Eucalyptus botryoides, commonly known as the bangalay, bastard jarrah, woollybutt[2] or southern mahogany, is a small to tall tree native to southeastern Australia.

[7] The thick, fibrous, rough and flaky bark covers the trunk and larger branches, and is vertically furrowed.

[4] Developing from small cylindrical or club-shaped (clavate) buds,[8] the white flowers appear from January to April,[10] and are arranged in groups of six to eleven in umbellasters.

[3] It has been classified in the subgenus Symphyomyrtus, Section Latoangulatae, Series Annulares (red mahoganies) by Brooker and Kleinig.

[5] Eucalyptus botryoides is only found in lowlands, from sea level to 300 m (980 ft) altitude, and in areas of rainfall from 700 to 1,300 mm (28 to 51 in).

[3] Trees in mixed open forest it grows with include turpentine (Syncarpia glomulifera), spotted gum (Corymbia maculata), red bloodwood (C. gummifera), blackbutt (E. pilularis), Sydney blue gum, red mahogany (E. resinifera),[3] and smooth-barked apple (Angophora costata).

[10] Associated understory plants in wetter forests with some rainforest transition include lillypilly (Syzygium smithii) and wattles.

[5] It is a component tree of wetland forest in Booderee National Park alongside blackbutt, red bloodwood, grey ironbark (Eucalyptus paniculata), scribbly gum (E. sclerophylla), old man banksia (Banksia serrata), coast banksia (B. integrifolia) and snow-in-summer (Melaleuca linariifolia), with understory plants such as jointed twig-rush (Baumea articulata), tall spike-rush (Eleocharis sphacelata), prickly tea-tree (Leptospermum juniperinum), and zig-zag bog-rush (Schoenus brevifolius).