from that clump of love grass. Dew and frost are not casual water.

It's not too often that Sandhills golfers have to worry about frozen lies, but there is an icy situation that could come into play even in 90-degree heat.

Manufactured ice, such as the kind you may use to keep a "cool one" ready during a round, is an obstruction. If someone playing ahead of you has dumped some ice cubes from a cup or cooler and your ball comes to rest in or near enough to it for interference in striking the ball, the ice is an obstruction.

You are entitled to remove the ice, which is regarded as a "movable obstruction." You don't have an option of dropping away from the ice without penalty, and killing enough time between shots for the ice to melt is an option that may incur the wrath of the foursome behind you.

If the ball happens to move while the ice is being removed, it may be replaced without penalty.

"Ground under repair" is any portion of the course so marked by order of the rules committee or so declared by its authorized representative. It includes material piled for removal and a hole made by a greenskeeper, even if not so marked.

Stakes and lines defining ground under repair are obstructions. The margin of ground under repair extends vertically downward, but not upward. A ball is in ground under repair when it lies in or any part of it touches the ground under repair.

But don't get confused here. Grass cuttings and other material left on the course that have been abandoned and are not intended for removal are not ground under repair unless so marked. So don't think that just because your ball has stopped on top of a pile of cut grass in the rough you're entitled to a free drop. Play it as it lies or take an unplayable drop with penalty.

As for all the environmentally sensitive areas on courses these days, just accept your rotten luck -- or shot -- take the penalty and play on. The committee may make a local rule prohibiting play from ground that has been declared in that category.