pronounced: bur-SAH-ree-uh ten-yoo-ih-FOH-lee-uh
Bursaria is derived from the Latin bursa, a purse, referring to the shape of the fruits; tenuifolia is from tenuis, fine, thin, slim, slender, and folium, a leaf.
The Bursaria genus consists of large shrubs and small trees native to Australia. It was first described by Antonio José Cavanilles (1745–1804), a leading Spanish botanist, and one of the earliest Spanish users of Linnaeus’s classification method. He was director of the Royal Botanical Garden and Professor of Botany in Madrid for the last four years of his life. He named at least 100 genera of plants, mainly from Oceania, and half of these genera still bear the names he gave them. In botanical records, his standard author abbreviation is Cav. He did not himself visit Australia: his descriptions of Australian plants were based on collections made near Port Jackson and Botany Bay by Luis Née, who visited the area in 1793 as botanist on the Alejandro Malaspina expedition. Malaspina was an Italian nobleman who spent most of his life as a Spanish naval officer. He circumnavigated the world in 1786–1788, and then, in 1789–1794, led a scientific expedition throughout the Pacific Ocean, exploring and mapping much of the west coast of the Americas from Cape Horn to the Gulf of Alaska, crossing to Guam and the Philippines, and stopping in New Zealand, Australia and Tonga.
Bursaria tenuifolia is a tall shrub to small tree, 3 – 9 m tall. It is native to north-eastern Queensland, found usually along stream banks and in open scrub land, and very often associated with seasonal watercourses. As far as I know, this species is not native to Magnetic Island, but has been introduced as a garden species. The bark of the tree is smooth, and creamy grey in colour. There are spines on the stems of young growth, but these disappear with maturity. The leaves are lanceolate, tapering to the base, and with a rounded tip. They are shiny green above, dull beneath, lacking the hairs of many other Bursaria species, thin-textured, 3 – 5 cm long by 1 – 1.5 cm wide. The white flowers are borne in large erect panicles, and are followed by small, heart-shaped, flattened, 2-valved, brown capsules a little under 1 cm in length.
Bursaria tenuifolia may be propagated either from seed or from cuttings, and does well in a garden, probably best in dappled shade. It forms am attractive shrub that is spectacular when in flower, and attracts many types of insect. It is a food plant for the Twig Looper Ectropis excursaria.
The glycoside Aesculin was the active ingredient for a sun-screening lotion much used in the Second World War, especially for the fully-exposed turret gunners in Allied bombers during their raids over Europe. It was originally obtained in low concentrations from the bark of the English Horse Chestnut trees, Aesculus hippocastanum, following the felling of the trees. This destructive process was curtailed when it was found to occur in dried Bursaria leaves, after hammer milling and solvent extraction. It was also used as a valuable bacteriological reagent in the testing for tropical diseases for Australian forces serving in the tropics, and again was used for effective treatment of blood disorders in Australian servicemen fighting in jungle conditions.
