A holiday tradition born of frustration, the annual painting of evergreens with "pink ugly mix" to discourage tree thieves, continues at Cornell Plantations, the university's arboretum, botanical gardens and natural areas where the repulsive-but-biodegradable goop was invented more than 15 Christmases ago.

Plantations gardener Gerardo Sciarra had grown weary each December morning of showing up for work and finding jagged stumps where majestic evergreens had lived the day before. Most vulnerable were specimens near roadways where lazy louts could hack and haul, oblivious to the value of the trees, many of which were planted in memory of loved ones.

Fences and guards were inappropriate for an institution of Cornell Plantations' size and inconsistent with its character, Gerardo knew, so he sought a way to make the trees temporarily unattractive. His solution is, literally, a solution:

• 1 gallon of water
• 15 ounces hydrated lime (not agricultural lime)
• 4 ounces Wilt-pruf (or other commercially available tree protectant)
• 2 ounces red food color

Mix ingredients in a large pail or other container. Stirring the solution is extremely important, both before and during use. Apply with a broom or large brush. Conditions at time of application should be dry and above freezing; otherwise the mix freezes before it dries and slides off the tree.

Cornell Plantations workers apply the pink ugly mix to susceptible trees after the Thanksgiving weekend. The substance, which enhances the soil and does not damage trees, lasts through December -- unless the season is unusually rainy -- then dissolves with exposure to the elements. Ugly Mix is credited with saving dozens of Cornell trees over the years.

More food coloring may be added to make the mix really pink, Sciarra notes. Additional amounts of tree protectant may be used.

And for once, the gardener says, neatness doesn't count: The sloppier the uglier, and the uglier, the better.