Eucalyptus forresterae is a shrubby, whipstick mallee that typically grows to a height of and has smooth light grey to whitish bark that is shed in strips or sheets. Young plants and
coppice regrowth have crowded leaves arranged in opposite pairs, egg-shaped to heart-shaped or round, a lighter shade of green on the lower side, long and wide. Adult leaves are arranged alternately, the same glossy green on both sides, lance-shaped to narrow egg-shaped, long and wide on a
petiole long. The flower buds are arranged in leaf
axils in groups of between eleven and twenty one on an unbranched
peduncle long, the individual buds
sessile. Mature buds are spindle-shaped, long and about wide with a horn-shaped
operculum about the same length as the
floral cup. Flowering occurs in summer and the flowers are white. The fruit is a sessile, woody, cup-shaped to shortened hemispherical
capsule about long and wide with the valves below the rim of the fruit. ==Taxonomy and naming==