Several years back, when I worked for a medium-size daily newspaper in Aberdeen, S.D., I wrote a story about a local fishing group that asked area residents to donate their real Christmas trees for a fish habitat project. The group collected more than 100 trees and used concrete blocks, among other nifty tricks, to submerge the trees in three locations in a nearby lake.

Like many prairie watersheds, the lake had very little "structure" (it was basically a bowl with water in it) and needed a little boost. The goal was less about providing spawning habitat than it was about attracting — and concentrating — sunfish, crappies, bass, walleyes and other fish in a particular area to improve angling. The project — my first introduction to using Christmas trees for wildlife habitat projects — worked well as a so-called "fish aggregator," though for little else.

Once the egg nog is gone and the holiday season officially ends, an estimated 500,000 Minnesotans who purchased real Christmas trees will have to decide how to dispose of them. Environmental groups, state officials and others say old Christmas trees can be reused or recycled for many purposes, though using them in Minnesota waters is strictly prohibited without a special permit from the Minnesota Department of Natural Resources.

"They're not trash and really shouldn't be treated like trash," said Katie Fernholz, executive director of Dovetail Partners, an environmental group based in Minneapolis. "The Christmas season is going to end, but that doesn't mean your tree doesn't have a purpose beyond the holidays. They came from nature and they can go back into nature. Real Christmas trees, which are biodegradable, are the ultimate renewable resource."

Fernholz and others say Christmas tree recycling and mulching programs are a growing trend in the Twin Cities and beyond. Most jurisdictions will collect the trees during regular curbside trash pickup, typically for two weeks following Christmas. Be aware that some haulers may charge an additional fee for the service and may have certain requirements. In addition, many cities and counties have free or inexpensive drop-off locations for Christmas tree recycling. If you can't transport the tree yourself, some Boy Scout troops and other nonprofits offer pickup services for a small donation.

"Depending on where you live, in the Twin Cities or outstate, the services and requirements for recycling can be different, so you should contact your local hauler or the city or county in which you live and find out what's available," said Fernholz. "Mulch has a lot of uses. It's great for gardens because it traps moisture and suppresses weeds. A lot of people will take off the tree branches and chip the tree themselves as a first step in a compost project. One of the most common uses for mulch is for walking trails at parks or even at your home as part of a landscaping project. It's good natural material for trails and paths."

Jan Donelson is the executive director of the Minnesota Christmas Tree Association in Clear Lake, Minn. She said real Christmas trees have other "natural" uses beyond recycling. One example: Use it to create a bird feeder and sanctuary. Donelson recommends putting your Christmas tree in your back yard, on your deck, in your garden or any other location that's "conducive for bird-watching." Fresh orange slices and "strings of popcorn" will help lure birds, Donelson said.

"Christmas trees provide great shelter for birds in the winter, too." she said. "Some people I know take pine cones and roll them in peanut butter and bird seed. The birds seem to love that.

"People in Minnesota and the Midwest in general have a strong tradition of using real Christmas trees, and overall that's good for our environment," Donleson added. "The good news is that a natural tree has many uses after the holidays. They're just beautiful as bird feeders."

Donelson and Fernholz say many communities, private landowners and habitat conservation groups use Christmas trees for sand and soil erosion barriers, particularly along lake, river and stream shorelines.

"Christmas trees can be used as anchors, as a way to stabilize shorelines and reduce erosion into our waterways," said Donelson. "What you're doing is creating a temporary barrier until the natural vegetation takes root. Less soil erosion means better overall water quality."

While real Christmas trees have many uses, Fernholz, who is also a certified forester, said they should never be used as firewood in a fireplace or a wood stove. "Christmas trees get dry very quickly and flare up surprisingly fast," she said. "Conifer resin is also highly flammable. If you decide to burn your tree instead of recycling it, you should have a large property where burning is allowed. You can never be too careful."

Tori J. McCormick is a freelance writer living in Prior Lake. Contact him at tori