Leaves alternate or opposite, scattered or crowded or clustered, lamina simple, margins entire or toothed; sessile or petiolate.
Heads axillary or terminal, sessile or pedunculate, solitary or in corymbose or paniculate conflorescences; heads broad-hemispherical to narrow-ovoid; involucral bracts imbricate in several series, herbaceous with scarious margins; receptacle pitted, the borders of the pits often finely toothed, lacking scales. Ray florets 1-seriate, female, ligulate or slender and filiform (rarely absent). Disc florets numerous or few, bisexual; corolla tubular. Anthers acute, obtuse or caudate basally. Style branches flattened with short, thick appendages above stigmatic lines.
Achenes striate, terete or slightly compressed, glabrous or variously hairy; pappus of numerous, usually unequal bristles.
| | Key to the species | |
| 1 | Growing on Lord Howe Island | 2 |
| Growing on mainland NSW | 3 |
| 2 | Leaves linear, 5–12 mm long, 0.5–1.5 mm wide | Olearia ballii |
| Leaves narrowly- to broadly-elliptic to obovate, 40–100 mm long, 1.5–3.5 mm wide
Back to 1 | Olearia mooneyi |
| 3 | Leaves sessile or subsessile | 4 |
| Leaves petiolate
Back to 1 | 38 |
| 4 | Leaves with margins flat | 5 |
| Leaves with margins weakly to strongly revolute
Back to 3 | 16 |
| 5 | Leaves with venation indistinct, apart from midvein | 6 |
| Leaves with venation distinctly reticulate or pinnate
Back to 4 | 14 |
| 6 | Leaves viscid on upper surface | 7 |
| Leaves not viscid on upper surface
Back to 5 | 10 |
| 7 | Leaves discolorous | Olearia viscidula |
| Leaves concolorous
Back to 6 | 8 |
| 8 | Leaves cuneate; apex truncate, 3-lobed | Olearia sp. Rhizomatica (I.R.Telford 11549) |
| Leaves linear or oblanceolate; apex acute or rounded
Back to 7 | 9 |
| 9 | Leaves linear; heads solitary or clustered; pappus 1- seriate | Olearia passerinoides |
| Leaves oblanceolate; heads in panicles; pappus 2- seriate
Back to 8 | Olearia decurrens |
| 10 | Leaves flat; heads solitary | 12 |
| Leaves conduplicate; heads in compound corymbs or leafy panicles
Back to 6 | 11 |
| 11 | Growing at high altitude in the southern tablelands of NSW | Olearia brevipedunculata |
| Growing in the western districts of NSW
Back to 10 | 13 |
| 12 | Disc florets ± 18; pappus 1-seriate, bristles ± 50 | Olearia muelleri |
| Disc florets ± 21; pappus 2-seriate, bristles ± 74
Back to 10 | Olearia calcarea |
| 13 | Leaves without a mucro; heads in compound corymbs; disc florets yellow | Olearia glandulosa |
| Leaves mucronate; heads in leafy panicles; disc florets pink
Back to 11 | Olearia suffruticosa |
| 14 | Leaves discolorous; ray florets ± 30; disc florets ± 20 | 15 |
| Leaves concolorous; ray florets ± 39; disc florets ± 86
Back to 5 | Olearia rudis |
| 15 | Ray florets 8–15; disc florets 7–16; pappus bristles ± 43 | Olearia canescens |
| Ray florets 16–30; disc florets 15–20; pappus bristles ± 44
Back to 14 | Olearia phlogopappa |
| 16 | Leaves with venation distinctly reticulate | Olearia rosmarinifolia |
| Leaves with venation indistinct, apart from midvein
Back to 4 | 17 |
| 17 | Leaves viscid on upper surface | Olearia iodochroa |
| Leaves not viscid on upper surface
Back to 16 | 18 |
| 18 | Leaves discolorous | 19 |
| Leaves concolorous
Back to 17 | 34 |
| 19 | Disc florets blue or mauve | Olearia ramosissima |
| Disc florets cream or yellow
Back to 18 | 20 |
| 20 | Heads axillary | 21 |
| Heads terminal
Back to 19 | 26 |
| 21 | Leaves grey-woolly or minutely tuberculate on upper surface | 22 |
| Leaves glabrous or subglabrous on upper surface
Back to 20 | 23 |
| 22 | Leaves grey-woolly, peduncles ± 3 mm long | Olearia axillaris |
| Leaves minutely tuberculate, peduncles ± 14 mm long
Back to 21 | Olearia ramulosa |
| 23 | Heads pedunculate; lamina linear or obovate | 24 |
| Heads sessile; lamina elliptic or narrow-obovate
Back to 21 | Olearia algida |
| 24 | Leaves usually only in the upper 1/2 of the shrub creating a crowded effect, 40–80 mm long | Olearia stenophylla |
| Leaves linear or obovate, 5–20 mm long
Back to 23 | Olearia subspicata |
| 25 | Leaves scattered, lamina linear or obovate, ± 5 mm long; heads pedunculate | Olearia subspicata |
| Leaves crowded, lamina elliptic or narrow-obovate ± 3 mm long; heads sessile
Back to | Olearia algida |
| 26 | Leaves tuberculate on upper surface | 27 |
| Leaves not tuberculate
Back to 20 | 29 |
| 27 | Heads ± 22 mm in diam.; disc florets blue or yellow | Olearia ramosissima |
| Heads ± 20 mm in diam.; disc florets yellow
Back to 26 | 28 |
