Arbor Day

A day set aside for tree planting. Each state has a specific time in the year for this purpose designated by the National Arbor Day Foundation. These dates are carefully chosen to correspond to the time of year most favorable for the survival of newly planted trees and shrubs. Arbor Day is always on a Friday to allow K-12 schools across the country the opportunity to participate in this useful activity.

Links
  http://www.arborday.org/