Eucalypts in harare

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EUCALYPTUS PROPINQUA Deane & Maiden Grey gum
Habit: medium-sized to tall forest tree, typically well formed, with bole up to half or two-thirds of tree height; crown moderately small, open.

Bark: decorticating to ground level in large irregular patches, exposing fresh cream- or orange-coloured bark that weathers to light mottled grey, then dark or grey-brown, finally with matt or granular surface.

Adult leaves: petiolate, alternate, lanceolate, 80-140 x

12-27 mm, discolorous, dull or glossy green above, paler below, comparatively thick; venation fine but visible, regular, at 45-55 degrees to midrib, intramarginal vein close to margin; densely reticulate, oil glands numerous.

Inflorescences: mostly axillary and simple, but sometimes apparently compound and terminal, 7-15-flowered; peduncles slender, angular or flattened, 5-15 mm long; pedicels angular, 2-5 mm long; buds ovoid or club-shaped, 4-5 x 3-4 mm, often with ribs on hypanthia continued from pedicels, scar present; operculum hemispherical to conical; flowers white, December-March.

Fruits: on short pedicels, hemispherical or broadly obcon- ical, often with ribbed hypanthia, 2-5 x 3-6 mm; rim thick; disc moderately broad, level or ascending; valves 3-4, exserted, a whitish skin often visible over disc and valves; seed brown.
Derivation of names: botanical - from Latin propinqus (near, related), referring to bark, which is similar to that of

E. punctata; common - refers to predominant colour of bark.
Taxonomy: Subgenus Symphyomyrtus.

Section Latoangulata - (see E. grandis).

Series Lepidotae-Fimbriatae - grey gums - bark smooth, mottled, becoming granular in texture; inflorescences some-times terminal; ovules in 4-6 vertical rows; valves of fruit prominent; seeds pyramidal; hilum terminal.
Related species: series comprises 6 species in two groups of near-supraspecies level, (1) E. major, E. propinqua, and (2) E.biturbinata, E.canaliculata, E.punctata, E.longirostrata. Of these, only E. major and E. canaliculata have not been introduced into Zimbabwe.
General: a species of coastal eastern Australia from south-eastern Queensland to central New South Wales; a prime structural timber for heavy engineering. Almost certainly an early introduction into Zimbabwe, but records are obscure as a result of former confusion with E. punctata; many stands nominally of E. punctata were often mainly E. propinqua. Both species formerly planted commercially, and today not infrequently encountered in Mashonaland. Because of ready availability of seed for raising in nurseries it is likely that E. propinqua has been planted in Harare in the past, but only one positive record exists, and no actual specimens are known to me at the present time.

Habit: Medium-sized woodland or forest tree, at its best with a well-formed bole, often reduced to poorly formed tree with short bole and much-branched crown.

Bark: decorticating to ground level in large irregular plates, newly exposed bark cream-coloured to light orange, even coppery, weathering to grey, dark grey, or grey-brown, finally with a matt or granular surface.

Adult leaves: petiolate, alternate, lanceolate to broad-lanceolate, sometimes slightly falcate, 85-140 x 16-30 mm, discolorous, glossy dark green above, paler below; venation parallel, close together, at 45-55 degrees to midrib; densely reticulate, numerous oil glands.

Inflorescences: mostly axillary, simple, but some apparently terminal and compound may be present, 7-flowered, very occas-ionally 9-flowered; peduncles angular or flattened, 5-20 mm long; pedicels usually angular, 2-9 mm long; buds with hemi-spherical to obconical, often ribbed or angled hypanthia,

7-16 x 4-6 mm, scar present; operculum conical, rounded, or beaked; flowers white, January-April.

Fruits: distinctly pedicellate, cup-shaped, or hemispherical, 5-12 x 5-14 mm; rim thick; disc level or slightly ascending; valves 3-4, deltoid, often robust, slightly to strongly exserted, often with remnants of whitish skin attached; seed black.
Derivation of names: botanical - from Latin punctatus (dotted, spotted), referring to leaf glands; common refers to predom-inant colour of bark.
Taxonomy: Subgenus Symphyomyrtus.

Section Latoangulata - (see E. grandis).

