Bottle tree…..Brachychiton rupestris

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Brachychiton rupestris

The Queensland Bottle Tree (Brachychiton rupestris) originally classified in the family Sterculiaceae, which is now within Malvaceae, is native of Queensland, Australia. Its grossly swollen trunk gives it a remarkable appearance and gives rise to the name. As a succulent, drought-deciduous tree, it is tolerant of a range of various soils, and temperatures.

It can grow to 18–20 meters (59–66 ft) in height and its trunk has the unique shape of a bottle. Its swollen trunk is primarily used for water storage. On every tree the leaves are variable from narrow and elliptic to deeply divided. Clusters of yellowy bell shaped flowers are hidden within the foliage, and are followed by woody boat-shaped fruits

Queensland Bottle tree
Scientific classification
Kingdom: Plantae
(unranked): Angiosperms
(unranked): Eudicots
(unranked): Rosids
Order: Malvales
Family: Malvaceae
Genus: Brachychiton
Species: B. rupestris
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Paraserianthes lophantha..Australian Silk Tree

Paraserianthes lophantha

From Wikipedia, the free encyclopedia
Paraserianthes lophantha
Scientific classification
Kingdom: Plantae
(unranked): Angiosperms
(unranked): Eudicots
(unranked): Rosids
Order: Fabales
Family: Fabaceae
Subfamily: Mimosoideae
Genus: Paraserianthes
Species: P. lophantha
Binomial name
Paraserianthes lophantha
(Willd.I. C. Nielson
Albizia lophantha

Paraserianthes lophantha, commonly called AlbiziaCape Leeuwin Wattle or Crested Wattle, is a fast-growing tree that occurs naturally along the southwest coast of Western Australia, from Fremantle to King George Sound.[1] It was first spread beyond southwest Australia by Baron Ferdinand von Mueller, who gave packets of P. lophantha seeds to early explorers under the assumption that if they planted the seeds at their campsites, the trees would indicate the routes they travelled.[2]

It is considered a weed in Australia, South Africa, the Canary Islands, and Chile.


Seed pods

[edit]Further reading

  • Randall, Roderick Peter (2002). A Global Compendium of WeedsMelbourne: R. G. & F. J. Richardson. ISBN 0958743983.
  • Blood, Kate (2001). Environmental Weeds: A Field Guide for SE Australia. Mount Waverley, Victoria: C. H. Jerram & Associates.ISBN 0957908601.
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Albizia..Persian Silk Tree

For the Australian tree commonly named “Albizia”, see Paraserianthes lophantha.
Persian Silk Tree (Albizia julibrissin),
foliage and blossoms
Scientific classification
Kingdom: Plantae
(unranked): Angiosperms
(unranked): Eudicots
(unranked): Rosids
Order: Fabales
Family: Fabaceae
Subfamily: Mimosoideae
Tribe: Ingeae
Genus: Albizia
Durazz., 1772
About 150 species, see List of Albizia species
Albizzia Benth.

Albizia is a genus of about 150 species of mostly fast-growing subtropical and tropical trees and shrubs in the subfamily Mimosoideaeof the legume family, Fabaceae. The genus is pantropical, occurring in AsiaAfricaMadagascarCentralSouth, and southern North America and Australia, but mostly in the Old World tropics. Some species are considered weedy.

They are commonly called silk plant or sirises. Peculiarly, the obsolete form of spelling the generic name – with double ‘z’ – has stuck, so that another commonly used term is albizzias(though the form albizias is also found, particularly in species that are not widely known under a common name). The generic name refers to the Italian nobleman Filippo degli Albizzi, who in the mid-18th century introduced siris to Europe.

These are usually small trees or shrubs with a short lifespan – though the famous Samán del Guère near Maracay in Venezuela is a huge Albizia saman specimen and several hundred years old. The leaves are pinnately or bipinnately compound. Their small flowers are in bundles, with showy stamens much longer than the petals. Confusingly, some species are given the name “mimosa” which correctly belongs to species in the related genus Mimosa. Unlike those of MimosaAlbizia flowers have much more than 10 stamens. Albizia can also be told apart from another large related genus, Acacia, since its flowers have their stamens joined at the base whereas in Acacia stamens are free (separated).[1]

Persian Silk Tree or Pink Siris (Albizia julibrissin) extends well north into temperate regions in East Asia and is by far the cold-hardiest species. It tolerates temperatures down to about −30 °C (−22 °F), provided it gets adequate summer heat to ripen the shoots. In North America it is commonly grown as an ornamental tree, but has become naturalized in severalUS states, and is regarded as an invasive species.

