Eucalypts in harare



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Derivation of names: botanical - from Latin poly (much, many), plus bractea (bract), referring to bracts around young buds; common - refers to leaf colour and habit.
Taxonomy: Subgenus Symphyomyrtus.

Section Adnataria - (see E. intertexta).

Subsection Apicales - (see E. intertexta).

Series Buxeales - (see E. intertexta).

Subseries Continentes - outer operculum held until flowering; small to medium-sized trees, or mallees; some box bark always present [Latin continens (holding together) alludes to retention of outer operculum to flowering].

Supraspecies Moluccanae - valves of fruit 3-4; mallees or trees; bark rough on part or whole of stems or trunk; on hills or plains, rarely rocky sites.


Related species: supraspecies comprises 9 species:

E. persistens (slightly isolated from others); E. viridis and E. polybractea (very closely related); E. lansdowneana subsp albopurpurea (to be renamed) and E. odorata (very closely related); E. pilligaensis, E. microcarpa, E. moluccana, and

E. albens (very closely related). In earlier draft of class- fication Brooker listed subsp desquamata under E. polybractea.

General: a species of restricted distribution in two disjunct areas - south-central New South Wales and northern Victoria; wood formerly used by Aborigines for spear shafts, but of no commercial value today; however, species is valuable for oil production because of high concentration of cineole in leaves; production can be as high as 110 kg per ha per year, and species will coppice vigorously from lignotuber even after 20 years of repeated cutting back for oil harvesting. Introduced into Zimbabwe in 1980s for trial for oil production; planted in Mashonaland East, and at St Marnock's Farm, Mount Hampden, on outskirts of Harare.
EUCALYPTUS SIDEROPHLOIA Benth. Ironbark
Habit: medium-sized to tall forest tree with clear, straight bole to half or two-thirds of tree height; crown moderately heavily branched, but fairly open.

Bark: persistent on trunk and larger branches, grey to grey-black, hard, rough, deeply and coarsely furrowed, sometimes densely impregnated with kino.

Adult leaves: petiolate, alternate, lanceolate to broad-lanceolate, sometimes falcate, 80-150 x 10-23 mm, concolorous, green to grey-green, dull; venation faint but visible, lateral veins very fine, at 45-50 degrees to midrib, intra-marginal vein close to margin; reticulation very dense, with scattered oil glands.

Inflorescences: terminal panicles, 7-flowered; peduncles angular, 4-12 mm long; pedicels 2-4 mm long; buds spindle-shaped or diamond-shaped, up to 8 x 4 mm, scar present; operculum conical or beaked, about same length as hypanthium; flowers white, June-December.

Fruits: pedicellate, obconical, 6-8 x 5-7 mm; rim thick; disc prominent, descending, or slightly below rim level and flattish; valves usually 4, to rim level or slightly exserted; seed grey-brown.
Derivation of names: botanical - from Greek sideros (iron), plus phloios (bark), referring to very hard, rough bark; common - refers to bark.
Taxonomy: Subgenus Symphyomyrtus.

Section Adnataria - (see E. intertexta).

Subsection Apicales - (see E. intertexta).

Series Siderophloiae - ironbarks; outer operculum shed early; all stamens fertile, irregularly flexed.

Subseries Subglaucae - juvenile leaves petiolate, subglaucous; crowns of trees of adult leaves.
Related species: 20 species in subseries: E. decorticans,

E. granitica, E. rhombica (not closely related to each other or to others in subseries); E. fibrosa, E. siderophloia,

E. taurina, E. tholiformis, E. ophitica (very closely related just below supraspecies level); E. fracta (not closely related to any other); E. atrata, E. paedoglauca, E. xanthoclada,

E. quadricostata (very closely related); E. crebra,

E. beaniana, E. exilipes (very closely related); E. cullenii (not closely related to others); E. staigeriana, E. jensenii (very closely related); E. whitei (not closely related to others). Series Siderophloiae very imperfectly known.
General: E. siderophloia distributed along east coast of Australia, from central New South Wales northwards into southeastern Queensland; important timber species in Australia. Some confusion in southern Africa between this and E. paniculata because of superficial resemblance between them. Introduction into Zimbabwe obscure, but probably arrived in

about 1904; good specimens of E. siderophloia can be seen at

Runiville Post Office, in Highlands, Harare.


