Casuarina cristata, commonly known as belah or muurrgu,[2] is a species of flowering plant in the family Casuarinaceae and is endemic to inland eastern Australia.

[2][3][4][5] Casuarina cristata was first formally described in 1848 by Dutch botanist Friedrich Anton Wilhelm Miquel in his book Revisio critica Casuarinarum from specimens collected by Allan Cunningham near the Lachlan River.

[2] Other common names include scaly-barked casuarina, scrub she-oak, billa, ngaree, bulloak and swamp oak.

Here it is found as a dominant tree with brigalow (Acacia harpophylla), black gidyea (A. argyrodendron), bimble box (Eucalyptus populnea), Dawson River blackbutt (E. cambageana), E. pilligaensis and the smaller trees such as wilga (Geijera parviflora) and false sandalwood (Eremophila mitchellii) in open forest over mainly Cenozoic clay plains.

[7] Other plants it grows with include boonaree (Alectryon oleifolius), sugarwood (Myoporum platycarpum) and nelia (Acacia loderi).