Scientists target mess from Christmas tree needles

NEW YORK -- The presents are unwrapped. The children's shrieks of delight are a memory. Now it's time for another Yuletide tradition: cleaning the needles falling off your Christmas tree.

"I'm not particularly worried about it. ... I'll just sweep it up," said Lisa Smith-Hansford of New York, who bought a small tree at a Manhattan sidewalk stand last week.

She likes the smell of a real tree, she said, comparing it to comfort food.

But others do mind. Consumers consistently cite messiness as one of the most common reasons they don't have a real tree, says the National Christmas Tree Association.

Keeping a tree well-watered goes a long way toward minimizing the needle problem. But beyond that, scientists are trying to find ways to make trees less messy and keep them fresh through the holidays.

It's in the genes

Some kinds of trees, such as the noble fir or Fraser fir, are better than others at maintaining moisture and keeping their needles once they're in your house, said Gary Chastagner of Washington State University. But even within a given species, some trees are better than others, he said. Needle retention is an inherited trait: if a tree does well, so will the offspring that grow from the seeds in its cones.

Seeking the champs

At a research station in Puyallup, Washington, Chastagner works to identify individual trees that hold their needles best. He tests branches cut in the fall, which encourages needle loss because they haven't experienced cold weather. He lets them dry, and his team evaluates them after about 10 days, looking for branches that do not shed needles. Needles start to fall off branches of some trees within three to five days when the branch is gently rubbed, even if they aren't dry and brittle. A poor performer may lose all of them within a week.

Good branch, good sign

If a branch does well, it means the tree has good genetics for keeping needles. So growers can seek seeds from those trees to produce seedlings for future plantings. With a federal grant, Chastagner is working with others to identify genetic markers that indicate whether a tree will resist needle shedding. That would make tree-screening much faster and perhaps lead to breeding to produce superior trees.

For now, water the tree

Chastagner emphasizes that homeowners can minimize needle shedding by keeping their displayed trees well-supplied with water. In fact, when he has set up trees for research in early December and kept them watered, some species, like noble and Nordmann fir, have gone three months with only minimal shedding. "The potential is phenomenal," he said.