Series Lepidotae-Fimbriatae - (see E. propinqua).
Related species: E. punctata very closely related to

E. biturbinata, E. canaliculata, and E. longirostrata, the four of them falling just short of being recognized at supra-species level. Two other species in the series, E. major and E. propinqua, are less closely related.
General: a New South Wales endemic, occurring in relatively small region 150 km north and south of Sydney, and from coast to 100-150 km inland; not important commercially, but wood is used locally for heavy construction and railway sleepers. Introduced into Zimbabwe about 1904 and planted in Rhodes Matopos Estate; grown commercially at Mtao Forest from 1920s to 1950s, and present in many woodlots in Mashonaland, often mixed with E. propinqua. Almost certainly present in Harare,

but no actual specimens known to me. Two close relatives,

E. biturbinata and E. longirostrata, have been introduced into Zimbabwe, but only the latter known to be present today - at Mountain Home, near Penhalonga.

Habit: medium-sized to tall forest tree, usually with well-formed bole up to half tree height; crown somewhat irregularly but heavily branched, smaller branches having pendulous habit.

Bark: rough, persistent over whole trunk and large branches, grey, subfibrous or flaky, irregularly ridged and cracked, tending to be thin; shed from smaller branches in irregular flakes, leaving them smooth, fawn-coloured, or greenish.

Adult leaves: petiolate, alternate, falcate to lanceolate or narrow-lanceolate, 110-240 x 25-40 mm, concolorous, green or grey-green, dull, moderately thick; venation easily visible, regular, at 35-50 degrees to midrib, intra-marginal vein distinct; moderately to densely reticulate, oil glands very numerous.

Inflorescences: axillary, simple, 3-flowered; peduncles slender, terete to slightly angular, often pendulous, 11-34 mm long; pedicels 4-20 mm long; buds double-conic, 15-26 x 6-12 mm, often with faintly ribbed hypanthia, scar present; operc-ulum conical, sometimes beaked; flowers white, October-November.

Fruits: with long peduncles, 10-17 x 9-16 mm, cup-shaped, cylindrical, or slightly bell-shaped; rim thick; disc very broad, descending; valves usually 4, erect, about rim level or slightly below; seed black.
Derivation of names: botanical - from Latin longus (long), and folius (leaf); common - refers to bark.
Taxonomy: Subgenus Symphyomyrtus.

Section Similares (from Latin similaris, similar, alluding to same colour on both sides of leaf, ie concolorous).

Related species: the only species in its section, no close relatives; an apparently anomalous species in Pryor and Johnson's classification, and its present assignment to a monotypic section appears to be more appropriate.
General: a New South Wales endemic, occurring in narrow strip, mainly less than 70 km wide, along southern coast; not commercially important, but hard red wood used locally.

Introduced into Zimbabwe prior to 1902 and planted at site of present-day Harare International Airport, also at site of Forest Research Centre, where a few trees still exist along proposed route of Newlands bypass road. A rare eucalypt in Zimbabwe, and probably introduced by accident rather than by design. A few trees known to be present at Mountain Home, near Penhalonga.

Habit: medium-sized to tall forest tree, often with well-formed bole to half of tree height, and always with steeply ascending branch habit; crown large, somewhat open.

Bark: decorticating over whole trunk in large irregular plates or flakes to leave a somewhat matt or mottled surface of white, grey, dark grey, and bluish grey.

Adult leaves: petiolate, alternate, lanceolate to narrow-lanceolate, 100-200 x10-27 mm, concolorous, green; venation conspicuous, at 40-55 degrees to midrib, intramarginal vein distinct; moderately reticulate, numerous yellow and green oil glands.

Inflorescences: axillary, simple, 7-11-flowered; peduncles angular, 7-25 mm long; pedicels 3-10 mm long; buds elong- ated, 9-20 x 4-5 mm, scar present; operculum horn-shaped, 2-7 times as long as hypanthium; flowers white, present almost year round in Zimbabwe. [A number of specimens in Zimbabwe have been observed to shed outer operculum fairly late in bud development, sometimes when bud is almost fully developed.]

Fruits: pedicellate, more or less hemispherical (ovoid including disc), 3-6 x 4-8 mm; rim thick; disc broad, ascending; valves 4, occasionally 5, strongly exserted; seed brown-black.
Derivation of names: botanical - from Latin teretus (terete, circular in cross-section, tapering or narrowly conical), and cornu (horn), referring to shape of operculum; common - refers to forest habitat and colour of wood.
Taxonomy: Subgenus Symphyomyrtus.

Section Exsertaria - adult leaves concolorous; ovules in 6 or 8 vertical rows; valves of mature fruit strongly exserted; edge of inner seed coat toothed.