Albizia species are used as food plants by the larvae of some moths of the genus Endoclita inclulding E. damorE. malabaricus and E. sericeus.




Numerous species placed in Albizia by early authors were eventually moved to other genera, most notably Archidendron. Other genera of Ingeae (AbaremaArchidendropsis,Balizia[disambiguation needed]BlanchetiodendronCalliandraCathormionEnterolobiumHavardia,HesperalbiziaHydrochoreaPararchidendronParaserianthesPseudosamanea and Serianthes) have also received their share of supposed Albizia species, as have the Mimoseae Newtonia andSchleinitzia, and Acacia[verification needed] from the Acacieae. Some presumed “silk trees” are in fact misidentified members of the not very closely related Erythrophleum from the Caesalpinioideae and the Faboideae Lebeckia.[2]

The delimitation of Falcataria and Pithecellobium, close relatives of Albizia, is notoriously complex, with species having been moved between the genera time and again, and probably will continue to do so. These include for example Falcataria moluccana (Moluccan Albizia, formerly Albizia moluccana), a common shade tree on tea plantations. Other closely related genera like Chloroleucon and Samanea are often merged withAlbizia entirely.[2]

[edit]Invasive Species

Molucca albizia (Falcataria moluccana) and Chinese albizia (Albizia chinensis) are considered invasive species in Hawaii and on many Pacific Islands.[3] The tree grows very rapidly and can quickly colonize disturbed areas in wet environments. The tree is prone to shedding large branches, which have been responsible for damaging power lines, houses, and other infrastructure in Hawaii.

[edit]See also

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Mimosa or Silk Tree

Albizzia julibrissin – Mimosa or Silk Tree

Family – Leguminosae


Size 25 to 30 feet in height, spread at least equal to or greater than height. Broad spreading with a rounded, mushroomed crown. Growth rate is fast, 3 feet or more per year is not unusual.

Foliage Alternate, bipinnately compound, up to 20″ long with numerous pinnae, each having 40 to 60 small leaflets. Very fine textured and tropical in appearance.

Flower Flowers are unusually attractive and slightly fragrant. They have numerous fiber optics like, 1″ to 1 1/2″ long stamens that merge from white to a violet-pink that make the flower appear brush-like. Flowering is profuse in late May and June and occurs sporadically on various trees throughout July and August.

Pests and Diseases - A vascular wilt disease has been particularly destructive on many Mimosa throughout the south. This usually ends up killing the tree to the ground and then it resprouts back with numerous suckers. I have seen many trees killed by this disease, while others seem to persist on unaffected.

Landscape Use - Not a whole lot due to potential disease problems. In the south one shouldn’t have to plant Mimosa, just create a ‘waste area’ in your yard as they seed prolifically and should colonize it in a short time. People have a affinity for this tree..

At Lawn Hill Station the property surrounding the homestead is lined with these huge shady trees that look very beautiful.

Birds love the nectar in the flowers, and honey eaters are always there among the blossoms in Spring.

Performance – 2 It does have a attractive flower and fairly nice foliage, but it just doesn’t have a whole lot of potential for the long term. Hardy in to zone 6, but will likely be killed back or damaged during winters north of this zone.

….but here in North Queensland, the tree grows well, tall, hardy and sturdy.

