It is associated with wetland habitats, especially those in arid and semiarid regions subject to cycles of intermittent flooding and drying out.

[3] Lignum is a perennial, dioecious[4] shrub, growing to 2.5 m in height, with its multitude of thin, intertwined and tangled branches and branchlets forming dense thickets to the exclusion of other species.

The flowers are small and cream to yellowish, solitary or clustered along the branchlets and occurring through most of the year.

[6] Lignum often appears leafless as the leaves are produced on younger growth but soon die off, especially in dry conditions.

The plant's preferred habitats include floodplains, swamps, gilgais and other intermittently flooded areas.