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Eucalyptus albida Maiden & Blakely, J. & Proc. Roy. Soc.
New South Wales 59: 175 (1925).
T: Harrismith, W.A., 6 Mar. 1924, C.A.Gardner 2113; holo: NSW;
iso: MEL, PERTH.
Mallee to 3 m tall. Forming a lignotuber.
Bark smooth throughout, often powdery, white to cream over
grey.
Branchlets lacking oil glands in the pith.
Juvenile growth (coppice or field seedlings to 50 cm):
stems rounded in cross-section, glaucous; juvenile leaves sessile,
opposite for many nodes, orbicular to cordate, 1.5-4 cm long, 1.3-3.5
cm wide, base amplexicaul, apex rounded often with a small point,
white with wax.
Adult leaves alternate, petioles 0.7-1.7 cm long; blade narrowly
lanceolate to narrowly elliptical-oblong, (4)5-7.5(10.5) cm long,
0.5-1.7 cm wide, base tapering to petiole, margin entire, apex finely
pointed, concolorous, very glossy, dark green, side-veins
greater than 45° to midrib,
reticulation dense, intramarginal vein close to margin, oil glands
large, numerous, intersectional.
Inflorescences axillary unbranched, peduncles 0.5-1.5 cm long;
buds 7 or 9, pedicellate bluntly ovoid to diamond-shaped, scar present,
operculum conical to rounded but with a flattened apex, stamens usually
inflexed or with a few irregularly placed, anthers cuneate-cuboid,
adnate to filament apex (rigidly basifixed), dehiscing by sub-terminal
pores, a few of the innermost stamens imperfectly formed, style long
and conspicuously twisted apically, stigma tapered, locules 3(4),
the placentae each with 4 vertical rows of ovules; flowers creamy
white.
Fruit pedicellate, hemispherical to obconical, 0.5-0.8 cm wide,
disc descending, valves 3(4), held near rim level .
Seed brown-grey, 1-2.5 mm long, flattened-ovoid, often pointed
at one end, dorsal surface frequently longitudinally furrowed but
surface smooth, hilum ventral.
Cultivated seedling (measured at node 10): cotyledons Y-shaped
(bisected); stems rounded to squared
in cross-section, glaucous; leaves sessile and opposite for at least
28 nodes, successive nodes closely spaced and leaves therefore overlapping,
first pairs oblong then becoming cordate or orbicular, 1.3-3 cm long,
1-2.5 cm wide, base amplexicaul, apex rounded-apiculate or pointed,
white-grey with copious wax
NOTES
Eucalyptus albida (Latin, albidus,
whitish, referring to the juvenile leaves)
A smooth-barked mallee endemic to Western Australia, found principally
in the southern wheatbelt from Tammin and Narrogin east to Hyden and
Ravensthorpe but with a small occurrence in the northern sandplains
near Badgingarra. It is an emergent mallee in heath on white sands.
The transition from very conspicuous, sessile, orbicular to cordate,
white, waxy juvenile growth to narrowly lanceolate glossy green adult
foliage is quite abrupt. The buds have an obtusely conical operculum
and the style (easily seen in the immature fruit) is always twisted
at the top.
It belongs in Eucalyptus sub-genus Symphyomyrtus section
Bisectae sub-section Destitutae because the buds have
two opercula, cotyledons are Y-shaped and branchlets lack oil glands
in the pith. Within this sub-section E. albida belongs to a
group of about 16 species, series Porantherae, that are further
characterized by having anthers completely adnate to the staminal
filaments, strongly inflexed stamens, densely reticulate leaves with
intersectional oil glands and by the fruit with a distinct thick rim
that includes a whitish descending disc. The small, glossy leaves
of species in series Porantherae may result in confusion with
species in series Heterostemones, however the fruit alone usually
distinguish the series. The fruit of series Heterostemones
are thin-rimmed.
E. albida has the glossiest leaves of the species in the series,
the juvenile leaves the whitest and the twisted style character always
occurs. Within its area of distribution it is most likely to be confused
with E. dissimulata which has similar blunt buds but elliptical
grey-green (non-glaucous) juvenile leaves and a straight style. E.
hypochlamydea , a related species found mainly in the northern
and central wheatbelt but extending south to about Wagin and east
to the goldfields, has beaked buds and glaucous orbicular slightly
warty juvenile leaves and rarely has a twisted style.
Coppice-growth of E. albida is used in dried flower arrangements
because of spectacular white round leaves.
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