Q Lately I've seen a mangy-looking female cardinal at my Roseville feeder. She's missing neck feathers and has a scraggly crest. She's sometimes accompanied by a male without any feathers on its head. What's going on with these birds?

A Every fall, there are reports of "bald" cardinals. Some experts think the feather loss is caused by feather mites. Their theory is that birds use their beaks to control the mites on their torsos, but because they can't reach their heads with their beaks, the mites take over, causing feather loss.

Others say this kind of feather loss can happen during the bird's fall molt, but instead of losing a few feathers at a time, as most birds do, some birds lose all their head feathers at once.

Whichever is the cause, your cardinals almost surely will produce new head feathers soon.

No-mess seed Q I'm just about ready to quit feeding birds altogether. The shells pile up under the feeders, kill the grass and make a big mess. I enjoy the birds, but don't know how to cope with this.

A You can have both grass and birds by making one simple change: Feed with shelled sunflower seeds.

The shells of black-oil sunflower seeds contain a mild toxin that kills grass. But if you use shelled sunflower seeds, there's no toxin and no mess under the feeders.

Shelled seeds, either whole or in pieces, are more expensive, but they're worth it because you won't need to replace the dead grass or regularly move your feeders.

This column is prepared from questions that Val Cunningham, a St. Paul nature writer, receives via e-mail. To have a question answered in this column, send it to valwrites@comcast.net.

High-energy foods

Q I put out suet all summer and the birds really went for it. But I'm wondering if I should cut them off so they will eat more bugs.

A Most of us think of suet as a winter treat, but birds relish the calories it provides all year, especially in summer when they're spending so much energy raising their young. Some birds even carry bits of suet to their nestlings. However, raw suet can melt in the heat. If you put it out when the weather's warm, it's best to use pressed cakes made of rendered suet.

Birds live such challenging lives that I'm in favor of doing whatever we can to make things easier for them. So go ahead and keep providing suet for your back-yard birds.

Another source of quick energy is unsalted, shelled peanuts. You can use them on a platform feeder or in a wire mesh tube. Plenty of birds, including woodpeckers, chickadees, nuthatches and blue jays, love peanuts.