Q I have several large ant hills on my property. Two are in a wooded area; the other is in a flower bed by a small pine tree. I have tried many products that have been suggested by local lawn and garden stores, but nothing has worked. In fact, the ant hills seem to be getting larger. Any recommendations?

A Ants are ubiquitous, making insecticide control only temporary. You probably can't rid your yard of the ants permanently. New ones will recolonize the nests after the insecticide residue dissipates.

And you wouldn't want them gone, anyway. Ants are part of the ecosystem, feeding on other insects and invertebrates. Only destroy those hills that present real nuisances, such as the one in the flower bed.

Target that one with an insecticide labeled for ants. Or try the hot-water folk remedy. Some people swear by it. Pour a quart of boiling water slowly into the middle of the ant hill. Do this three times in one day, then once a day for three days after that.

If that doesn't work, consider moving the flower bed. It's probably easier than trying to remove the ants.

Cookie sheet cleanup Q I've become the owner of vintage Wearever cookie sheets that have been in regular use since 1919. They are yellowed and have blackened areas along the edges and corners. How do I clean them up?

A If cookie sheets are not cleaned thoroughly after use, areas not covered by cookies but coated with shortening will build up those deposits. The deposits aren't harmful and can be removed with an aluminum cleaner, according to experts at the University of Minnesota Extension.

Or you can simmer the pan (a half sheet at a time) in a large pot for five to 10 minutes in a solution of a tablespoon cream of tartar to a quart of water. After this treatment, lightly scour the sheets with a steel-wool soap pad.

Send your questions to Fixit in care of the Star Tribune, 425 Portland Av., Minneapolis, MN 55488, or call 612-673-7032, or e-mail fixit@startribune.com. Past columns are available at www.startribune.com/fixit. Sorry, Fixit cannot supply individual replies.