Q: We had maple flooring installed five years ago after being told it would be scratch resistant, but our dogs have made a mess of the wood with nail scratches. Is there a way to make the floor look better and keep it that way?

A: Maple is a very hard wood and should be about as resistant to scratches as any hardwood. I'm not aware of any hard flooring that will resist scratching if there is regular traffic by large dogs.

I have heard the same complaint about laminate flooring, which is sometimes described as being highly scratch resistant. I also do not know of any floor finish that won't scratch, although some, like polyurethane, are tougher than others.

If the scratches have penetrated into the wood, the best bet is to have the floor sanded and refinished. Sanding is best done by a professional, although the special tools can be rented at most tool-rental agencies. If only the finish is scratched, you might be able to improve it with a Verathane Renewal Floor Refinishing Kit, which is designed for do-it-yourselfers and requires no sanding.

For more information on the kit, visit www.rustoleum.com/CBGproduct.asp?pid=67.

Keeping the floor free of scratches will be a constant battle if dogs are allowed to roam freely in the house. You can try using thick, washable throw rugs in the areas most frequented by the dogs, but that is not a complete solution. As for carpeting, dogs are almost as hard on it as they are on wood floors. Be prepared for frequent steam cleaning if you try carpeting.

If any dog-owning readers have found solutions to the floor-scratching problem, I'd like to hear from them.

Q: Our asphalt-shingle roof has developed moss in the past few years. Can you tell me of an environmentally safe way to clean it? Can it be pressure washed without damaging the shingles or causing leaks?

A: A very light pressure washing (no more than 500 pounds per square inch of pressure) shouldn't harm the shingles if they are in good condition. This light washing is sometimes used for rinsing after chemical cleaners are used, and it is possible that light washing alone wouldn't remove the moss.

There are so many cleaners now claiming to be environmentally safe, eco-friendly or green that it is difficult to rate them. A cleaner called Roof Cleaner OX is claimed to be "environmentally friendly" and to use "oxygen power" to remove moss and algae from roofs. For more information, visit www.cleanertoday.com .

A cleaner I often have suggested, Shingle Shield Deck and Roof Cleaner, is claimed to not harm plants if used as directed.

It is recommended, however, that nearby plants be soaked with water before use and rinsed afterward. For more information, visit www.shingleshield.com.

When the roof is clean, protect against future moss growth by installing zinc strips near the roof ridge. Information on these strips is also available at www.shingleshield.com

Q: I used Weed B Gon around some shrubs last fall and unfortunately killed the shrubs as well as the weeds. How long must I wait before replanting?

A: It is safe to plant ornamentals and trees a month after using Weed B Gon in an area, according to a spokeswoman for Scotts, maker of Weed B Gon. The soil should be soaked thoroughly with water at least once during that month. When you get new shrubs planted, the best bet is to keep out weeds by using mulch around them. I like pine-bark nuggets, but a number of other types are available at garden-supply outlets and home centers. The mulch also will improve the appearance of the planting beds and help keep water in the soil.

QUICK TIP: Remember when almost everything was cleaned with a damp rag? The fashion these days is to use "wipes" — tissues specially treated to clean various surfaces. I've tried a number of wipes with good results. Most recently, I tested Weiman's Furniture Wipes (www.weiman.com), which did an excellent job on our wood kitchen cabinets, even cleaning the difficult areas around the handles. Manufacturers of the cleaner claim it leaves no wax or silicone buildup. The convenience and efficiency of many types of wipes make them well worth the cost.