Compiled by Helen Carter
Introduction
Endemic to southwest Western Australia, the iconic Jarrah is known for its dark red hardwood timber used in furniture making and building. In the bushland this hardness makes it more resistant to insect attack that, along with its ability to thrive in a variety of soil types and environments, increases its chances of living for a long time.
In early colonial days it was logged and exported across Australia and the world, notably in Sydney and London, to pave roads replacing the noisier traditional stone cobbles. In WA it was logged around Kalamunda then transported by horse drawn wagons to Masons Landing on the Canning River in Cannington. From there it was floated down the river to Fremantle port for export.
Growth habit
Heights of 45 metres are reached when growing in deep soils and higher rainfall areas of the southwest. Usually it is a single trunked tree with a canopy of dark green leaves, conical shaped buds and barrel shaped fruits. In Jirdarup bushland it presents mainly as a coppiced tree due to being cut down or burnt in previous times – hence being recognised as a resprouter.
Who calls this home?
Over 400 species of animals and insects call the Jarrah home! In the Jirdarup Bushland, the rich nectar from its flowers provides moisture and food to many species of animals including birds, wasps, flies, ants and bees. Its mature fruit provide an important protein source for cockatoos and other parrots.
Birds use the tree for nesting, while insects, lizards, skink, geckos and other reptiles find shelter and feed under its bark and in crevices. Bats also find the deeply fissured bark and crevices an ideal place to call home.
And there’s more!
Fallen leaves, branches, nuts, bark, flowers and dead wood are broken down by wood eating termites and other insects, as well as fungi and slime moulds. This replenishes the soil and provides nutrients to create perfect conditions for the germination of new Jarrah trees and environments for other biota to flourish. The shade it provides is also a welcome relief on a hot summer’s day.
We need to protect it
Good bushland hygiene is desperately needed. The Jarrah tree is susceptible to Jarrah Dieback (Phytophthora cinnamomi) a type of water-borne fungus that attacks its roots and blocks the water carrying vessels, causing it to ‘dieback’. We need to stop the spread into the bushland by using the boot washing facilities at the Etwell St, George St and Baron Hay Court entrances. In 2020, the Friends of Jirdarup noticed several dying Jarrah – you can read the report here.
So next time you admire the beauty of this magnificent tree in the bushland, think about its role in the ecosystem and its vast contribution to the health and sustainability of many living creatures that all make this a beautiful place to be.
Further reading
French, Malcolm (2012). Eucalypts of Western Australia’s Wheatbelt.
McCrum E & McCrum J (2023) The Nature of the Jarrah Forest. Vivid Publishing Fremantle WA.
Powell R & Emberson J (2023). Growing Locals Gardening with Local Plants in Perth. Western Australian Naturalists’ Club, Inc.
Holliday I & Watton G (2017) Gardeners Companion to Eucalypts (4th Ed). Reed New Holland Publishers.
