Grevillea acropogon is a prostrate to erect shrub reaching a height of 1.5 to 2 metres by 1 or more metres wide. It can form a dense low shrub, acting as a groundcover.
It is another endemic species to the south-west of Western Australia and is only found in two locations; to the east and north of Tone-Perup Nature Reserve (east of Bridgetown).
It occurs in habitat such as Jarrah Forest, on sandy soils and open areas on the edges of such habitat.
It is a listed threatened species in the wild.
Leaves are alternate along the stems, light green, lobed with a sharp point on the end of each lobe; deeply divided (pinnatisect) with 5 to 7 linear lobes which are sharply-pointed; overall leaves to about 30 mm long and wide.
A grevillea inflorescence is technically a cluster of paired flowers, termed a conflorescence with the overall structure forming a raceme-like appearance. Grevillea species exhibit 3 main inflorescence structures:
1. A cylindrical to ovoid raceme (with flowers emerging around a 360° radius)
2. A single-sided raceme (with flowers produced on only one side, resembling a tooth-brush)
3. A condensed or clustered raceme (usually as long as it is wide, with species referred to as the spider-flowers).
Grevillea produce the inflorescences mostly at the terminals, beyond the foliage, which differs to the closely related Hakea.
In this species, flowers are more or less of the spider-variety, held in terminal racemes and are an eye-catching red; with racemes about 3 cm wide. Blooms are rich in nectar and are frequently visited by honeyeaters. Flowering extends through spring.
Individual flowers are composed of 1 carpel (female part) where the style and stigma protrude out; 4 stamens hidden away in the perianth; and the perianth (petals and sepals collectively) which connects to a pedicel. Proteaceae flowers do not have any discernible petals or sepals (having only one whorl) and so these are referred to as “tepals” of which there are 4. In this species, each flower about 20 mm long, with red carpels and red perianths.
The fruit is a follicle, about 1 cm long.
This attractive plant could be cultivated as a foreground plant in native garden beds. Our specimen has developed into a ground cover [in a garden near Armidale, NSW].
Our plant came from a nursery near Tenterfield, northern New South Wales. Introducing the species into cultivation and planting in the wild should ensure the survival of Grevillea acropogon, at least in gardens.
Best grown in an open sunny position on sandy soils with good drainage.
Propagation from cultivated plants should be from cuttings because Grevillea acropogon may have had relationships with other grevilleas in the garden. In this case, seed-grown plants may be hybrids.
The type specimen was collected in 1996 and formally published in 2000. The species is extremely rare and at one stage the wild population was reduced to 53 plants. In 2009 150 seedlings were introduced to a new site.
This species likely regenerates from seed after fire.
Grevillea is a diverse genus of about 365 species with about 357 occurring in Australia. Some species occur in New Caledonia, Indonesia and New Guinea. NSW currently has about 85 species although with a lot of subspecies and some informal taxa recognised.
Grevillea – was named in honour of Charles Francis Greville, (1749-1809) an 18th-century patron of botany and co-founder of the Royal Horticultural Society. He was also a British antiquarian, collector and politician who sat in the House of Commons from 1774 to 1790.
acropogon – Greek – akros (ἄκρος) meaning ‘high’ or ‘point’ as well as ‘sharp’ and –pogon (πώγων) meaning ‘beard’ or ‘hair’ – referring to the bearded ends of the flowers.
This species is listed as being threatened with extinction in the wild and is extremely rare with known populations in low numbers.
Western Australian Herbarium. Florabase: The Western Australian Flora – Grevillea acropogon profile page https://florabase.dbca.wa.gov.au/browse/profile/19444
Wikipedia – Grevillea acropogon profile page https://en.wikipedia.org/wiki/Grevillea_acropogon