Flora of Australia Online
Grevillea pteridifolia Knight, Cult. Prot. 121 (1809)
T: Endeavour's River & Point Lookout [Qld], 1770, J.B. & D.S. [J.Banks & D.Solander ]; lecto: BM, fide D.J.McGillivray, Taxon 34: 536 (1985); isolecto: NSW.
Grevillea chrysodendron R.Br., Trans. Linn. Soc. London 10: 176 (1810), as Grevillea Chrysodendrum ; Grevillea pteridifolia var. typica Domin, Biblioth. Bot. 89: 33 (1921), nom. illeg. T: 'In Novae Hollandiae ora septentrionali; Carpentaria; prope littora' [protologue]; lecto: Carpentaria. Islands g. g2. h. Arnhem. South Bay [N.T., c. 18 Dec. 1802], R.Brown ; lecto: BM, fide D.J.McGillivray & R.O.Makinson, Grevillea 436 (1993).
Grevillea mitchellii Hook., in T.L.Mitchell, J. Exped. Trop. Australia 265 (1848); Grevillea pteridifolia var. mitchellii (Hook.) Domin, Biblioth. Bot. 89: 587 (1921); lecto: Sub-Tropical New Holland [Qld?], [later annot. 'June 1846', probably in error, protologue indicates 7 Aug. 1846], [T. ] Mitchell 166 ; lecto: K, fide D.J.McGillivray & R.O.Makinson, Grevillea 436 (1993).
Illustrations: J.Brock, Top End Native Pl. 206 (1988); J.W.Wrigley & M.Fagg, Banksias, Waratahs & Grevilleas 280 (1989); P.M.Olde & N.R.Marriott, Grevillea Book 1: 21, fig. 12 (1994); 2: 114 (bottom right), 115 (88A, B), 116 (88C–E) (1995).
Regeneration variable, usually mainly from seeds, sometimes also lignotubers, occasionally also rhizomes and epicormic shoots.
Shrub or tree 2–14 m high, or rarely a prostrate shrub. Leaves 10–45 cm long, usually pinnatisect (rarely a few leaves bisect or entire and linear) with (3–) 13–29 ascending primary lobes, occasionally the lower several pairs again 2–5-sect; ultimate lobes linear or very narrowly ovate, (5–) 15–25 cm long, 1–4 (–10) mm wide, not pungent; margins shortly refracted to angularly revolute; lower surface usually partly exposed, subsericeous with straight hairs. Unit conflorescence erect, secund, acropetal; floral rachis (25–) 80–220 mm long. Flower colour: perianth grey-green to silvery outside, dull to bright orange-yellow or reddish inside; style bright orange or yellow-orange. Perianth tomentose to villous outside. Pistil 23–36 mm long; style glabrous, with a slight dorsal hump below style-end. Follicle 14–21 mm long, villous with biramous hairs dominant and smaller erect simple glandular hairs scattered through.
Occurs in the monsoon tropics of northern Australia, in W.A. (Kimberleys), N.T. (N from c. 18ºS), and in northern Qld, extending S along the Great Divide to about Barcaldine. Grows in a wide range of habitats including eucalypt woodland, heath, and openings in sub-rainforest scrub; often in moister sites such as floodplains, near swamps or creeks but also on ridges and slopes; soils usually sandy or occasionally clay-loams. Flowers year round, but mainly May–Sept. Map 64.
W.A.: 56 km SW of Kalumburu Mission, N.H.Speck 4926 (CANB, PERTH); 17.5 km NE of Tableland Stn, M.Lazarides 6399 (CANB, NSW). N.T.: 208 km SE of Carlton [Hill] Stn [W.A.], R.A.Perry 3019 (AD, CANB, NSW, PERTH); Eva Valley Stn., C.Dunlop 3092 (DNA, K, L n.v. , MO n.v. ). Qld: Davies Creek forestry road c. 24 km E of Mareeba, Atherton Tableland, R.Schodde 3310 (A n.v. , AD, B n.v. , BRI, CANB, G, L n.v. , SING n.v. , WELT n.v. ).
Grevillea pteridifolia varies considerably in habit from a prostrate to bushy or spindly erect shrub, to a sizeable tree (especially in the W of the range). Olde & Marriott (Telopea 2: 115 (1995) usefully distinguish four forms, although not all populations are assignable to these. The 'typical form' occurs in Qld and N.T., and is a (?non-lignotuberous) fire-sensitive narrow-trunked shrub or tree with mostly smooth bark, narrow leaf lobes (usually < 3 mm wide), revolute leaf margins, and a slender style. The 'prostrate form' (e.g. J.R.Clarkson 5227 (BRI, K, NSW, QRS)) occurs in Qld on headlands and rocky peaks on Cape York N from c. 15ºS (parapatric with erect plants of the 'typical form'); it is a prostrate to procumbent shrub to 5 m across, with the habit retained in seedlings. The 'northern tree form', from northern N.T. and W.A., tends to develop with age a basal thickening of the stem akin to a lignotuber, and eventually a thick corky bark, allowing resprouting from the trunk and base after fire; the leaf lobes are variable in width and margins but are often coarse (> 3 mm wide) and recurved; the style is robust. A 'silver-leaved form' occurs in parts of Kakadu Natl Park, N.T., and has a persistent conspicuous appressed indumentum on the adaxial leaf surface; it is probably a minor local variant of the 'northern tree form'. Consistency of the features defining these forms is yet to be fully confirmed, as also the tendency for flower colour to deepen, and stylar diameter to increase, from the east to the west of the range.
The species is often prolific in favourable sites and the flowers are an important nectar source for animals and in Aboriginal culture. It sets copious amounts of seed and has weed potential overseas. Grevillea pteridifolia hybridises readily with several other species and is a parent of several commercial hybrids.
Data derived from Flora of Australia Volumes 16 (1995), 17A (2000) and 17B (1999), products of ABRS, ©Commonwealth of Australia