Eucalyptus effusa       0

Author: Murray Ian Hill Brooker (1934-2016)
Family: Myrtaceae Subfamily: Myrtoideae Tribe: Eucalypteae
Genus: Eucalyptus Subgenus: Symphyomyrtus Section: Bisectae Subsection: Glandulosae Serie: Contortae
English name: Shaggy-barked gimlet
Zone: Australia

Description
Its Latin epithet 'effusus' for spread oud, in reference to its growing habit in its natural area. This eucalyptus is endemic to Western Australia. It has a disjunct distribution near the Fraser Range between Norseman and Balladonia, to the north near Erayinia Hill and Cardunia Rock, near the transcontinental railroad and also southwest of Sandstone. It grows between hills and ridges in loamy clay soil. This Eucalyptus is found in semi-arid and arid regions with very draining and slightly alkaline soil. For a culture in temperate region, a maximum of sun is necessary for its good development. It tolerates moderate frosts and tolerates drought, but not excess water.
Eucalyptus effusa Observed in Australia by Thomas Mesaglio (license)
Botanical Description
It is a mallee or small tree with lignotuber. Its bark is rough, fine and gray in color. It is made up of persistent ribbons on the lower stems and sometimes extending to branches 5 to 10cm in diameter. The bark below is smooth, glossy gray-brown or red-brown or even coppery. The stems are rounded or square in cross section, glaucous or not.

The juvenile leaves are always petiolate, opposite for 5 nodes, then alternate. Widely lanceolate but quickly becoming falcate. They measure 5 to 11.5cm long and 0.7 to 4cm wide. Green to gray-green to slightly glaucous in color. The adult leaves are alternate, petiolate for 0.5 to 1.8cm long, linear and often curved. They measure 5 to 12cm long and 0.5 to 2cm wide. Base tapered to the petiole, entire margin and pointed apex. Gray-green, then green and glossy with maturing. The reticulation is sparse, the intra marginal vein is close to the margin.

The axillary inflorescence is simple, composed of 7 flowers per umbels often numerous towards the end of the branches. The peduncle is wider in its upper part. Mature buds are ovoid to almost cylindrical. They are 0.6 to 0.8cm long and 0.3 to 0.5cm wide. Scar present, operculum obtuse to strongly conical. The stamens are inflexed, the anthers oblong, versatile, sub-basifixed, dehiscent longitudinally. The style is long and straight, the stigma blunt to rounded. 3 or 4 locules. White flowers.

The fruit is pedicled over 0 to 0.2cm, cupular to obconical, it measures 0.4 to 0.6cm long and 0.4 to 0.7cm wide. 3 or 4 valves are present, exserted or near rim level. The seeds are brown and 1 to 2mm long, ovoid or flattened ovoid. Ventral hilum. They germinate very easily.
Member of
The Genus: Eucalyptus Subgenus: Symphyomyrtus Section: Bisectae Subsection: Glandulosae Serie: Contortae having the following characters: The buds have two opercula, the cotyledons are bisected and the branchlets have numerous oil glands in the pith. Within this subsection Eucalyptus effusa belongs to a small well known group, the gimlets (series Contortae), a group notable for the slender fluted, twisted shiny trunks. The gimlets are further recognised by very irregular island oil glands in the leaves and irregularly and deeply fissured seed-coats.
Useful plant
It is similar to Eucalyptus salubris and Eucalyptus campaspe but differs in its rough bark and fluted trunk.

