Indiana Cross Roads of America 15 inch finished block by Pearl Pereira. True to its motto, Cross Roads of America” more major highways intersect in Indiana than any other state. The Peony has been the official state flower since 1957. The Tulip Tree with its long-stemmed bright green leaves and yellowish-green tulip like flowers has been Indians official state tree since 1931. Its wood is used to manufacture furniture, plywood, paper, boxes and crates.