Warren

Warren National Park is a 3,006-hectare protected area in the karri forest zone of southwestern Western Australia, situated between Pemberton and Northcliffe on the Darling Plateau. The park protects outstanding karri (Eucalyptus diversicolor) forest including the Gloucester Tree — one of the world's tallest fire lookout trees, a 60-metre karri with a spiral staircase to a fire lookout platform at the top — a famous attraction since 1946. Warren is adjacent to Beedelup National Park and forms part of the Pemberton-area conservation reserve system. The park is managed by DBCA.

Warren National Park supports the karri forest fauna community. The critically endangered western ringtail possum depends on mature karri and marri trees for food and hollow-bearing trees for shelter. Forest red-tailed black-cockatoos nest in large hollow karri trees and feed on karri seed capsules. Short-beaked echidnas, brush wallabies, western grey kangaroos, and quendas are common. Tiger snakes and dugites inhabit damp creek valleys. The Warren River, rising near the park, supports marron in cool, clean-water reaches.

Karri (E. diversicolor) reaches exceptional stature in Warren, with trees exceeding 60 metres — among the world's tallest hardwood forests. Marri (C. calophylla) and jarrah are associated forest trees. The understorey includes karri oak (Allocasuarina decussata), native wisteria (Hardenbergia comptoniana), and diverse orchids, ferns, and spring wildflowers. The park's high rainfall supports lush understorey growth. Riparian zones support paperbarks and sedges.

The park sits on the southern Darling Plateau — deeply weathered Archaean granite-gneiss. Karri forest grows on deep, clay-rich soils derived from moist, weathered granite in valley positions. Laterite caps ridge surfaces. The Warren River rises on the plateau and flows south into the Southern Ocean near Augusta.

High-rainfall warm temperate Mediterranean climate (1,000–1,300 mm annually). Cool, foggy winters and warm dry summers. Fog drip contributes additional moisture to the forest. The karri requires these high moisture conditions — it is geographically restricted to the zone receiving more than 900 mm rainfall annually.

Warren National Park lies within Bibbulmun Noongar country. The Pemberton area was heavily logged for karri from the 1890s, with major sawmill operations transforming the landscape. The Gloucester Tree karri survived because it was selected as a fire lookout tree.

Warren National Park was proclaimed to protect a significant karri forest area containing the famous Gloucester Tree. DBCA manages the park with prescribed burning to maintain forest structure and reduce wildfire risk. The Gloucester Tree has been a popular attraction since the late 1940s.

The Gloucester Tree — a 60-metre karri with a climb-at-own-risk spiral steel peg staircase to the canopy fire lookout platform. Only 20–30% of visitors who start the climb complete it. The Big Brook Arboretum is adjacent. Bushwalking trails through karri forest. Spring wildflower walks.

Located 2 km east of Pemberton on Pemberton-Northcliffe Road. Car park and basic facilities. DBCA park entry fees apply for the Gloucester Tree area. Pemberton provides accommodation, restaurants, and services.

Western ringtail possum recovery requires old-growth karri with hollows. Climate change-driven rainfall reduction is already causing canopy dieback in the driest parts of karri range. Phytophthora cinnamomi dieback threatens proteaceous understorey species. Fox predation on possums requires control programs.