Polyalthia longifolia (Mast Tree) - Richard Lyons Nursery, Inc.The Mast Tree (Monoon longifolium, formerly Polyalthia longifolia), also known as False Ashoka or Indian Fir, is a tall, slender, evergreen tree popular for its narrow, pyramidal shape, making it ideal for privacy screens, windbreaks, and tight spaces. Native to India and Sri Lanka, it grows 30–45 ft tall (up to 60 ft), prefers full sun, and is hardy in USDA Zones 10-11. It is highly valued for its low maintenance, lack of significant pests, and, elegant, drooping,wavy-margined leaves.