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Coolibah…Eucalyptus Microtheca

Photos taken October 2011 at Lawn Hill


Tree to 10 m tall, rarely more, or sometimes a mallee. Forming a lignotuber.
Bark rough, whitish grey to dark grey, box-type, often deeply fissured, coarsely flaky or becoming tessellated, the branches commonly rough-barked though this feature is variable.
Branchlets lacking oil glands in the pith; usually non-glaucous, rarely glaucous.
Juvenile growth (coppice or field seedlings to 50 cm): stems rounded to square in cross-section, usually non-glaucous; juvenile leaves always petiolate, opposite for a variable number of nodes then alternate, narrowly lanceolate, 5–15 cm long, (0.3)0.5–2.5 cm wide, apex rounded or pointed, bluish green to green.
Adult leaves alternate, petioles 0.6–2 cm long; blade lanceolate to falcate, 5–19.5 cm long, 0.6–3(4.5) cm wide, base tapering to petiole, apex pointed or rounded, margin entire, concolorous, dull, green to blue-green or rarely glaucous, side-veins acute or at a wider angle to the mid-rib, reticulation very dense, intramarginal vein present, oil glands sparse, intersectional.
Inflorescences terminal, peduncles slender, 0.2–0.9(1.2) cm long; buds in 7s but umbels are sometimes irregular due to short internode elongation within the cluster, pedicels 0.1–0.3 cm long. Mature buds pyriform to obovoid or globular, 0.3–0.4 cm long, 0.2–0.3 cm wide, non-glaucous or glaucous, scar present (outer operculum lost early), operculum rounded and apiculate, rarely conical, stamens irregularly flexed, all fertile, anthers adnate, cuboid, dehiscing by lateral slits, style long, straight, stigma blunt, locules 3 or 4, the placentae each with 4 vertical ovule rows. Flowers white.
Fruit on pedicel 0.1–0.3 cm long or, rarely, subsessile, truncate-globose to obconical, usually contracted at the top, 0.2–0.4 cm long, 0.3–0.7 cm wide, glaucous or non-glaucous, rim narrow, rarely flared, disc descending vertically, narrow, valves 3 or 4, near rim level or barely exserted.
Seeds dark brown, 1–2 mm long, flattened-ovoid, dorsal surface smooth, hilum ventral.

Cultivated seedling (measured at ca node 10): cotyledons reniform; stems rounded or square in cross-section; leaves always petiolate, opposite for ca 4 to 10 nodes then becoming alternate, lanceolate to narrowly so, 6–10.5 cm long, 0.5–1.5 cm wide, base tapering, apex rounded or pointed, blue-green to grey-green or green.


A tree of widespread distribution in northern Australia, found fringing seasonally dry watercourses, swamps, lakes and low-lying areas subject to temporary inundation. It occurs east from the Ord River in the Kimberley region of Western Australia through the Northern Territory north from about Newcastle Waters and including the Barkley Tableland (but see below), to the Roper River and Macarthur River, extending into the Gulf country of Queensland as far east as western Cape York and as far south as near Mount Isa and Chillagoe.Eucalyptus microtheca  usually has rough bark over the whole trunk extending to the branches and a crown of dull green, grey-green or sometimes glaucous leaves and small fragile fruit with valves at rim level when dehisced.

Eucalyptus microtheca is most closely related to the widespread E. coolabah which is found in similar but drier habitats to the south and south-east, and to E. victrix which occurs in still drier habitats from central Australia west to the Pilbara. E. coolabah has rough bark on part or all of the trunk, having whitish smooth bark on the branches, and has conspicuously exserted valves in the otherwise shallower hemispherical-obconical fruit. E. victrix  has smooth powdery white bark and similar fruit to E. microtheca with valves at rim level or slightly exserted. It is also closely related to E. tectifica, both species having rough bark to the small branches. E. tectifica and E. microtheca are separated by the shape and dimensions of their juvenile leaves, E. microtheca usually being narrowly lanceolate and  E. tectifica normally ovate to broadly lanceolate. The fruit of E. tectifica also tend to be slightly wider than those of E. microtheca but some overlap in dimensions does occur. Another closely related member of this group is E. acroleuca from Cape York Peninsula. It differs by having basal rough bark with a fairly regular “cut-off” about halfway up the trunk and conspicuous smooth bark on the upper trunk and branches, and very small fruit (0.2–0.3 cm wide only) with enclosed valves.

