A slender, small tree, sometimes dense and rounded but generally with a light canopy. The light green phyllodes; flattened leaf-like stems which replace the true leaves as the main photosynthetic structure, are narrow and sickle-shaped (this species is frequently misidentified as a Eucalyptus because of this feature). Of the other indigenous wattles around Melbourne it is easily confused with Blackwood, Acacia melanoxylon. The Lightwood, is similar in almost all respects except that the phyllodes are usually darker and not sickle-shaped. A reliable distinction between the two is that Blackwood flowers in early spring whereas Lightwood flowers in December-February. Both species produce clumps of twisted pods but in the Blackwood these are produced in the months immediately after flowering, releasing the seeds, each half-wrapped in a long, twisted orange ribbon-like stalk (the 'aril'). In Lightwood, the fertilised flowers go into a curious state of suspended development, only maturing the following season to release the seeds in about December, just ahead of flowering. The pods of lightwood are extravagantly twisted and the shiny black seeds lack the colourful stalk (aril) of the Blackwood seeds.