EUCALYPTUS CREBRA F. Muell. Narrow-leaved red ironbark
Habit: medium-sized woodland or forest tree, with well-formed bole up to two-thirds tree height; crown open, and rather straggly.

Bark: dark grey, hard, deeply and coarsely furrowed, persistent to small branches, often densely impregnated with kino.

Adult leaves: petiolate, alternate, narrow-lanceolate to lanceolate, 65-160 x 7-13 mm, concolorous, green to bluish green; venation faint or moderately visible, at 30-45 degrees to midrib, intramarginal vein distinct; reticulation dense, apparently glandless or with scattered to sparse oil glands.

Inflorescences: terminal panicles, 7-11-flowered; peduncles slender, terete to angular, 4-12 mm long; pedicels angular, 1-6 mm long; buds pedicellate, club-shaped to diamond-shaped, 3-8 x 2-4 mm, scar present; operculum conical or hemispher-ical, often apiculate; flowers white, May-December.

Fruits: pedicellate, cup-shaped, barrel-shaped, or hemi-spherical, 3-7 x 3-6 mm; rim usually thin; disc broad, descending; valves 3-4, to rim level or deeply enclosed; seed grey-brown.
Derivation of names: botanical - from Latin creber (crowded, frequent), possibly in allusion to species abundance in certain localities in natural range; common - refers to adult leaves, colour of wood, and bark type.
Taxonomy: Subgenus Symphyomyrtus.

Section Adnataria - (see E. intertexta).

Subsection Apicales - (see E. intertexta).

Series Siderophloiae - (see E. siderophloia).

Subseries Subglaucae - (see E. siderophloia).
Related species: subseries comprises 4 groups of very closely related species (just below supraspecies level), and 6 single species not closely related to each other or to groups (see

E. siderophloia). E. crebra related just below supraspecies level to E. beaniana and E. exilipes; earlier drafts of Brooker's classification indicate the still-unsettled status of E. drepanophylla as a subspecies of E. crebra or as a fourth closely related species in the E. crebra group.
General: species is widely distributed in eastern Australia from central New South Wales into York Peninsula, North Queensland, and from coast inland up to 500 km. Notoriously variable species because of wide geographical range, and requires comprehensive field and herbarium studies. Completely overlaps natural range of E. drepanophylla, giving rise to many intergrading forms between them. In common with other ironbarks, species is cut to provide timber for heavy engin-eering construction. Introduced into Zimbabwe around 1917, but usually found only as scattered specimens in stands of other species; one specimen known at Forest Research Centre, Highlands, Harare.
EUCALYPTUS STAIGERIANA F. Muell. ex Bailey Lemon-scented

ironbark
Habit: small to medium-sized tree; bole sometimes up to half or more of tree height, fairly straight, but often short, crooked; major branches usually steeply ascending to form framework of rather narrow, open crown.



Bark: ironbark, persistent to small branches, very hard, black, outer faces weathering whitish grey; branchlets yellow, often galucous.

Adult leaves: petiolate, alternate, ovate to broad-lanceolate, 90-140 x 15-30 mm, concolorous, dull blue-green to glaucous, firm, strongly lemon-scented when crushed; venation not readily visible to naked eye, lateral veins few, at 40-45 degrees to midrib; intramarginbal vein remote; reticulation dense, fine, with numerous oil glands.

Inflorescences: terminal panicles, 7-11-flowered; some text-books indicate inflorescences may be terminal panicles or axillary umbels; peduncles somewhat flattened, 2-13 mm long; pedicels 2-10 mm long; buds pedicellate, spindle-shaped or nearly double conical, 7 x 4 mm, scar present; operculum conical to beaked; flowers white, December-February.

Fruits: pedicellate, cup-shaped, 5-6 x 4-5 mm; rim thin; disc narrow, descending; valves 3-4, to rim level; seed grey-brown.
Derivation of names: botanical - in honour of Karl Theodore Staiger, Government Analytical Chemist in Queensland, who did investigations into chemistry of many native plants; common - refers to strong lemon scent of leaves, and to nature of bark.
Taxonomy: Subgenus Symphyomyrtus.

Section Adnataria - (see E. intertexta).

Subsection Apicales - (see E. intertexta).

Series Siderophloiae - (see E. siderophloia).

