About Jacksonia sternbergiana Hügel
Jacksonia sternbergiana is an erect or weeping shrub or small tree, which typically reaches 1.5–5 m (4 ft 11 in – 16 ft 5 in) in height and 1–3 m (3 ft 3 in – 9 ft 10 in) in width. It has dull green branches; its terminal branches are 4–92 mm (0.16–3.62 in) long, 1–2 mm (0.039–0.079 in) wide, and sharply pointed. The leaves of this species are reduced to broadly egg-shaped, pale brown scales that measure 1.0–3.3 mm (0.039–0.130 in) long and 0.7–2.2 mm (0.028–0.087 in) wide. Its flowers are scattered along the branches, each growing from a 5.5–8.3 mm (0.22–0.33 in) long pedicel. Lance-shaped bracteoles 0.6–1.2 mm (0.024–0.047 in) long are attached to the middle of each pedicel. The floral tube is 1.3–1.4 mm (0.051–0.055 in) long. The sepals are membranous, with lobes that are 7.3–9.7 mm (0.29–0.38 in) long and 1.3–2.3 mm (0.051–0.091 in) wide. The flowers are yellow-orange with red markings. The standard petal is 8.9–10 mm (0.35–0.39 in) long, the wing petals are 7.7–10 mm (0.30–0.39 in) long, and the keel petal is 7.2–9 mm (0.28–0.35 in) long. The stamens have white filaments with red ends, and the filaments measure 6–11.7 mm (0.24–0.46 in) long. Flowering occurs year-round, and the fruit is a woody, hairy pod that is 10–15.5 mm (0.39–0.61 in) long and 4.5–6.0 mm (0.18–0.24 in) wide. This species of Jacksonia is widespread between Northampton and Green Range, within the Avon Wheatbelt, Geraldton Sandplains, Jarrah Forest, Mallee and Swan Coastal Plain bioregions of south-western Western Australia. This plant serves as food for the larvae of several butterfly species, including the turquoise jewel, fringed heath-blue, and long-tailed pea-blue.