Several localized forms of species in this group have been described – E. cyanoclada, a blue-leaved more or less glaucous form occurring around Lake Woods and Newcastle Waters in the Northern Territory; E. barklyensis with smooth smaller branches, thicker leaves and more spreading form than E. microtheca, restricted to the Barkly Tableland in the Northern Territory; and E. helenae, described from the south-western Barkly Tableland, differing in having marginally larger fruit with flared top a broader disc, smooth branches and thicker and sometimes wider leaves than E. microtheca. In EUCLID we take a broader view of E. microtheca, including E. cyanoclada, E. barklyensis, E. helenae  within it. The taxonomy of the group is complicated by E. microtheca, E. coolabah and E. victrix having adjoining distributions and showing intergradation in form. To make reliable identification collectors will need to note the extent of rough bark and ensure collection of mature fruit. Eucalyptus microtheca and related species flower in late spring and early summer, quickly ripen their fruit and shed seed over the following few months. The fruit are on slender pedicels and peduncles and are soon lost from the trees. Even with mature fruit and the most careful observation of bark and leaves there will still be many individuals, especially on the Barkly Tableland, that don’t fit neatly into any particular coolibah species. Populations of coolibahs may contain individuals all of which display distally contracted fruit (like E. microtheca, E. barklyensis and E. helenae) but which vary in bark persistence, from having some scrappy basal rough bark with the upper trunk and branches being smooth-barked, to being fully rough-barked to the smaller branches, and with all possibilities in between. Because of the variability in bark persistence and the seeming consistency of “microtheca-like” fruit shape we have chosen to synonymize E. barklyensis and E. helenae with E. microtheca rather than E. coolabah. However it would not surprise us if there were coolibah trees in this area that matched E. coolabah in fruit shape just to complicate the picture.

Eucalyptus microtheca belongs in Eucalyptus subgenus Symphyomyrtus section Adnataria (the boxes) because the buds have two opercula, ovules are in four rows, seeds are flattened-ovoid, cotyledons are reniform, and anthers are rigid on the staminal filaments. Within section Adnataria, E. microtheca is part of a subgroup of box species with mostly tropical distribution, series Aquilonares subseries Protrusae, having inflorescences terminal on the branchlets, adult leaves very densely reticulate and fruit that are small, fragile and have exserted valves.

Flowering Time

Flowering has been recorded in September, November, December and January.

Origin of Name

Eucalyptus microtheca: from Greek, micros, meaning small, and thece, a box, referring to the small fruit.

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Pith of the Eucalyptus and Brief History



Once a specimen has been taken, a very handy and accessible feature is the pith of the branchlets. In the southern half of the country about half of the dry country mallees have a line of clear-coloured or brown oil glands in the pith usually visible to the naked eye, while the remaining species have a white or uniformly coloured, undifferentiated pith. This character is easily assessed in the field by pulling a side branchlet away from the main axis. Pith glands, if present, will be most conspicuous at the nodes so this is where the character should be sought for its presence or absence. The developmental origin of these discrete rounded pith glands is unknown.

Pith gland absence or presence is a character of moderately high, not absolute, reliability and is a particularly useful character to help identify South Australian and southern Western Australian species.

This, however, is not true in all areas of the country. Many, perhaps all, species of Corymbia (bloodwoods and ghost gums) and Angophora have obvious short or elongated duct-like spaces in the pith of the branchlets. These are not as easily seen in the field as the discrete round pith glands but can be seen with a 10X lens, especially at or near the leaf bases. These ducts may be filled with a sticky brown substance (?oil or resin) or the contents may be crystalline but they are not round pith oil glands as described above. Only one species of ghost gum, C. kombolgiensis has been observed with discrete round brown pith oil glands. In EUCLID we have scored this character when we have seen it in Corymbia and Angophora species, however when identifying these species it should be used with caution or avoided.

A brief history of Eucalyptus, Angophora and Corymbia

Although eucalypts must have been seen by the very early European explorers and collectors, no botanical collections of them are known to have been made until 1770 when Joseph Banks and Daniel Solander arrived at Botany Bay with James Cook. There they collected specimens of C. gummifera and later, near the Endeavour River in northern Queensland, they collected E. platyphylla; neither of these species was named as such at the time.

