Stenocarpus sinuatus (Firewheel Tree) - This upright growing evergreen tree reaches to 100 feet tall in its native rainforest habitat but is usually seen as a small to medium sized tree to 25-30 feet tall by 15 feet wide in cultivation in California. It has gray bark with young brown branches and is notable in or out of flower for its very attractive large (6 to 15 inch long) dark green leathery leaves that have wavy margins and are pinnately lobed when young plants. The 1 to 1 1/2-inch-long flowers, primarily red or reddish orange with a yellow globular tip, are arranged with 6 to 20 flowers in an umbel that is reminiscent of a red wagon wheel - these 3 inch wide wheels are quite striking and can appear any time of the year but primarily in fall and winter here in Southern California. The flowers are not on terminal branches but come from below a leaf petiole so would be partly hidden if not for their vibrant color, combined size and unique shape.
Plant in full sun to light shade and give it occasional deep watering. Despite its more tropical origins, this plant has proven adaptable to a range of climates, tolerating temperatures down to around 25° F and drier mediterranean climates with the addition of some supplemental irrigation. It also is tolerant of most soils so long and they are fairly well-drained but avoid applications of Phosphorus fertilizers and in some cases this plant may benefit from supplemental micronutrient applications. It was noted by onetime Santa Barbara City Arborist Dave Gress that this plant disliked being planted in close proximity of streetlamps, however it can be grown in a sunny or partly shaded locations.
This plant's natural distribution is within subtropical to tropical rainforests in Australia from New South Wales in the south to the Atherton Tableland in Queensland in the north. It also occurs in Papua New Guinea. The name Stenocarpus was first used in 1810 to describe Stenocarpus salignus by the Scottish botanist Robert Brown (1773-1858) and comes from the Greek word 'stenos' meaning "narrow" and 'karpos' meaning "fruit" in reference to the shape of the seed capsules (follicles) which are flattened and narrowed. The specific epithet is from the Latin word 'sinuatus' which means "wavy" in reference to the undulating margins of the leaves. This plant, first named Agnostus sinuata in 1832 by the Scottish botanist John Claudius Loudon (1783 - 1843) has also been known as Cybele sinuata before Austrian botanist Stephan Ladislaus Endlicher, who was the director of the Botanical Garden of Vienna, reclassified it in 1848 to its current name. Other common names include Queensland Firewheel, Wheel of Fire, White Beefwood, Tulip Flower, White Oak, White Silky Oak and Rotary Tree. This latter name reportedly has led to the adoption of the plant as a mascot by Rotary Clubs around the world. The Firewheel Tree was introduced into California by Stephen Nolan at his Belleview Nursery in Oakland in 1871 and we have grown it at San Marcos Growers since 1979. There are many nice street trees of this species throughout Santa Barbara.
The information about Stenocarpus sinuatus displayed on this web page is based on our research conducted in the nursery's horticultural library and from reliable online resources. We also include observations made about it as it grows in our nursery gardens and other gardens we have visited, as well how the crops have performed in containers in our nursery field. We will also incorporate comments we receive from others and welcome hearing from anyone with additional information, particularly if they can share cultural information that would aid others in growing this plant. |