Shrub or tree 1–15 m. Branchlets glabrous, glaucous. Leaves reduced to phyllodes; phyllodes obovate to narrowly oblanceolate, narrowed and often recurved at the base, 5–17 × 1.5–5 cm, glabrous, greyish green to glaucous, penninerved. Inflorescence axillary, racemose to paniculate, main axes 2–10 cm long; heads globular, with 20–35 flowers, bright golden- or lemon-yellow. Flowers densely packed, 5-merous. Legume oblong, flat, slightly raised over seeds, 4–15 × 1.2–2.5 cm, papery to thinly leathery, slightly glaucous. Seeds shiny black, with aril. Flowering in spring. Chapman et al. 2001a, 2001b. Distribution AUSTRALIA: Australian Capital Territory, New South Wales, Victoria. Habitat Montane forest and woodland between 500 and 1700 m asl. USDA Hardiness Zone 7–8. Conservation status Not evaluated. Illustration Ross & Irons 1997.
Acacia obliquinervia is one of the most attractive of phyllodic wattles, forming a neatly shaped tree that is densely clad in broad phyllodes. These are often greyish green but some trees are an excellent glaucous-blue. Leaves on young shoots are reddish at first. The bright yellow flowers appear in spring and contrast well with the foliage. Though not yet well known in cultivation, A. obliqui nervia is one of the most hardy of the genus. In the wild it has been known to survive –16 ºC and in cultivation it seems to be able to cope with similar temperatures, though young trees have been cut to the ground by –13.5 ºC in Germany (Ross & Irons 1997). It is in cultivation throughout Europe and in North America wherever climatic conditions are appropriate, and is rated by enthusiasts as a superb new species to try (S. Hogan, pers. comm. 2007), but every effort should be made to obtain or select the best glaucous forms from batches of seedlings. Germination is sporadic after the standard boiling water treatment, and a cold stratification period may be necessary to achieve good germination rates (Ross & Irons 1997). It is very sensitive to over-watering (Wrigley & Fagg 1996).