Series Erythroxyla - red gums - bark smooth, mottled; leaves with moderately dense reticulation; oil glands present; juvenile leaves broadly ovate to lanceolate; disc united to ovary roof; most stamens erect; seeds brown to black, elongated, hilum terminal; wood red.
Related species: series comprises 15 species: E. nandewarica

(somewhat isolated); E. dwyeri, E. dealbata, E. vicina (very closely related); E. flindersii, E. nudicaulis, E. gillenii (very closely related); E. infera (somewhat isolated);

E. terrica, E. chloroclada, E. blakelyi, E. kabiana (very closely related); E. glaucina, E. amplifolia, E. tereticornis (very closely related). Of the above, only E. blakelyi and

E. tereticornis introduced into Zimbabwe.
General: E. tereticornis has widest latitudinal range of any eucalypt, occurring through 28 degrees of latitude from southeastern Victoria into southeastern Papua New Guinea; on Australian mainland occurrence is along east coast to 400 km inland; in spite of huge natural range only one subspecies described; not major commercial timber species, but wood is used locally where abundant. Species introduced into Zimbabwe before 1902; common in Harare, particularly in old municipal plantations; fine specimen at Harare Forest Nursery, and very large tree at corner of Cambridge and Ceres Roads in Avondale.

Habit: medium-sized to tall tree, with large, often pendulous crown; bole usually short and thick.

Bark: decorticating over whole trunk, or sometimes adhering to base of trunk in irregular, longitudinal, grey scales; otherwise smooth, white, pale grey, or buff, with grey and reddish patches, shedding in strips or irregular flakes.

Adult leaves: petiolate, alternate, lanceolate or narrow-lanceolate, 80-300 x 7-20 mm, green or grey-green, concolor- ous, dull on both surfaces, thin, pendulous; venation moderately visible to conspicuous, at 40-50 degrees to midrib, intramarginal vein distinct; moderate reticulation, numerous yellow, green, and clear oil glands.

Inflorescences: axillary, simple, 7-11-flowered; peduncles angular, usually slender, 5-25 mm long; pedicels 1-10 mm long; buds 5-11 x 3-5 mm, with hemispherical hypanthia, sometimes very squat, scar present; operculum strongly beaked in south-ern forms, conical in northern forms; flowers white, present more or less year round in Zimbabwe.

Fruits: pedicellate, ovoid (including disc), or truncate-globular, 5-8 x 5-8 mm; rim thick; disc broad, ascending; valves 3-5, usually 4, strongly exserted, usually curving inwards; seed yellow.
Derivation of names: botanical - after Camalduli, district in Tuscany, Italy, from where cultivated specimen was described to provide first valid name; common - refers to riverine habitat and colour of wood.
Taxonomy: Subgenus Symphyomyrtus.

Section Exsertaria - (see E. tereticornis),

Series Rostratae - red gums - bark smooth, mottled; leaves with moderate to dense reticulation; oil glands present; juvenile leaves lanceolate; stamens erect or inflexed; seeds yellow to yellow-brown, cuboid, with double seed coat; hilum terminal [series name refers to rostrate (beaked) operculum].
Related species: only species in series, no close relatives; 3 subspecies recognized, camaldulensis (southeastern Austr- alia), obtusa (northern Australia), and simulata (Cape York peninsula); latter has long operculum of E. tereticornis, but seed and juvenile leaves typical of E. camaldulensis.
General: E. camaldulensis has widest geographic range of any eucalypt, occurring in all Australian mainland states; also most widely planted eucalypt in the world. Introduced into Zimbabwe 1897-98; quickly became a common woodlot tree in drier regions; initially all plantings were of southern form, ssp camaldulensis, but from mid-1960s northern form, ssp obtusa, became preferred for its faster growth and straighter stem; both of these subspecies present in Harare, most commonly the former; very large specimen in grounds of Claumond Flats at intersection of Natal Road and John Matetich Close, Avondale; largest specimen in Zimbabwe at Fairfield Park, near Mvuma; 46 m tall, 2.75 m in diameter, dimensions that are probably not exceeded in its native Australia. Subspecies simulata introduced into Zimbabwe in 1980s, planted only in research trials, Mtao Forest and Matabeleland.

EUCALYPTUS MANNENSIS Boomsma Mann Range mallee
Habit: large mallee or small tree to 10 m tall, 25 cm in diameter; crown broad, open or moderately dense.

Bark: rough over most or whole of stem(s), loose, flaky, grey to yellow-brown; upper stems and branches, particularly in large specimens, conspicuously smooth, white, grey, yellowish, or pale red-brown.

