pronounced: bur-SAH-ree-uh in-KAR-nuh
Bursaria is derived from the Latin bursa, a purse, referring to purse-like seed capsules; incana is from the Latin incanus, grey or hoary, referring to the underside of the leaves.
This close relative of Bursaria tenuifolia is a native of north-eastern Australia, north of a line stretching roughly from just below Arnhem Land in the Northern territory to the east coast on the Queensland/NSW border.
Bursaria incana is a tall shrub or small, sparse tree 3 – 7 m tall, commonly found in dry woodland. Young branches are covered with soft white hairs, and young plants carry spines on the stem until they are 1 – 2 m tall. The bark is grey and rough.
The leaves are oblong, blunt, somewhat pendant, coloured green above, and whitish and hairy beneath, 5 – 8 cm long and 1 – 3 cm broad.
The 5-petalled flowers are creamy white and sweetly scented, about 1.2 cm in diameter and borne in large dense terminal panicles. The usual flowering season is between February and April.
After the flowering, 2-valved flattened purse-shaped capsules up to 1 cm by 1 cm are produced, containing flat brown seeds.
The species likes full sun and well-drained soil. In the wild it tends to become a sparse small tree, but judicious pruning and watering will result in an attractive plant. The flowers were photographed on a tree planted just inside the link fence around the Ergon yard in Picnic Bay, on the Birt Street side.
Propagation is from seed, which germinates readily, or from cuttings.
Although the timber from this little tree is only small, it turns, machines, sands and finishes beautifully. It doesn’t have obvious growth rings like real pine, which makes it much nicer to work. If the wood is air dried in log form, it will often split to the heart in at least one place. It is probably best to turn it while green – or at least to rough out the articles while green, allow them to dry for a couple of months, and then finish them off.
In parts of the Northern Territory and western Queensland, Bursaria plants play an important part in the regeneration of pastures in bush runs. Sheep and cattle grazing in degraded woodland communities cause the demise of many native shrubs, herbs, grasses and ground covers. Depending on the stocking rates and how long the grazing continues unabated, the ecological values of the woodland community may diminish rapidly. At the stage just prior to when natural regeneration loses its ability to heal the land, the degradation signs are typically browsed Bursaria shrubs standing solitary among a plethora of introduced pasture weeds and erosion scars. If the situation is caught in time, the stock removed and the area fenced, the remnant Bursaria not only provide critical habitat for the recolonization by insects and birds, but also provide a protective framework for young native seedlings to germinate and grow from the native seed stored in the soil. Each Bursaria bush offers a nectar and larval food source for birds, beetles, moths, wasps, bees, ants, etc. This in turn allows pollination, seed dispersal and nutrient cycling processes to be initiated. These are the building blocks for successful natural regeneration of degraded woodland communities.
This is a food plant for the Twig Looper Ectropis excursaria, and the Dull Copper Paralucia pyrodiscus.