“It’s just a Casuarina.”
How many times have I heard people make this comment?
We should be saying, “How fortunate we are to have Casuarinas, because without them many of our more extreme habitats would be devoid of trees!”
Casuarinaceae are highly evolved and unrelated to any other plant species. They are an ancient family of plants which existed long before most other Australian plants.
Casuarina foliage commonly called ” needles” are very thin photosynthetic branchlets. The leaves are reduced to teethed ribs at branchlet nodes. Different species are identified by the number of leaves and the lengths of branchlets.
Casuarinas are dioecious with the male trees turning orange when loaded with pollen. The female trees produce tiny tufted red flowers which develop into woody cones. The seeds are winged and easily extracted from the cone if the cones are stored in a paper bag for a week.
Casuarinas dominate in habitats with limiting conditions such as sandy salty coastal sites, rocky shallow soils, swampy flats and salt lands.
Eco-system services provided by Casuarinas
- Nitrogen fixing through blue green algae root associations
- Roots bind the soil and reduce erosion
- Nesting sites and perches for birds
- Bores and other insects as bird food
- Host for Mistletoe (link)
- Fruit are parrot food
- Seedlings browsed by kangaroos
- Flowers nectar for birds, bees and wasps
- Litter encourages fungi and orchids
- Wind abatement on coast
When next you see a Casuarina celebrate its special place in our environment.
Author: Bev Lockley
Bev is an Australian native plants specialist, with a particular focus on the unique flora of the arid region of the Great Southern and Wheatbelt. Bev is a community activist, amazing teacher, and the initiator and driving force behind the Friends of Piesse Lake and the Katanning Propagators Group.