The first Friday in April of each year is hereby set apart as Arbor Day for this state, and all communities, state agencies, schools, youth groups and commercial interests are requested to observe the same by encouraging the planting of trees, shrubs, and flowers. Each planting shall benefit the air, water, soil, wildlife and human habitation, and the day should be marked by ceremonies or dedications to remind Missouri citizens of the importance of trees in cities and forests in the state.