| 28 | Leaves narrow- to broad-spathulate | Olearia microphylla |
| Leaves linear, narrow-elliptic or narrow-obovate
Back to 27 | Olearia ramulosa |
| 29 | Leaves stellate-hairy | Olearia asterotricha |
| Leaves not stellate-hairy
Back to 26 | 30 |
| 30 | Heads distinctly pedunculate | 31 |
| Heads sessile or subsessile
Back to 29 | 32 |
| 31 | Disc florets ± 10 | Olearia burgessii |
| Disc florets ± 14
Back to 30 | Olearia pimeleoides |
| 32 | Achenes not glandular | Olearia floribunda |
| Achenes glandular
Back to 30 | 33 |
| 33 | Leaves clustered, ± 0.8 mm wide | Olearia lepidophylla |
| Leaves scattered, ± 1 mm wide
Back to 32 | Olearia minor |
| 34 | Leaves narrow-elliptic to narrow-obovate or cuneate, glabrous to subglabrous or tomentose | 35 |
| Leaves linear, glandular or finely pubescent
Back to 18 | 36 |
| 35 | Leaves glabrous to subglabrous; achenes glabrous or subglabrous | Olearia magniflora |
| Leaves tomentose; achenes silky and glandular
Back to 34 | Olearia incana |
| 36 | Ray florets ± 18; disc florets ± 35 | 37 |
| Ray florets ± 30; disc florets ± 39
Back to 34 | Olearia flocktoniae |
| 37 | Disc florets ± 33; pappus with an outer row of short bristles | Olearia tenuifolia |
| Disc florets ± 33; pappus without an outer row of short bristles
Back to 36 | Olearia cordata |
| 38 | Leaves alternate | 39 |
| Leaves opposite
Back to 3 | 56 |
| 39 | Leaves viscid on upper surface | Olearia elliptica |
| Leaves not viscid on upper surface
Back to 38 | 40 |
| 40 | Pappus bristles pink | Olearia myrsinoides |
| Pappus bristles white or straw-coloured
Back to 39 | 41 |
| 41 | Leaves with venation reticulate or indistinct apart from midvein | 42 |
| Leaves with venation pinnate
Back to 40 | 52 |
| 42 | Heads axillary | Olearia quercifolia |
| Heads terminal
Back to 41 | 43 |
| 43 | Disc florets purple | Olearia montana |
| Disc florets cream or yellow
Back to 42 | 44 |
| 44 | Heads ± 40 mm in diam | Olearia stilwelliae |
| Heads ± 32 mm in diam
Back to 43 | 45 |
| 45 | Heads solitary or clustered | 46 |
| Heads in panicles or corymbs
Back to 44 | 47 |
| 46 | Ray florets ± 15; pappus 2-seriate | Olearia lasiophylla |
| Ray florets ± 16; pappus multiseriate
Back to 45 | Olearia phlogopappa |
| 47 | Heads in corymbs | 48 |
| Heads in panicles
Back to 45 | 51 |
| 48 | Heads sessile | Olearia oliganthema |
| Heads pedunculate
Back to 47 | 49 |
| 49 | Ray achenes minutely strigose; disc achenes densely glandular; pappus bristles 30–36 | Olearia heterocarpa |
| Ray and disc achenes glabrous; pappus bristles 26–80
Back to 48 | 50 |
| 50 | Leaves minutely silver-tomentose on lower surface; pappus bristles ± 44 | Olearia argophylla |
| Leaves beige-tomentose on lower surface; pappus bristles ± 50
Back to 49 | Olearia megalophylla |
| 51 | Disc florets cream to yellow; achenes silky; pappus with an outer row of short bristles | Olearia lirata |
| Disc florets yellow; achenes glabrous; pappus without an outer row of short bristles
Back to 47 | Olearia erubescens |
| 52 | Leaves grey-pubescent on upper surface | Olearia gravis |
| Leaves glabrous or subglabrous on upper surface
Back to 41 | 53 |
| 53 | Leaves silver-felted on lower surface; pappus without an outer row of short bristles | Olearia cydoniifolia |
| Leaves brown-, beige- or grey-felted on lower surface; pappus with an outer row of short bristles
Back to 52 | 54 |
| 54 | Leaves lanceolate, margins mostly entire but sometimes sinuate and serrate, peduncles <15 mm long | Olearia lirata |
| Leaves other than lanceolate, margins various, peduncles much greater than 15 mm long
Back to 53 | 55 |
| 55 | Leaves ovate, margins prickly or toothed, apex acute; peduncle ± 35 mm long | Olearia nernstii |
| Leaves elliptic, margins toothed or sinuately lobed, apex obtuse or rounded; peduncle ± 70 mm long
Back to 54 | Olearia tomentosa |
| 56 | Heads in panicles | Olearia chrysophylla |
| Heads in simple or compound corymbs
Back to 38 | 57 |
| 57 | Ray florets ± 4; disc florets ± 4 | 58 |
| Ray florets ± 6; disc florets ± 6
Back to 56 | 59 |
| 58 | Pappus bristles pink | Olearia aglossa |
| Pappus bristles white or straw-coloured
Back to 57 | Olearia covenyi |
| 59 | Leaves beige-tomentose on lower surface, margins flat, petiole ± 30 mm long | Olearia megalophylla |
| Leaves grey-tomentose on lower surface, margins revolute, petiole ± 12 mm long
Back to 57 | 60 |
| 60 | Leaves with margins entire; peduncles ± 25 mm long | Olearia alpicola |
| Leaves with margins toothed; peduncles ± 50 mm long
Back to 59 | Olearia oppositifolia |
