pronounced: ter-oh-KAW-lon spass-el-LAH-tum
Pterocaulon is derived from the Greek πτερον (pteron), a wing, and καυλος (kaulos), a stem, referring to the appearance of the leaves on the stem; spacelatum is also from the Greek, σφακελος (sphakelos), gangrene, mortification, a spasm, convulsion.
This plant is found only in Australia, relatively common throughout the tropical and subtropical parts of the country. It occurs in dry grasslands, and as a roadside weed. The plants photographed were growing near the pumping station at the end of the bitumen on the West Point road. It is a self-seeding biennial forb, with spherical flowerheads. It is a fast grower, and will grow either in full sun or in partial shade. It is aromatic, has an erect or straggling growth habit, 20 – 120 cm high, and is woolly to tomentose, with the hairs brownish. The plant is moderately frost tolerant.
The leaves are oblanceolate to oblong, obtuse or occasionally acute, 1 – 5 cm long, 0.3 – 1.5 cm wide, crenate or entire.
The compound flower heads are sessile or pedunculate, ovoid to globose, solitary, up to 2 cm long with much the same diameter. The outer bracts are spatulate, and the inner ones linear-lanceolate, whitish to pink in colour. The plant possesses only disk florets. The florets vary in colour from pink to purple. The achenes are nearly 1 cm long, and the pappus about 3 mm.
Apple Bush plays a very important part in indigenous medicine, and was soon adopted as a bushman’s remedy by early European settlers. Although these bushmen called the plant ‘horehound’ (taken from a European herb Marrubium vulgare), it is very likely that they derived their use of this plant from the Aboriginal peoples. They used a decoction of the leaves as a treatment for colds. Some flavoured their tea by putting a leaf or two in the billy as it came to the boil.
The Aborigines of central Australia use it in a variety of ways to treat colds:
• leaves may be inserted through a hole bored through the nasal septum;
• a bundle of leaves may be wrapped up and used as a pillow;
• crushed leaves may be mixed wth animal oil to make a massage ointment.