Subseries Subglaucae - (see E. siderophloia).
Related species: subseries comprises 4 groups of very closely related species (just below supraspecies level), and 6 single species not closely related to each other or to groups (see

E. siderophloia). E. staigeriana most closely related just below supraspecies level to E. jensenii.
General: a Queensland endemic with restricted occurrence in Cape York Peninsula, on granite or sandstone hills, never coastal; wood locally useful but not commercially important; E. staigeriana and E. citriodora (Subgenus Corymbia) only two species in entire genus having essential oils with citronellal content. Introduced into Zimbabwe in 1940s and planted in small plot at Mtao Forest, near Mvuma; reintroduced in 1980s for trials for oil production, planted in Mashonaland East and on outskirts of Harare at St Marnock's Farm, Mount Hampden.


EUCALYPTUS POLYANTHEMOS Schauer Red box
Habit: small to medium-sized woodland tree; short, somewhat crooked bole; dense, rounded crown.

Bark: very variable; sometimes shed from trunk and branches in irregular short strips, leaving grey, cream, white, or pinkish surface; sometimes retained over much of trunk and branches as subfibrous to fibrous box-type, brownish or greyish, rough bark.

Adult leaves: petiolate, alternate, ovate, elliptical, or broad-lanceolate, 55-90 x 15-35 mm, concolorous, slate-grey or bluish green, dull, firm; venation moderately conspicuous, at 20-40 degrees to midrib; intramarginal vein remote from margin; reticulation dense, numerous oil glands.

Inflorescences: terminal panicles, 7-flowered; peduncles slender, terete, 5-15 mm long; pedicels angular, 1-9 mm long, angles continuing as faint ribs along hypanthia; buds ovoid, club-shaped, or diamond-shaped, 5-6 x 3-4 mm, scar present; operculum conical or more or less hemispherical-apiculate, usually narrower than hypanthium at join; flowers white, August-December.

Fruits: pedicellate, pear-shaped, obconical, or barrel-shaped, 4-7 x 3-6 mm, usually glaucous; rim thin, often split; disc relatively broad, vertically or obliquely descending; valves 4 (3-5), enclosed; seed grey-brown.
Derivation of names: botanical - from Greek poly- (much, many), plus anthemon (flower), referring to numerous flower buds in each panicle; common - refers to wood colour and to box group of eucalypts.
Taxonomy: Subgenus Symphyomyrtus.

Section Adnataria - (see E. intertexta).

Subsection Terminales - named from anthers opening in terminal pores - stamens inflexed; many fertile anthers deflected sideways by pressure in unopened bud configuration; staminodes present.

Series Heterophloiae - box-barked, smooth-barked, or with rough, loose, flaky bark; inflorescences mostly terminal; outer operculum shed early.


Related species: 7 species in series: E. hypostomatica,

E. rudderi, E. conica (very closely related at just below supraspecies level); E. baueriana, E. polyanthemos,

E. fasciculosa, E. lucens (not very closely related to each other or to first group of 3); first 4 species box-barked,

E. polyanthemos with variable bark, E. fasciculosa mainly smooth-barked, E. lucens completely smooth; in earlier draft of classification Brooker listed 2 atypical subspecies of

E. polyanthemos, subsp vestita and subsp longior.
General: widely distributed in central and eastern Victoria, and south-central New South Wales; wood used locally for fencing and fuel. Introduced into Zimbabwe around 1907; 1920s planting still survives in arboretum at Mtao Forest, near Mvuma. One specimen in National Botanic Garden, Harare, near toilet block at main car park. E. polyanthemos essential oil has high cineole content; may have medicinal potential.
EUCALYPTUS PANICULATA Smith Grey ironbark
Habit: medium-sized to tall forest tree; long, well-formed bole; usually heavy, compact crown.

Bark: light grey, but often impregnated with kino, hard, deeply furrowed and ridged, persistent to small branches.

Adult leaves: petiolate, alternate, lanceolate, 95-150 x

12-24 mm, discolorous, green, slightly glossy above, thin; venation moderately visible, at 35-45 degrees to midrib; densely reticulate, oil glands present.