In 1777, on Cook’s third expedition, the botanist David Nelson collected a eucalypt on Bruny Island, southern Tasmania. This specimen was taken to the British Museum in London, where it was named Eucalyptus obliqua by the French botanist, Charles-Louis L’Héritier de Brutelle, who was working in London at the time. He coined the generic name from the Greek roots eu and calyptos, meaning ‘well’ and ‘covered’, in reference to the operculum of the flower bud. This organ protects the reproductive structures during their development and sheds under pressure from the emerging stamens at flowering. The name obliqua was derived from the Latin, obliquus, meaning ‘oblique’, describing a leaf base where the two sides of the leaf blade are of unequal length and do not meet the petiole at the same point.

In the publication of Eucalyptus obliqua, L’Héritier recognized in the generic name a feature common to all eucalypts – the operculum. In his choice of specific name, he recognized not only a characteristic feature of E. obliqua but one that occurs in most other eucalypts as well. E. obliqua was published in 1788 and coincides with the date of the first official settlement of Australia.

Between 1788 and the beginning of the nineteenth century several more species of Eucalyptus were named and published. Most of these were by the English botanist James Edward Smith and most were, as might be expected, trees of the Sydney region. They include the economically valuable E. pilularis, E. saligna and E. tereticornis, each of which also occurs in Queensland, with the distribution of E. tereticornis extending to the island of New Guinea.

Also in this period the genus Angophora was published, in 1797, by the Spanish botanist Antonio Jose Cavanilles, based on specimens collected at Port Jackson by Frenchman Luis Née in 1793. Née was botanist with the Alejandro Malaspina expedition. Various authors have considered Angophora to be sufficiently distinctive that it should be maintained as a separate genus. Others believe it is a ‘eucalypt’. We recognize both Eucalyptus and Angophora in EUCLID, reflecting results of recent research and usage by the general community.

The nineteenth century was a period of extensive land exploration. This resulted in the discovery of many new eucalypts and their subsequent naming by several of the great botanists in Australian history, particularly Ferdinand von Mueller, whose work on eucalypts contributed greatly to the first comprehensive account of the genus in George Bentham’s Flora Australiensis (1867). Bentham never visited Australia, but his account is the most important early systematic treatment of the genus Eucalyptus.

Some earlier authors had constructed classifications, but the distinctions they used – for example, shape of the operculum and the juvenile leaf arrangement – were only applicable to far fewer species than were known to Bentham; they were of little use when applied to a much larger number of species. One useful study before that of Bentham, however, was Mueller’s description of different bark types (Mueller, 1858). These still have relevance in distinguishing between, for example, groups that shed or retain dead bark and, in the latter case, between ironbark and other types of rough bark.

Bentham divided the genus into five series whose distinctions were based on characteristics of the stamens, particularly the anthers. Categories within each series were based largely on the leaves, and on bud and fruit shape. He was obviously working with limited botanical specimens, and field characters were not available to him unless communicated by others from Australia.

Mueller, working in Australia, devised another classification based on the anthers (Mueller, 1879-84), while Joseph Henry Maiden (1924) elaborated on the anther system, which was taken even further by William Faris Blakely (1934). By this time, classification based on the anther system had become too complex to be workable.

Other more consistent characters have been sought in recent years to aid in the construction of classifications. Of these, leaf venation, the nature of bristle glands, the morphology of the seeds, nature of the operculum and the structure of the inflorescence are fundamental. More sophisticated equipment has usually enabled the examination of these leaf and floral structures early in and during their development. Similarities thus recognised usually provide the evidence of natural affinity between species and groups of species. In other words, botanists became better equipped to decide whether these similarities noticed in different species and groups were the results of inheritance from a common ancestor or if they had independently evolved, in many cases as an adaptive necessity such as lignotuber formation or salt tolerance.

A comprehensive but informal classification of all known eucalypt species was published in 1971 by the late L.D. Pryor and L.A.S. Johnson. It comprised seven major groups based on the association of many morphological characters and suggested by the breeding incompatibility between them. Their system has been subjected to close scrutiny in the past 30 years. Many improvements to this classification were proposed by Johnson himself and by others, although he never formally published a system of classification.

Briggs and Johnson (1979) contributed a major advance in the botany of the whole family Myrtaceae, in which they outlined for the first time a comprehensive analysis of inflorescence structure in all genera and its indication of evolutionary trend.

