Acacia brumalis

Acacia brumalis Maslin, Nuytsia 10: 185 (1995)

Shrub or tree 2–3 m high. Branchlets sometimes red, glabrous. Phyllodes patent to ascending, variable in shape and size, commonly oblanceolate to narrowly elliptic or oblong-elliptic, sometimes linear, straight to shallowly incurved, mostly 5–13 cm long, 4–20 mm wide, narrowed at base, rather firm and coriaceous, glabrous, 1-nerved per face; lateral nerves obscure; glands not prominent, 1–2, the lowermost usually 2– 30 mm above pulvinus. Inflorescences racemose; raceme axes 0.6–4 cm long, appressed-puberulous with golden or white hairs, sometimes glabrous in fruit; peduncles normally 3–5 mm long, with indumentum as on raceme axes; heads globular to slightly obloid, 5–8 mm diam. at anthesis, 17–45-flowered, golden. Flowers 5-merous; sepals 5/6-united. Pods linear, usually straight-edged to slightly constricted between seeds, to 10 cm long, 5–6 mm wide, thinly coriaceous to firmly chartaceous, dark coloured, glabrous. Seeds longitudinal, oblong to elliptic, 4–5 mm long, dull, black; funicle encircling seed in a single fold, light reddish brown, yellow when fresh; aril thick.

Most common from Regans Ford (on the Moore R. N of Perth) and Wubin (c. 20 km N of Dalwallinu) S to near Hyden, but also extending N to near Morowa and near Northampton, south-western W.A. Flowers late May- Sept.

A member of the ‘ Acacia microbotrya group’ formerly confounded with A. microbotrya which has broader, moniliform pods with larger seeds, usually cream to pale yellow flower-heads which reach anthesis earlier in the season, solitary glands and generally falcate, thinner and often pendulous phyllodes. See also under the variants below.

Very polymorphic and may well comprise more than one taxon. Much of the variation is accommodated by the following variants, but much work is needed to elucidate the complex patterns of morphological variation and to clarify the relationship between this species and its equally variable close relatives A. chrysella , A. chamaeleon and A. microbotrya .

Acacia brumalis Maslin (typical variant)

The typical variant has phyllodes that are oblanceolate to narrowly oblanceolate or narrowly elliptic to narrowly oblong-elliptic, normally straight, normally 5–9 cm long, 5–10 mm wide, subglaucous to glaucous, and a gland 1–3 cm above the pulvinus. It has 17–25 flowers per head. This variant occurs from Regans Ford, Goomalling and Pithara (which is c. 13 km due S of Dalwallinu) areas E to the Koorda- Wyalkatchem area, also near Northampton and SE of Hyden. Specimens from near Northampton have pods which are a little more constricted between the seeds than normal but otherwise they seem typical of this variant. This variant is frequently found growing in saline areas (W.A.: Swan R., J.Drummond 2:142 (BM, K, LUND, OXF, P, W) and 291 (BM, G, K, MEL, OXF, P, W); Dragon Rocks Reserve, S.D.Hopper 5244 (PERTH); 8.8 km SW of Goomalling towards Toodyay, B.R.Maslin 2017 (CANB, K, MEL, NY, PERTH); c. 25 km W of Northampton, P.C.Ryan 101 (PERTH)).

Acacia brumalis Maslin (oblanceolate phyllode variant)

The second variant has phyllodes that are narrowly oblanceolate, 5–10 cm long, 6–20 mm wide, obtuse, glaucous to subglaucous, and a gland that is normally 2–10 mm above the pulvinus. It has 30–45 flowers per head. This variant occurs from Cowcowing (c. 20 km due NNE of Wyalkatchem) SE to near Hyden (W.A.: 11.6 km E of Merredin on Great Eastern Hwy to Kalgoorlie, N.Hall H76/41 (PERTH); 13.6 km E of Hyden on the L. Varley road, B.R.Maslin 535 (AD, PERTH); 10 km N of Wyalkatchem towards Koorda, B.R.Maslin 4103 (CANB, K, MEL, PERTH)). This variant may resemble A. steedmanii and the oblanceolate phyllode variant of A. chamaeleon ; may also resemble A. jennerae which is distinguished by its broader pods, usually glabrous raceme axes and peduncles, frequently obviously acuminate phyllodes and larger seeds.

Acacia brumalis Maslin (incurved phyllode variant)

The third variant has phyllodes that are linear to narrowly oblanceolate, normally shallowly and uniformly incurved, 8–12 cm long, 4–8 mm wide, green to subglaucous, and a gland 1–3 (- 5) cm above the pulvinus. It has 18–30 flowers per head. This variant is closely allied to the third variant under A. chrysella . It occurs mainly in the Wubin- Pithara- Kalannie area (near Dalwallinu), and N to near Morowa (W.A.: 6 km N of Wubin towards Latham, B.R.Maslin 4131 (CANB, K, MEL, PERTH); Gutha, 5 Apr. 1934, K.W.McLean (PERTH); 35 km E of Perenjori, A.A.Mitchell 1532 (PERTH); Buntine Reserve, 10.5 km N of Wubin, B.G.Muir 188 (PERTH)).

Acacia brumalis Maslin (light land variant)

The fourth variant was not included in the Fl. Australia treatment of Acacia . Based on morphological criteria it is suspected that it may be a hybrid between A. microbotrya var. borealis and A. affin. jennerae . Characters suggesting hybrid origin include its wide variation in phyllode width and the fact that the peduncles and raceme axes vary from glabrous to appressed-hairy. Salient features of this variant include the following: Bushy shrubs 2–3 m tall, sometimes clonal due to root suckering. Branchlets bronze or dull reddish on upper (exposed) surface, commonly greenish below. Phyllodes variable in shape and size (even on a single plant), most tending towards narrowly oblanceolate, obtuse to (when narrow) acuminate, 7–12 (–14) cm long, (4–) 5–17 (–22) mm wide, dull green or sub-glaucous; gland 15–40 mm above pulvinus. Raceme axes and peduncles glabrous to minutely appressed-hairy; heads c. 30-flowered (few heads seen). Pods linear to sub-moniliform, 6–18 cm long, 4–7 mm wide. Seeds 4–6 long; funicle 3/4 encircling the seed. It is confined to a few populations in the Kalannie region, south-west W.A. where it occurs in light brown or yellow-brown sandy loam, with some gravel, on the lower slopes of rises high in the landscape. (W.A.: about 40 km due NE of Kalannie, B.R.Maslin 7571 (PERTH)).

Type of accepted name

Mortlock R., c. 12 km S of Goomalling towards Toodyay, W.A., 27 Aug. 1976, B.R.Maslin 4198 ; holo: PERTH; iso: CANB, K, MEL, NY.

Synonymy

[ Acacia leiophylla auct. non Benth.: C.F.Meisner, in J.G.C.Lehmann, Pl. Preiss . 2: 203 (1848)]

(BRM)

The Fl. Australia treatment of A. brumalis has been modified here in WATTLE to include the Light Land Variant of the species which was described in B.R.Maslin (1998), Wattle of the Kalannie region: thieir identification, characteristics and utilisation. CDROM Publication. (Department of Conservation and Land Management: Perth.)

The information presented here originally appeared on the WATTLE CD-ROM which was jointly published by the Australian Biological Resources Study, Canberra, and the Department of Parks and Wildlife, Perth; it was produced by CSIRO Publishing from where it is available for purchase. The WATTLE custodians are thanked for allowing us to post this information here.