Casuarina glauca or Swamp She-oak was the tree-du-jour when the Park was being established, and they were widely planted across the precincts. While the trees offer some benefit such as shade and screening of natural areas from traffic or pedestrian disturbance, they offer limited ecological value, as the mat of casuarina needles under established trees severely inhibit the germination and growth of understory plants. In Narawang Wetland, the trees also cause excess shading of habitat ponds of the Green and Golden Bell Frog, which prefer sunny ponds.
To improve bell frog habitat, a grove of Swamp She-oak overshading pond N9 (below) was cut down, and the trunks reduced to approximately 1m length. These were arranged in small piles of two to three logs around the wetland, to provide extra habitat for ground-dwelling fauna such as lizards, frogs, as well as invertebrates. The cleared area will be planted with shrubs to provide habitat for small bush birds.