EUGENE, Ore. — Ken Nagao has come up with a easy way to keep a Christmas tree happy and green.

The Eugene man has been adding vodka to his tree-stand water for the past 15 years. Christmas-tree experts might think Nagao has had too much to drink, but Nagao, an architect, says his holiday cocktail has kept trees alive through Easter.

He tried it after noting that alcohol thins lacquers, and lacquers are often made of tree resin. Tree sap can skim over the cut end of a tree, blocking water uptake, and Nagao figured the vodka might help dissolve the sap.

"It helps dissolve the membrane. The tree starts drinking water almost instantly," he said.

Nagao has experimented with other spirits, but says vodka, specifically cheap Russian vodka, works best. He starts with 1 part water to 1 part vodka, and later switches to 2 parts water, 1 part vodka.

But members of the National Christmas Tree Association are not heading to the liquor store. The trade group of Christmas tree farm owners issued a consumer alert after hearing about Nagao's recipe.

The group says no science backs up Nagao's home recipe, and warns that alcohol is more likely to dry out plant tissue than improve water uptake.

University of Oregon plant physiology professor Bill Proebsting said a university study several years ago found no effect when ethyl alcohol was added to water in the tree stand. Researchers wanted to learn whether consumers could do anything to extend the life of their cut trees, he said.

"Bottom line, we found, was to keep it watered," Proebsting said.

Still, home remedies keep circulating. Some people mistakenly think that adding bleach will help keep a tree green longer, Proebsting said. Others add sugar, a common ingredient in compounds that keep cut flowers fresh longer. It doesn't work with trees, he said.
 

"I'm skeptical but open minded, because biology is a complex and wonderful business," he said.