About Helicia glabriflora F.Muell.
Nomenclature and General Growth Form
Helicia glabriflora, formally named Helicia glabriflora F.Muell., is a species of rainforest shrub or small tree found in eastern Australia. Its common names are smooth helicia, pale helicia, pale oak, leather oak, and brown oak.
Distribution Range
This species grows naturally across a variety of rainforest types, ranging from the Illawarra region of New South Wales at 34° S north to the Townsville area of Queensland at 19° S. Out of roughly 100 total Helicia species across the globe, this species grows naturally further south than any other.
Habitat Substrate Preference
In the Minnamurra Rainforest and Robertson area of Illawarra, New South Wales, H. glabriflora is more commonly found on relatively fertile basalt and alluvial soils.
Size and Stem Dimensions
Mature plants reach up to 15 m (50 ft) in height, with a maximum stem diameter of 30 cm (12 in). Their grey or brown trunk is generally smooth, marked by small bumps and horizontal lines.
Leaf Characteristics
They produce leathery-textured leaves that measure 5 to 15 cm (2 to 6 in) long and 1.5 to 4 cm (0.6 to 1.6 in) wide. Leaf stems are 1 to 3 mm long, swollen at the base, and are often reduced to a pulvinus.
Flowering and Inflorescence
Yellow or white flowers bloom between April and September, arranged in bottle-brush-shaped compound inflorescences.
Fruit and Seed Traits
The fruit is a purple-blue drupe around 16 mm (0.63 in) long, which matures between April and November and contains a single green seed.
Family Diagnostic Features
The flowers and fruit of Helicia glabriflora display the characteristic appearance of the plant family Proteaceae.
Germination Pattern
Seeds of this species germinate slowly, typically completing germination after three months with a 90% success rate.