Inflorescences: terminal panicles, 7-flowered; peduncles slender, angular or flattened, 6-16 mm long; pedicels strongly angular, 2-10 mm long, angles continuing as ribs along hypanthia; buds ovoid to diamond-shaped, 8-11 x 4-5 mm; operculum conical, often narrower than hypanthium at join, scar present; flowers white, June-January, outer stamens with- out anthers (staminodes).

Fruits: pedicellate, ovoid, hemispherical, obconical, or pear-shaped, 5-9 x 5-7 mm, usually faintly ribbed; rim thick; disc more or less level or descending, usually obscured by staminal ring; valves usually 5, about rim level or slightly enclosed; seed grey-brown.
Derivation of names: botanical - from paniculate infloresc- ences; common - from bark colour and type.
Taxonomy: Subgenus Symphyomyrtus.

Section Adnataria - (see E. intertexta).

Subsection Terminales - (see E. polyanthemos).

Series Discolores - named from discolorous adult leaves.


Related species: 6 species in series: E. paniculata,

E. fergusonii subsp dorsiventralis (to be renamed),

E. fergusonii subsp fergusonii (all very closely related at just below supraspecies level); E. decolor, E. ancophila,

E. placita (not very closely related to each other or to first group of 3). In earlier draft of classification Brooker had 2 atypical subspecies of E. paniculata, subsp matutina and fergusonii, but in final draft E. fergusonii reinstated as species with footnote indicating that it may be genetically submerged within E. paniculata.
General: a New South Wales endemic, occurring in narrow strip, 80 km wide x 450 km long, in central coastal region;

an important timber species in Australia; wood among hardest and heaviest of all eucalypts, density 1120 kg per cubic metre (cf Guaicum officinale, lignum vitae, with a density of 1250). Introduced into Zimbabwe about 1904; planted quite widely as amenity and shelterbelt tree; grown commercially at Mtao Forest, near Mvuma until mid-1960s; good specimens at Harare Forest Nursery, off Orange Grove Drive, Highlands, probably dating from 1913-1920. See note under E. siderophloia on mixing of the two species, and some confusion between them.




EUCALYPTUS SIDEROXYLON A. Cunn. ex Woolls Red ironbark
Habit: small to medium-sized woodland or forest tree; bole often poorly formed and not exceeding one-half of tree height; crown development poor in typical dry habit.

Bark: dark brown to black, persistent to small branches, often impregnated with kino deposits; smaller branches smooth, whitish or light grey.

Adult leaves: petiolate, alternate, lanceolate or narrow-lanceolate, 70-140 x 12-18 mm, concolorous, dull green, glaucous, or slaty grey; venation moderately visible, at 25-40 degrees to midrib, intramarginal vein distinct; densely reticulate, numerous oil glands.

Inflorescences: axillary, simple, 7-flowered (sometimes 9); peduncles slender or angular, 7-20 mm long; pedicels slender or angular, 2-15 mm long, angles continuing as faint ribs on hypanthia; buds ovoid, club-shaped, or diamond-shaped, some-times warty, 7-12 x 4-5 mm, no scar; operculum conical or beaked; flowers white, pink, red, or pale yellow, April-September; outer stamens without anthers (staminodes).

Fruits: on long slender pedicels, cup-shaped, barrel-shaped, or truncate-globose, sometimes slightly urn-shaped, 5-11 x

6-10 mm; rim thick; disc relatively broad, descending, often obscured by staminal ring; valves usually 5, deeply enclosed; seed grey-brown.


Derivation of names: botanical - from Greek sideros (iron), plus xylon (wood), referring to hardness of wood, although by no means hardest in genus; common - refers to wood colour and to bark type.
Taxonomy: Subgenus Symphyomyrtus.

Section Adnataria - (see E. intertexta).

Subsection Terminales - (see E. polyanthemos).

Series Melliodorae - inflorescences mostly axillary; outer operculum held until flowering; staminophore broad; with outer staminodes; valves of fruit (4) 5 or 6 (7).

Subseries Solidae - from Latin solidus (dense, hard), alluding to hard, furrowed ironbark.
Related species: only 2 species in subseries, E. sideroxylon and E. tricarpa, very closely related at just below supra- species level; latter at one time classified as subspecies of former, and distinguished by larger size, better bole form, 3-flowered inflorescences, larger buds, and larger fruits.
General: E. sideroxylon widely distributed from southeastern Queensland to northeastern Victoria, rarely coastal, extends considerable distance inland in New South Wales; wood used for heavy engineering, but not a major commercial species; leaves yield oil with high cineole content for medicinal use.