Adult leaves: petiolate, alternate, narrow to broadly lanceolate, 60-145 x 8-17 mm, tapering to fine point, concol- orous, glossy, green; venation not clearly visible, lateral veins numerous, at 40-50 degrees to midrib, intramarginal vein faint, slightly removed; reticulation very dense, numerous irregular oil glands.

Inflorescences: axillary, simple, 7-flowered; peduncles terete or angular, 3-13 mm long; buds subsessile to shortly pedicellate, 1-3 mm long, ovoid to broadly spindle-shaped or cigar-shaped, 6-9 x 3-5 mm, scar present; operculum conical; flowers white, April-October.

Fruits: pedicellate, hemispherical, 4-7 x 5-9 mm; rim thick; disc level, often covered with thin whitish skin; valves 3-4, usually 3, exserted, often with remains of style inserted in cleft at top; seed brown to grey-brown.
Derivation of names: botanical - refers to Mann Ranges in South Australia where first collected; common - refers to locality of first collection and to usual habit.
Taxonomy: Subgenus Symphyomyrtus.

Section Bisecta - cotyledons coarsely bisected or bilobed; leaves concolorous; buds and fruit large, thick.

Subsection Destitutae - pith of branchlets without glands.

Series Micrantherae - mallees or trees, leaf venation closely pinnate, oil glands numerous.

Subseries Bakerianae - bark rough; adult leaves narrow; MPA (essential oil 4-metyhyl-2-pentyl) absent.
Related species: subseries comprises 3 species, E. jutsonii, E. mannensis, and E. bakeri, all very closely related but not quite at supraspecies level; earlier draft of Brooker's classification indicated atypical subspecies of E. mannensis, subsp vespertina, but present status not known.
General: scattered and widespread on sandy plains and low dunes in arid areas of central Australia westwards into Western Australia; too small to be of any use except for fuelwood. Introduced into Zimbabwe in 1980s; planted experimentally as fuelwood species at Domboshawa Training Centre and elsewhere. Only typical subspecies present in Zimbabwe.

EUCALYPTUS BAKERI Maiden Baker's mallee
Habit: mallee or small crooked tree to 12 m tall, 65 cm in diameter.

Bark: rough, persistent to half stem height, grey-brown, compact, often tessellated; upper bark smooth, white, yellowish, or bluish green.

Adult leaves: petiolate, alternate, narrow-lanceolate, 75-90 x 7-10 mm, concolorous, glossy green or yellowish green, held somewhat erect, almost leathery, usually tapering to fine or hooked point; venation barely visible, numerous side veins at 35-45 degrees to midrib, intramarginal vein close to margin but distinct; reticulation dense, numerous oil glands.

Inflorescences: axillary, simple, 7-13-flowered, peduncles very short, 2-6 mm long, or to 15 mm, subterete; buds shortly pedicellate, elongated, 7-10 x 3-4 mm, scar present; operc-ulum conical or horn-shaped, much lighter brown than dark brown hypanthium; flowers creamy white, August-October.

Fruits: pedicellate, hemispherical or truncate-globose, 4 x 4 mm; rim thick; disc level to slightly ascending; valves usually 3, strongly exserted, style remnant inserted between halves of torn-away lobes; seed brown to grey brown.
Derivation of names: botanical - named after Richard Thomas Baker (1854-1941), economic botanist of Sydney Technological Museum (1888-1921), who did major research on Australian trees, especially eucalypts; common - from RT Baker and species growth habit.
Taxonomy: Subgenus Symphyomyrtus.

Section Bisecta - (see E. mannensis).

Subsection Destitutae - (see E. mannensis).

Series Micrantherae - (see E. mannensis).

Subseries Bakerianae - (see E. mannensis).
Related species: Subseries comprises 3 species, E. jutsonii, E. mannensis, and E. bakeri, all very closely related but not quite to supraspecies level.
General: very scattered range in southeastern Queensland and extreme north of New South Wales; of no commercial value.

Introduced into Zimbabwe in 1980s, principally to try for production of essential oils; planted on outskirts of Harare at St Marnock's Farm, Mount Hampden, also at Arcturus and near Marondera.

EUCALYPTUS SOCIALIS F. Muell, ex Miq. Red mallee
Habit: mallee, occasionally small tree up to 12 m tall.

