Cyathea brownii, commonly known as the Norfolk tree fern or smooth tree fern, is probably the largest tree fern species in the world. An endemic of Norfolk Island in the wild it is reported to reach 20 m (67 ft.) or more in height. The broad, lance shaped, bipinnate-pinnatifid to tripinnate fronds can reach 5 m (17 ft.) in length. Stipe is long and has a line of white, stitch like dashes along its length. Rachis and stipe are covered in white-brown and darker orange-brown scales. The trunk can become smooth with age and may display oval scars left from fallen fronds. It is named after the botanist Robert Brown (1773-1858).