Introduced into Zimbabwe around 1917; scattered trees may be seen in many parts of highveld, always easily recognized by thick black bark (a few specimens, eg at La Rochelle Botanical Garden near Mutare, have been noted with dark grey bark, rather than black). No actual specimens known within Harare City limits, but almost certain to be present because species was formerly quite commonly planted for ornament.


EUCALYPTUS MELLIODORA A. Cunn. ex Schauer Yellow box
Habit: medium-sized woodland or forest tree; bole one-third or more of tree height; crown large, spreading; smaller branches often pendulous.

Bark: rough, persistent on lower part of trunk, and for varying lengths of upper trunk and main branches; occasion- ally shed in irregular scales or strips down to ground level; grey, yellow-brown, or red-brown, subfibrous, becoming darker, harder, coarser with age.

Adult leaves: petiolate, alternate, narrow-lanceolate to lanceolate, 65-135 x 8-18 mm, concolorous, grey-green; venation prominent, at 20-40 degrees to midrib, intramarginal vein well in from margin, occasionally second intramarginal vein present near base of leaf; reticulation dense, numerous oil glands.

Inflorescences: usually axillary, simple, often clustered towards tips of branchlets to give appearance of being panicles; peduncles slender, more or less terete to angular, 3-11 mm long; pedicels angular, 2-9 mm long; buds club-shaped, diamond-shaped, or ovoid, 5-8 x 3-4 mm, no scar (two opercula intact); operculum conical or beaked; flowers white, sometimes pink, October-January; outer stamens without anthers (staminodes).

Fruits: pedicellate, ovoid, hemispherical, pear-shaped, or truncate-globose, 4-7 x 4-7 mm; rim thick; disc descending, often obscured by black staminal ring; valves usually 5, about rim level or enclosed; seed grey-brown.
Derivation of names: botanical - from Latin melleus (honey), and odora (smelling), referring to abundant nectar; common - probably refers to bark colour (although very variable), and to box group of eucalypts.
Taxonomy: Subgenus Symphyomyrtus.

Section Adnataria - (see E. intertexta).

Subsection Terminales - (see E. polyanthemos).

Series Melliodorae - (see E. sideroxylon).

Subseries Leucoxyla - white or smooth-barked ironbarks (bark actually smooth or fibrous).
Related species: 3 species in subseries: E. melliodora,

E. leucoxylon, E. petiolaris, not very closely related to each other.
General: species occurs abundantly in Victoria and New South Wales, especially on inland side of Great Dividing Range; more scattered in southeast Queensland; wood hard and heavy, used for heavy engineering construction, railway sleepers, poles, etc, and produces excellent firewood; regarded as best eucalypt for honey production. Introduced into Zimbabwe about 1917, but never much planted; scattered old trees occasionally seen in Mashonaland and Midlands; fairly large group of trees may be seen in grounds of ZRP quarters at Highlands Police Station in Harare.

EUCALYPTUS MICROCORYS F. Muell. Tallowwood
Habit: medium-sized to very tall forest tree; bole usually straight, well formed, to two-thirds of tree height; moderately open to dense crown.

Bark: rough, persistent to small branches, brown to red-brown, soft, fibrous, often with surface pores and horizontal cracks on under-layers.

Adult leaves: petiolate, alternate, lanceolate, tapering to long fine point, 80-130 x 15-25 mm, discolorous, glossy dark green above, thin, edges slightly crenulate; venation moderately visible, at 45-60 degrees to midrib, intramarginal vein distinct, scalloped; reticulation moderate to dense, oil glands numerous.

Inflorescences: axillary, simple, 7(9)-flowered, often clustered towards ends of branches to resemble panicle; peduncles slender, flattened, 6-18 mm long; pedicels more or less angular, though often not really distinct at bud stage due to gradual tapering into hypanthia, 2-7 mm long, angles often continuing as faint ribs along hypanthia; buds on long slender tapering pedicels, club-shaped, 4-6 x 2-3 mm, no scar although 4 minute sepals shed early; operculum hemispherical with conspicuous cross sutures; stamens in 4 clusters, outer ones without anthers (staminodes); flowers creamy white, July-October.

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