In Volume 19 of the ‘Flora of Australia’, all eucalypts published to 1988, were comprehensively treated (Chippendale, 1988). This work includes 513 species of Eucalyptus arranged in 92 series, many of which were published formally in this volume. This is not a structured classification as there are no subgenera or sections. The work is of particular value for its typology and erection of many new taxonomic series.

The decade after 1988 saw the application of advanced methodology in the study of the genus Eucalyptus, especially in phylogenetic analyses of taxonomic series (e.g. Ladiges et al., 1987; Hill and Johnson, 1995) and in the use of molecular techniques in the estimation of infra-generic relationships within the genus and between cognate genera (Ladiges et al., 1995; Ladiges and Udovicic, 2000).

Most notably in 1995 K.D. Hill & L.A.S. Johnson published a monograph on the bloodwoods and ghost gums in which they described the genus Corymbia, with species grouped in seven sections which intentionally follow from the earlier work of Pryor & Johnson (1971). This grouping at section, and at series and subseries rank is, according to the authors, intentionally informal, i.e. outside the International Code of Botanical Nomenclature (Hill & Johnson, 1995, p. 186)

In 2000, M.I.H. Brooker published a formal classification of the genus, which is a synthesis in the form of an updated taxonomy to accommodate the numerous taxa published since Chippendale’s 1988 treatment. While based conceptually on the work of Pryor & Johnson, it recognizes one genus, Eucalyptus and includes Angophora and Corymbia as 2 of a total of 13 subgenera, and assigns all species known to the year 2000 to a heirarchical system of subgenera, sections, subsections, series, subseries and supraspecies (Brooker 2000).

The 5 years following Brooker’s 2000 classification has seen further systematic and phylogenetic investigations of the eucalypts. Increasingly, molecular data are incorporated into studies of the relationships between the subgenera recognised by Brooker, and this is reflected in ongoing refinements to eucalypt systematics. The various concepts proposed from those studies are discussed in the accompanying section “Evolutionary Relationships in Eucalyptus sens. lat.”.

Evolutionary Relationships in Eucalyptus sens. lat.



Whilst hybridism has been frequently reported between species in Corymbia, and also between species from within the same subgenus of Eucalyptus, rarely are hybrids between species from different subgenera of Eucalyptus seen in the field. An example of the latter is hybrids between E. cloeziana (subgenus Idiogenes) and E. acmenoides (subgenus Eucalyptus) (see Stokoe et al., 2001). Manipulated hybrids between species from different subgenera have never been successful.

Hybridism requires genetic compatibility and synchronous flowering times (unless manipulated). Hybrids between species within a subgenus are rare in natural forests or scrubs. They are more likely to be seen as regrowth trees or mallees in disturbed areas where changed environmental conditions may be more amenable to the success of the hybrid combination. Hybrids in stands appear to be selected against in favour of the parent species.

Many reported hybrids are better interpreted as natural intergrades between closely related species. e.g. E. burgessiana and E. stricta in eastern New South Wales, E. dalrympleana subsp. dalrympleana and E. viminalis subsp. viminalis in Tasmania, E. angulosa and E. incrassata in coastal South Australia and Western Australia, E. brownii and E. populnea in Queensland.

Hybrids can complicate the identification of specimens and there are a couple of ways of investigating more closely whether the problem specimen is a hybrid. Firstly, close observation of the features of eucalypts in the stand where you collect the specimen may indicate that some trees appear intermediate in some features such as bark type or crown colour. Secondly if there is seed on your specimen you may be able to raise a moderately large number of seedlings (say 10-20) and look for gross variation in seedling leaf shape and other characteristics, and compare these with similarly grown seedlings raised from individuals of the purported parents. This is of course a lengthy business but can give good information.

There are a few well-known formally named hybrids where both parents have been identified and are seen in the field, e.g.

E. brachyphylla (E. kruseana × E. loxophleba subsp. lissophloia)
E. erythrandra (E. incrassata or E. angulosa × E. tetraptera)
E. missilis (E. cornuta × E. angulosa)
and possibly E. balanites (E. lanepoolei × E. decipiens).

In another example, E. annuliformis, only one parent is evident, E. drummondii, the other being a mystery.

Many presumed hybrids have been formally named by botanists of the eucalypts over the last 200 years. The most recent annotated list of many of these names can be found in Chippendale (1988, pp. 428–442). Hill & Johnson (1995) list, in an appendix, hybrids and intergrades they have observed in Corymbia.

