Banksia seminuda, commonly known as the River Banksia, is a tree

Tree

A tree is a perennial woody plant. It is most often defined as a woody plant that has many secondary branches supported clear of the ground on a single main stem or trunk with clear apical dominance. A minimum height specification at maturity is cited by some authors, varying from 3 m to...

 in the plant

Plant

Plants are living organisms belonging to the kingdom Plantae. Precise definitions of the kingdom vary, but as the term is used here, plants include familiar organisms such as trees, flowers, herbs, bushes, grasses, vines, ferns, mosses, and green algae. The group is also called green plants or...

 genus

Genus

In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...

 Banksia

Banksia

Banksia is a genus of around 170 species in the plant family Proteaceae. These Australian wildflowers and popular garden plants are easily recognised by their characteristic flower spikes and fruiting "cones" and heads. When it comes to size, banksias range from prostrate woody shrubs to trees up...

. It is found in south west Western Australia

Western Australia

Western Australia is a state of Australia, occupying the entire western third of the Australian continent. It is bounded by the Indian Ocean to the north and west, the Great Australian Bight and Indian Ocean to the south, the Northern Territory to the north-east and South Australia to the south-east...

 from Dwellingup

Dwellingup, Western Australia

Dwellingup is a town in Western Australia, located in a timber and fruitgrowing area in the Darling Range east-south-east of Pinjarra. At the 2006 census, Dwellingup had a population of 346.-Name:...

 (32°42′S) to the Broke Inlet east of Denmark

Denmark, Western Australia

Denmark is a town in the Great Southern region of Western Australia, south-south-east of the state capital of Perth. At the 2006 census, Denmark had a population of 2,732.-History:...

 (34°57′S). It is often mistaken for and was originally considered a subspecies

Subspecies

Subspecies in biological classification, is either a taxonomic rank subordinate to species, ora taxonomic unit in that rank . A subspecies cannot be recognized in isolation: a species will either be recognized as having no subspecies at all or two or more, never just one...

 of the Banksia littoralis

Banksia littoralis

Banksia littoralis, commonly known as the Swamp Banksia, Swamp Oak, Pungura and the Western Swamp Banksia, is a tree in the plant genus Banksia. It is found in south west Western Australia from the south eastern metropolitan area of Perth to the Stirling Range and Albany...

(Swamp Banksia). One of the tallest Banksia species the River Banksia has a shrub subspecies remanens.

Description

The River Banksia grows up to 20 metres (65 ft) tall with a usually brown to grey trunk covered with a hard grey fissured bark. The tree trunks are often straight and tall as the species grows in sheltered forest areas.

Flowering occurs between late summer and late winter. The yellow (occasionally red) flower spikes grow up to 200 mm (8 in) long by 70 mm (3 in) wide, the fruiting cones can remain on the trees for many years after shedding the flowers early. Its leathery leaves are between 70 mm (3 in) and 120 mm (5 in) long with fine teeth, subspecies remanens leaves have few if any teeth except at the tips of the leaves.

Distribution and habitat

This tree is found on the fringes of the rivers and creeks in Jarrah, Marri

Corymbia calophylla

Corymbia calophylla is a bloodwood native to Western Australia. Common names include Marri and Port Gregory Gum, and a long standing usage has been Red Gum due to the red gum effusions often found on trunks.It is distinctive among bloodwoods for its very large buds and fruit Corymbia calophylla...

 and Karri forests, between Dwellingup and Denmark. Stephen Hopper

Stephen Hopper

Stephen Donald Hopper is a Western Australian botanist, specialising in conservation biology and vascular plants. He has written eight books, and has over 200 publications to his name. He was Director of Kings Park in Perth for seven years, and CEO of the Botanic Gardens and Parks Authority for five...

 described the subspecies remanens as a short leaved shrubby form found in the coastal sands below granite outcrops in the Walpole-Nornalup National Park

Walpole-Nornalup National Park

Walpole-Nornalup National Park is a national park in the South West region of Western Australia , 355 km south of Perth. It is famous for its towering Karri and Tingle trees. Red Tingle trees are unique to the Walpole area.-Tourism:...

, however George

Alex George

Alexander Segger George is a Western Australian botanist. He is the authority on the plant genera Banksia and Dryandra...

 does not feel this form warrants taxonomic recognition as it lies within the normal variability of the species and there was no clear distinction between it and the other populations of B. seminuda.

Taxonomy

B. seminuda lies within the series Spicigerae and is clearly very closely related to B. littoralis.

Ecology

An assessment of the potential impact of climate change

Climate change

Climate change is a significant and lasting change in the statistical distribution of weather patterns over periods ranging from decades to millions of years. It may be a change in average weather conditions or the distribution of events around that average...

on this species found that its range is likely to contract by between 30% and 80% by 2080, depending on the severity of the change.

Cultivation

B. seminuda is a vigorous and adaptable plant. There are reports of seedlings coming up near cultivated plants in Victoria which suggests caution should be advised if planting near bushland.