Eucalyptus extrica is a spreading mallee that typically grows to a height of and forms a
lignotuber. It has smooth light grey over brown bark, sometimes with rough, fibrous or ribbony bark on the lower stems. Young plants and
coppice regrowth have slightly
glaucous, elliptical to egg-shaped leaves arranged in opposite pairs. Adult leaves are also arranged in opposite pairs, lance-shaped to egg-shaped, the same dull green on both sides, long and wide on a
petiole long. The flower buds are arrange in leaf
axils in groups of three on a flattened
peduncle long, the individual buds on
pedicels long. Mature buds are oval, long and wide with a rounded to flattened
operculum. Flowering occurs between January and April and the flowers are whitish. The fruit is a woody, cylindrical to barrel-shaped
capsule long and wide with the valves near to rim level. Tallerack (
E. pleurocarpa) has a similar habit but has noticeably shorter, wider, glaucous leaves, glaucous buds and fruit. Intergrades between the two species have been recorded. ==Taxonomy and naming==