April 28 -- National Arbor Day
J. Sterling Morton, the originator of the Arbor Day idea, was among the many pioneers moving into the Nebraska Territory in 1854. With the decided lack of trees on the Nebraskan plains, Morton made it his cause to plant trees, not just for beautification but also to preserve the soil. He encouraged civic organizations to join in the effort, proclaiming the first Arbor Day in 1872. Today, the most common date for observances is the last Friday in April, although many states celebrate it whenever conditions there are best for planting trees.