The smooth branches are sometimes armed with thorns, and the leaves are arranged alternately along the stems or clustered around the nodes and have a pine-like fragrance when bruised.

[2][3][4][5][6] First collected by Europeans in the vicinity of Port Jackson, Bursaria spinosa was first formally described by Antonio José Cavanilles in 1797 in his book, Icones et Descriptiones Plantarum.

[8] Summer flowering has given rise to the name (Tasmanian) Christmas bush in Tasmania and South Australia (not to be confused with Prostanthera lasianthos).

For example, in 1893, Jules Alexandre Daveau, in Désiré Georges Jean Marie Bois's Dictionnaire d'Horticulture, described varieties inermis[10] (meaning 'without spines') and macrophylla[11] ('large leaves'),[12] but var.

[18][3] In New South Wales, B. spinosa grows in dry to wet forest in all but the most arid parts of the state, and is sometimes a weed on cleared land.

[4] In the Sydney region, it grows on clay- and shale-based soils, as an understory plant in association with grey box (Eucalyptus moluccana) and forest red gum (E. tereticornis) as well as the grass Themeda australis.

[19] A wide variety of insects visit the flowers of Bursaria spinosa, the most important pollinators of which appear to be beetles of several families.

Caterpillars which feed on Bursaria spinosa include Proselena annosana, two-ribbed arctiid (Palaeosia bicosta) and bark looper moth (Ectropis subtinctaria), while those of the clouded footman (Anestia ombrophanes) graze on algae and lichens which grow on the branches.

[19] The bright copper (Paralucia aurifera) and ant species Anonychomyrma nitidiceps form a complex symbiotic relationship on Bursaria spinosa.