Introduced, warm-season, perennial, erect herb to 1 m tall. It has a woody base and deep taproot. Leaves are darker above and lanceolate, diamond shaped or oblong, with toothed edges. Flowers are yellow to pale orange, 1-1.5 cm wide and solitary on slender stems 1-3 cm long. Flowering is from late spring to autumn. A native of tropical regions, it is a weed of disturbed and shaded areas, such as gardens, overgrazed pastures and wasteland. Favoured by heavy grazing, shade or disturbances which reduces plant competition and ground cover. Common in horse paddocks. Has low palatability for cattle and low feed value. Control can be achieved by increasing the density and bulk of pastures through improved fertility and the use of good grazing management. Grazing with goats is also effective, as it is highly palatable to them. Isolated plants can be chipped out, but will regrow if taproot is not removed. Slashing at early flowering will reduce seed  production and produce new growth for spraying. Spot spray young plants with selective or nonselective herbicides, although mature plants are quite resistant to herbicides.
<a rel="nofollow" class="external text" href="https://www.flickr.com/people/73840284@N04">Harry Rose</a> from South West Rocks, Australia
CC BY 2.0
<a rel="nofollow" class="external text" href="https://www.flickr.com/photos/macleaygrassman/15521071794/">Sida rhombifolia leaf1</a>