The two dozen preschoolers who gathered for an Arbor Day celebration at the Alta Canyon Sports Center may not have understood why a tree was planted, but they knew they wanted a chance to shovel dirt around it.

The 4-foot Scotch pine was placed in the ground just before the youngsters gathered on the grass for a talk about the Friday observance.They listened patiently to a discussion about the origins of Arbor Day and why it is important to recognize the value of trees. They even posed for pictures with Sandy Mayor Steve Newton and 20 tiny blue spruce seedlings.

But when the mayor was handed a shovel and given a wheelbarrow full of dirt to spread around the newly planted tree, the preschoolers suddenly appeared much more enthusiastic about Arbor Day.

Several jostled for a chance to help Newton wield the hefty shovel, and playmates had to be reminded that they needed to give others a chance to dig into the dirt.

That hands-on lesson may have been just the incentive the youngsters needed to get them to plant the seedlings they would be given later to take home for their own yards.

For the grownups at the Thursday morning celebration, one of several held throughout the Salt Lake area this week to commemorate Arbor Day, the effort helped make a dent in the mayor's goal of a greener Sandy through the planting of 10,000 pines.

Students at the Willow Canyon Elementary School in Sandy were scheduled to help beautify their city on Friday, when each grade was to plant a pine tree with help from teachers and parents.

Arbor Day is traditionally celebrated on the last Friday of April, and Gov. Norm Bangerter was scheduled to sign a proclamation Friday that officially designated the day in Utah.

Hawthorne Elementary School in Salt Lake City was the host of a "Trees for Tomorrow" ceremony Friday morning, during which students planned to release hundreds of balloons containing Arbor Day messages.