The Cycad Sago is June's plant of the month.
Botanical Name: Cycas revoluta
Cycads are an ancient group of seed plants called gymnosperms (naked seed). They first appeared and have existed for approximately 300 million years, appearing before there were dinosaurs, existing alongside them, and perhaps being eaten by them. Unlike the dinosaurs, however, the cycads never became extinct; they are still with us, although they are not now as abundant or diverse as in their Mesozoic hey-day.
Habitat and Distribution
Cycas revoluta is native to southern Japan including the Ryukyu Islands. It is one of several species used for the production of sago, as well as an ornamental plant. It grows in warm temperate and subtropical regions. Of all the cycads, revoluta is the most popular in cultivation.
This very symmetrical plant supports a crown of shiny, dark green leaves on a thick shaggy trunk that is typically about 20 cm in diameter, sometimes wider. The trunk is very low to subterranean in young plants, but lengthens above ground with age. It can grow into very old specimens with 6–7 m of trunk; however, the plant is very slow-growing and requires about 50–100 years to achieve this height. Trunks can branch several times, thus producing multiple heads of leaves.
The leaves are a deep semi -glossy green and about 50–150 cm long when the plants are of a reproductive age. They grow out into a feather-like rosette to 1 m in diameter. The crowded, stiff, narrow leaflets are 8–18 cm long and have strongly recurved or revolute edges. The basal leaflets become more like spines. The petiole or stems of the sago cycad are 6–10 cm long and have small protective barbs.
As with other cycads, it is dioecious. This means a plant group that includes distinct male and female parts. Pollination can be done by insects.
The pith contains edible starch, and is used for making sago. Before use, the starch must be carefully washed to leach out toxins contained in the pith. Extracting edible starch from the sago cycad requires special care due to the poisonous nature of cycads. Cycad sago is used for many of the same purposes as palm sago.
Cycad sago is extremely poisonous to animals and humans if ingested. All parts of the plant are toxic; however, the seeds contain the highest level of the toxin cycasin.
Where to see the Sago Cycad in Centennial Parklands
Kiosk, Banksia Way. Map Ref: J10