Bark: rough, grey to grey-brown, over part of most stems, decorticating in long narrow ribbons over greater part of stems to leave smooth, white, or light grey surface; sub-fibrous at base of largest stems, somewhat scaly, persistent for short distance.

Adult leaves: petiolate, alternate, lanceolate, 80-110 x 12-20 mm, sometimes almost ovate, 50-75 x 25-38 mm, concolorous, green to grey-green, very firm texture; venation distinct, at 35-45 degrees to midrib; reticulation moderately dense, oil glands numerous.

Inflorescences: axillary, simple, 7-15-flowered; peduncles terete or angular, 5-23 mm long; pedicels 2-8 mm long; buds sometimes glaucous, 7-18 x 3-6 mm, scar present; hypanthium cup-shaped; operculum strongly beaked, rarely conical; flowers creamy-white to pale yellow, August-November.

Fruits: pedicellate, truncate-globose to slightly urn-shaped, tapering to pedicel, 5-10 x 5-8 mm; rim thin; disc depressed, valves 3-4, enclosed, apparently exserted due to persistent remnants of style; seed grey to dark grey-brown, smooth, shiny.
Derivation of names: botanical - from Latin socialis (sociable), referring to common occurrence with several other mallee species; common - not known, but probably from colour of wood.
Taxonomy: Subgenus Symphyomyrtus.

Section Bisecta - (see E. mannensis).

Subsection Destitutae - (see E. mannensis).

Series Subulatae - mallees or trees; bark rough or smooth; operculum beaked or rounded, narrower than hypanthium; valves of fruit enclosed, style remnants exserted.

Subseries Decussatae - seedling leaves decussate.
Related species: 9 species in subseries: E. eremicola,

E. sublucida, E. peeneri (very closely related);

E. yambarrana (somewhat isolated); E, socialis,

E. yalatensis, E. gillii, E. wyolensis (very closely related); E. aspersa (somewhat isolated).
General: widespread in mallee scrub of New South Wales, Victoria, and South Australia, in central Western Australia, southern Northern Territory, a few scattered occurrences in central Queensland; often on limestone rises; adapted to infertile calcareous soils in arid and semi-arid areas; oil producing species with relatively high cineole content; useful firewood; very good honey tree. Introduced into Zimbabwe in 1980s for trials as multipurpose species; planted at Dombo-shawa and other places.

EUCALYPTUS CINEREA F. Muell. ex Benth. Argyle apple
Habit: small to medium-sized forest tree with numerous branches; usually short crooked stem.

Bark: rough, persistent on trunk and larger branches, thick, fibrous, fairly soft, longitudinally furrowed, reddish brown to grey-brown.

Juvenile leaves: sessile, amplexicaul, opposite for many pairs, round to cordate, up to 80 x 55 mm, slightly discolorous, markedly glaucous.

Intermediate leaves : sessile to shortly petiolate, sometimes amplexicaul, subcordate to broadly ovate, 40-100 x 25-50 mm, only rarely non-glaucous.

Adult leaves: shortly petiolate, alternate to subopposite, broad-lanceolate, up to 110 x 20 mm, concolorous, glaucous; venation faint, at 30-45 degrees to midrib; moderately reticulate, oil glands present.

Inflorescences: axillary, simple, 3-flowered; peduncles 3-9 mm long; pedicels absent or very short; buds sessile or on very short pedicels, diamond-shaped, glaucous, 7-10 x 4-5 mm, scar present; operculum conical, about same width as length; flowers white, September-January.

Fruits: sessile or very shortly pedicellate, obconical, 5-8 x 5-9 mm; rim thick; disc level or ascending; valves 3-5, slightly exserted; seed grey-brown to black.
Derivation of names: botanical - from Latin cinus (ashes), referring to the glaucous leaves; common - thought to refer to area where species first found, and to apple-like appear- ance to early white settlers.
Taxonomy: Subgenus Symphyomyrtus.

Section Maidenaria - named in honour of JH Maiden - cotyledons bilobed; inflorescences axillary; adult leaves moderately reticulate, with oil glands both areolar (in centre of smallest unveined part of leaf) and intersectional (apparently at intersections of veinlets). Heterophylly common.

Subsection Euryota - juvenile leaves sessile, opposite for many pairs; style long; leaves with oil glands; disc and valves usually prominent; widespread distribution of species.

Series Argyrophyllae - bark rough throughout, longitudinally furrowed, remaining fibrous; juvenile leaves orbicular or ovate, entirely glaucous, commonly persistent in mature crown, buds in 3s or 7s, rhomboidal.

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