Sex and the Cassowary Trees

Casuarina and Allocasuarina species
Family: CASUARINACEAE
I noticed my first casuarinas of the season in flower this week.





Strictly speaking, the above photo doesn't belong on this blogsite, whose subject is plants of our local basalt soils, as this red flower is on a  thready-barked she-oak, Allocasuarina inophloia a lovely shaggy-barked species found on granite soil at Crows Nest. The female trees were decked out with their tiny red flowers, waiting for the wind to blow pollen across to them from the brown catkin-like flowers on the nearby “he-oaks”.

It is the time to be on the lookout for the flowers of all our local species.
I checked my forest she-oaks (Allocasuarina torulosa) when I got home, and found that I had missed the flowering (they tend to be an early species), and the little seed capsules were already forming. All four of them have turned out to be females, fertilised by males on (developer-owned) nearby bushland.
As our suburbs spread out and take over the bush, our forest she-oaks are disappearing. Some of them, I have discovered, fall victim to people who are unaware that there are different species of Casuarina, and mistake our very inoffensive, modest-sized locals for some more aggressive species. (Casuarina glauca is a plant native to coastal catchments. It doesn't belong on the Darling Downs, and is proving to be distressingly invasive, with very difficult-to-control suckers, where it has been planted.)


Casuarinas of all kinds are favourite trees of mine, with their “cassowary-feather” branchlets that catch the wind and sing.

Best of all, to my mind, are the forest she-oaks, with their fine weeping foliage that is red in the springtime (mine are just beginning to show red now), and their corky, fissured trunks (pictured at right). The exaggerated ridges of these twenty-year-old trees will modify with time but the trunks are always pretty.