The first tree introduced into America was the peach, by the Spaniards in the early 16th century. Pears, apples, cherries, quince, and plums followed in 1638 and again in 1663. Survival of man was foremost. The first tree shipped from America was the arbor-vitae, to France, before 1550. Indians used tamarack for thread, shagbark hickory for fresh cream. Peaches were planted by them in quantity. The first native trees planted by the Colonists were sugar maple, red oak, catalpa, and American elm. Those used for building and furniture were white oak and black walnut. American elms were of early historical significance; one was the "Liberty Tree," under one there was a signing of a peace treaty with the Indians by William Penn, and under one George Washington took command of the Continental Army. The first botanic garden was started by John Bartram near Philadelphia in 1728. The first commercial nursery, the Robert Prince Nursery in Flushing, New York, began in 1737 and existed until 1869 through four generations, included an extensive variety of fruits and ornamentals. The first organized street tree planting program occurred in Philadelphia in 1750. Fairmount Park, Philadelphia, is the oldest park in America. Men of importance regarding trees: Mark Catesby who introduced Nyssa sylvatlca, Asimina, etc.; John and William Bartram who found Franklinia alatamaha; Johnny Appleseed who started extensive apple plantations; Andre Michaux who discovered Cladrastis lutea; Joseph Howland who found Tsuga canadensis pendula; William Hamilton who planted the first fruit tree varieties; Dr. George Hall who first introduced trees directly from the Orient; and Dr. Ernest H. Wilson who explored and introduced plants extensively. There are many cultivars of recent essence including the Merrill magnolia, seedless and fruitless honeylocusts, Bradford pear, etc.