Stylidium productum and Stylidium graminifolium

Trigger plant

Family: Stylidiaceae

Stylidium is a fairly common perennial herb found in heath and open forest on sandy soils.

Three species of Stylidium grow in Lane Cove National Park. Two of these, Stylidium productum and Stylidium graminifolium can be easily confused. S. graminifolium and young S. productum have leaves arising from the base, especially the young S. productum. When older, the grass-like leaves of S. productum occur in tufts scattered along and at the end of sprawling stems. The third species is Stylidium lineare, which has leaves less than 1 mm wide and 2 cm long, growing in a dense tuft.

The flowers are pink, in a terminal spike at the end of a tall stalk.

The common name Trigger Plant comes from the plants' method of pollination. A tube containing the style and 2 anthers is usually bent back below the flower. When an insect lands on the centre of the flower, the tube jumps up to strike the insect, covering it with pollen which it then takes to another flower. The "trigger" usually resets itself within about 20 minutes.

Stylidium productum flowers from November to January. Stylidium graminifolium flowers from August to January. Stylidium lineare flowers from September to December.