sticky senna

Senna glutinosa is a more or less glabrous, erect or straggling shrub or small tree, that typically grows to a height of 0.3–4 m (1 ft 0 in – 13 ft 1 in), its stems, leaves and outer flower parts sticky. The leaves are pinnate with up to seven pairs of leaflets spaced more than 6 mm (0.24 in) apart, on a petiole more than 6 mm (0.24 in) long, the size and shaped of the leaflets varying with subspecies. The flowers are yellow and arranged in groups near the ends of branches, the sepals oval, 8–10 mm (0.31–0.39 in) long and greenish-yellow. The petals are oval, 11–15 mm (0.43–0.59 in) long and there are ten fertile stamens in each flower, the anthers 4–5 mm (0.16–0.20 in) long. The fruit is a flat pod 50–70 mm (2.0–2.8 in) long and 10–20 mm (0.39–0.79 in) wide.

Senna glutinosa grows in arid shrubland in all mainland states of Australia and the Northern Territory, but not in Victoria. Subspecies chatelainiana in the central west of Western Australia, and subsp. glutinosa from the north-west of Western Australia to the Northern Territory and north-western South Australia. Subspecies × luerssenii occurs from the central coast of Western Australia to near the Northern Territory border, and subsp. pruinosa is found from north-western Western Australia to far northern South Australia, and far western Queensland and New South Wales.