Callitris pyramidalis, known variously as the Swamp Cypress, Swan River Cypress and King George's Cypress, is a tall shrub or small tree said to reach a height of eight metres. In our cold climate garden specimens reach about four metres after five years in the ground. They would probably attain a greater height with more watering. The typical Callitris foliage is dark green. The male cones are small, 3–6 mm long, and are found on the ends of the twigs. The female cones are globular to ovoid, 15 mm in diameter. Female cones are both profuse and conspicuous.
In common with other Callitris the cones, of this species, are held on the plant for many years. They only open if a branch or the tree dies. Because of the number of cones large numbers of seeds are released in the event of damage or death of the plant. As an example: A solitary C. pyramidalis, on a Western Australian island, was killed by fire. Subsequently hundreds of seedlings germinated. Up to 150 seedlings were counted per square meter ten metres from the deceased plant.
The species was collected, from Perth, in 1841 by Johann Preiss and named Actinostrobus pyramidalis. In 2010 the species was renamed Callitris pyramidalis.
The Swamp Cypress is endemic to the southwest corner of Western Australia.
The thumbnail is a watercolour painting, of a stem, by Robert Fitzgerald in the 1870’s.
Propagate from seed.
Warren and Gloria Sheather