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Seeds of the Eucalyptus


One useful feature that is not immediately available in the field is the seeds. Until the vascular connections between the individual fruits held in the crown and the parent tree are broken, the valves will not open. Otherwise, eucalypt fruit are held on the branchlets often for years. Seed from detached fruits, however, can be ready for inspection after about 24 hours by placing unopened fruits in a paper bag where they dry out quickly and shed the seeds and the thinner chaff particles. There is a great number of seed forms and these can be seen either with the naked eye or with a lens. Fortunately, related species have identical seeds and the character is therefore one of high reliability. Because words do not adequately convey the actual seed shape for most species, experience is needed to educate the user who will ultimately find the seeds to be an invaluable aid in discriminating species and groups of related species. We suggest the following terms as a guide.

Seed shape: flattened or saucer-shaped Flattened or saucer-shaped
The seed is somewhat flattened with a distinct upper (dorsal) and lower (ventral) side. The ventral side may be somewhat concave, with the hilum in the centre. Angophora and the ghost gums have this type of seed.
Seed shape: pyramidal or obliquely pyramidal Pyramidal or obliquely pyramidal
The seed is pyramid shaped with a relatively smooth or lacunose, flat or rounded dorsal side. The ventral side is usually ribbed, wrinkled or angled and is surmounted by a narrowed face at the summit where the hilum is (e.g. E. acmenoides). This is the seed type in most of the monocalypts although there is a great amount of variety in their seed form. Perhaps the most extreme seed shape in the monocalypts is seen in some western endemics, e.g. E. buprestium and E. todtiana, in which the body of the seed is small in comparison to the grossly extended curved lateral wings.
Seed shape: boat-shaped Boat-shaped
The seed is elongated and strongly keeled dorsally with a large, conspicuous hilum in the middle of the flat underside. The edges may be flanged or narrowly winged. C. gummifera and C. calophylla notably have this type of seed.
Seed shape: cuboid Cuboid
The seed is chunky, often with a smooth, shiny or somewhat granular, sometimes slightly rounded, dorsal side. The hilum is situated on a smaller terminal face separated from the dorsal side by the side walls of the seed. These walls are often angular. The chaff is usually similar to the seed, but somewhat smaller and lighter coloured (e.g. E. seeana).
Seed shape: ellipsoidal with terminal wing Ellipsoidal with terminal wing
The flattened-ellipsoidal body of the seed occurs at the lower end (considering the disposition of the ovule on the placenta in the intact bud), with a transparent wing as long as the body of the seed at the top end. The wings may be seen, just before seed shed, emerging from the top of the ovary. The hilum is usually positioned near one edge not far from the start of the wing. The wing is purely a descriptive morphological term and the structure has no apparent aerial function. Most of the bloodwoods have this type of seed (e.g. C. chippendalei).
Seed shape: pointed at one end Pointed at one end
The seed is somewhat flattened, usually rounded at one end and pointed at the other. It may be described as teardrop-shaped (e.g. E. conica).
Seed shape: d-shaped D-shaped
The seed is roughly disc-like with a short straight side and a longer connecting curved side. The hilum is towards the narrowed end (e.g. E. porosa).
Seed shape: spherical Spherical
The seed is more or less spherical (e.g. E. desmondensis).
Seed shape: ovoid or depressed ovoid Ovoid or depressed-ovoid
The seed is ovoid or elliptical in outline but flattened with the hilum on the more or less concave ventral side (e.g. E. aggregata). A large number of species have this type of seed. Examples are the section Maidenaria, endemic to eastern Australia, in which the dorsal surface is often lacunose, and a large number of mallees occurring across southern Australia. These seeds have very smooth dorsal sides with two or three shallow longitudinal grooves. This is seen particularly in series Subulatae and Calycogonae.
Seed shape: obliquely elongated Obliquely elongated
The seed is like a narrowly drawn-out pyramid with the dorsal face curved and prolonged into a thin ‘tongue’. The terminal face is small, flat and oblique on the seed with the hilum in the middle. The sides are ridged (e.g. E. burracoppinensis).
Seed shape: linear Linear
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