What Does It Look Like?
What is it?
European Olive (Olea europaea subsp. europaea) is a much branched evergreen shrub or tree, 2–10 (rarely 15) m high, without prickles or spines. The leaves grow in pairs along the branches. They are narrowly linear-oblong to linear-oval, 3–7 cm long and 0.8–1 cm wide, dark grey-green above, and silvery to white below due to covering of short hairs. The edges of the leaf curl back, the leaf-base narrows gradually to wedge-shaped, the leaf-tip is pointed, and the main venation (mid-rib) obvious on upper surface with some lateral veins just visible. The leaf stalks are up to 10 mm long.
Flowers are cream or white in colour borne in many-flowered clusters on branches 5–6 cm long, which arise from the base of the leaf stalks. Each flower is small, with four petals, 4–5 mm long with a tube 1–2 mm long, with lobes c. 3 mm long that are re-flexed back at maturity. Flowers have 2 male stamens, with a single female two lobed stigma. Flowers are surrounded by a calyx (green buds) of 4 triangular sepals each about 1–2 mm long.
The fruits are ellipsoidal to almost globular, smooth, purple-black when mature, 1.5–2.5 cm long, with an edible flesh surrounding a single stone or seed which is brown to black (Green 1986; Jeanes 1999; Green 2002).
There are many named cultivars of olive, including ‘Barnea’, ‘Kalamata’ and ‘Manzanilla’, (Government of South Australia 2021)
For further information or assistance with the identification of European Olive, contact the herbarium in your state or territory.
Growth form (weed type/habit)
Where it currently grows? Preferred habitat
European Olive grows in areas receiving at least 500 mm rainfall per year, with cool winters and hot, relatively dry summers. It thrives in natural and modified habitats with moderate levels of soil nutrients and grow in a wide range of soils from deep loams to rocky outcrops. It has become naturalised along roadsides, and in bushland, waste areas and disturbed sites (Parsons & Cuthbertson 1992). European Olive is well-adapted to cool wet winters and warm dry summers, and very tolerant of drought.
Are there similar species?
European Olive is of very similar appearance to African Olive (Olea europaea subsp. cuspidata).
African Olive normally has larger leaves; from 6–10 cm long, and wider leaves 1–2.5 cm wide, with the lower surface green or yellowish brown.
European Olive normally has smaller leaves; from 3–7 cm long, and thiner leaves 0.8–1 cm wide, with the lower surface whitish or silvery.
Olives can also be confused with some native species, including Australian Olive (O. paniculata), which has relatively small fruits (about 10 mm long, compared to 15-30 mm for European Olive) occurring on the east coast from Newcastle in New South Wales to far north Queensland past Cairns and Port Douglas to Lockhart.
The Mock Olives (Notelaea spp) also have relatively small fruits, and Boonaree (Alectryon oleifolius) has alternately arranged divided leaves and dry fruits (Navie 2004).