PORTLAND, Ore. — Picking a Christmas tree is typically a matter of taste. Is the shape right? Is it too tall? Too short?

Now a handful of growers in the top Christmas tree producing state of Oregon want people to consider another factor — how "green" a tree is. They've created a system to help consumers identify trees grown under certain environmental standards.

"Consumers like to do the right thing," said Joe Sharp, managing partner of Yule Tree Farms and co-founder of the Coalition of Environmentally Conscious Growers. "We are just helping with education."

This is the first year the coalition's program will be seen in the market. More than 200,000 tags will hang on trees, indicating the trees were farmed by the coalition's standards.

To pass muster, a farm must be inspected to ensure that it meets certain standards for managing wetlands, nutrients and pests. Water and soil conservation measures are reviewed, and biodiversity and worker safety are also considered.

The trees are not organically grown, but the coalition says the measures help mitigate some of the environmental dangers of Christmas tree farming, such as excessive use of pesticides and contribution to erosion.

"Now when consumers buy a tree, they can be sure that the tree was grown with the best intentions for the environment in mind," Sharp said.

Only a fraction of the trees on corner lots and at garden centers will bear the tag, however. More than a dozen other tree growers are on a waiting list to be inspected and join the three large growers that are part of the group.

The coalition is hoping to take the tag system nationwide, providing an edge in the multimillion-dollar business.

Nearly 29 million households bought a fresh Christmas tree in 2006, according to the National Christmas Tree Association. Oregon is the top producer in the country.