In 1984, Queen's Park hosted two tree planting ceremonies for the eastern white pine, after it was declared the province's official tree that year. The first tree planting ceremony took place on 25 May 1984 by Bob Welch, the deputy premier of Ontario in order to commemorate Arbor Day. The second tree planting ceremony also took place that year at the same location, with Queen Elizabeth II and the Duke of Edinburgh planting two eastern white pines on 29 September 1984. A plaque marks the spot of the tree plantings, and the trees that grew from it.