References
- Encyclopedia of Australian Plants, Elliot W. Rodger & Jones David L. 2012 Vol. 4 pag. 85. ISBN
- Eucalypts of Australia. Eucalyptus effusa
- Six new taxa of Eucalyptus from Western Australia, Brooker, M. I. H. (Murray Ian Hill),. Nuytsia 1976 Vol. 2 pag. 103-117. Address
References for the genus
- Encyclopedia of Australian Plants, Elliot W. Rodger & Jones David L. 2012. ISBN
- Seeds of woody plants in the United States, Schopmeyer Clifford Scharff and others. 1974 pag. 384-392. Address
- A general history of the dichlamydeous plants, comprising complete descriptions of the different orders, Don, George. 1831 Vol. 2. Address
- A new classification of sections and series in Eucalyptus subg. Eudesmia (Myrtaceae), Bayly, Michael and Mclay, Todd and Cantrill, David and Fowler, Rachael. Muelleria: An Australian Journal of Botany 2023 Vol. 41 pag. 50-54. DOI
- A new series, Incognitae, of Eucalyptus L'Her., including a new species endemic to Fleurieu Peninsula and Kangaroo Island, South Australia, Nicolle, D. Journal of the Adelaide Botanic Garden 1995 pag. 73-78. JStor
- A new species and a new combination in the shining peppermint group of Eucalyptus and notes on the distribution of Eucalyptus willisii sens. strict, Rule, K. Muelleria: An Australian Journal of Botany 2008 Vol. 26. DOI
- A revision of the Yellow Bloodwoods (Myrtaceae: Eucalyptus ser. Naviculares Maiden), Brooker, M.I.H and Bean, Tony. Austrobaileya 1991 Vol. 3 pag. 409-437. DOI
- A taxonomic revision of Eucalyptus wandoo, E. redunca and allied species (Eucalyptus series Levispermae Maiden - Myrtaceae) in Western Australia, Brooker, M. I. H. (Murray Ian Hill), and Hopper, Stephen D. Nuytsia 1991 Vol. 8 pag. 1-189. Address
- Eucalyptus revelata, a rare new species related to E. mooreana (Myrtaceae) from the Kimberley region of Western Australia, Nicolle, Dean and Barrett, Russell L and others. Nuytsia 2018 Vol. 29 pag. 109-118. Address
- Eucalyptus wimmerensis revisited and notes on the morphologies and taxonomies of five Victorian mallee-boxes, Rule, K. Muelleria: An Australian Journal of Botany 2018 Vol. 37 pag. 39-64. DOI
- Five new endemic eucalypts for Victoria, Rule, K. Muelleria 2012 Vol. 30 pag. 83-105. DOI
- Four new species of Eucalyptus, S. T. Blake. Austrobaileya 1977 Vol. 1(1) pag. 1-9. JStor
- Four new species of ironbark (Eucalyptus L'Herit., Myrtaceae) from southern Queensland, Bean, Tony and M.I.H.Brooker,. Austrobaileya 1994 Vol. 4 pag. 187-194.
- Multivariate analysis of morphological variation in Eucalyptus series Psathyroxyla Blakely (Myrtaceae): taxonomic implications, Pfeil, BE and Henwood, MJ. Telopea 2004 Vol. 10(3) pag. 711-724. Address
- New subspecies in Eucalyptus caesia and in E. crucis (Myrtaceae) of Western Australia, Brooker, M. I. H. (Murray Ian Hill), and Hopper, S D. Nuytsia 1982 Vol. 4 pag. 113-128. Address
- New taxa and combinations in Eucalyptus and Angophora (Myrtaceae), Johnson, Lawrence and Hill, Kenneth. Telopea 1990 Vol. 4 pag. 37-108. DOI
- New taxa in Eucalyptus (Myrtaceae) for Victoria and notes on Victorian populations of Eucalyptus calycogona, Rule, K. Muelleria 2004 Vol. 20 pag. 9-32. DOI
- New taxa of Eucalyptus informal subgenus Symphyomyrtus (Myrtaceae), endemic to South Australia, Nicolle, Dean. Journal of the Adelaide Botanic Garden 2000 pag. 83-94. JStor
- Notes on Eucalyptus ser. Psathyroxyla Blakely (Myrtaceae) and other 'Ash group' eucalypts, Bean, Tony. Austrobaileya 1997 Vol. 5 pag. 125-135. DOI
- Notes on the narrow-leaved Ironbarks (Myrtaceae: Eucalyptus subseries Subglaucae), Bean, Tony. Austrobaileya 2005 Vol. 7 pag. 111-120. DOI
- Resolution of a 35-year taxonomic dilemma: Eucalyptus sp. Howes Swamp Creek (Myrtaceae) from eastern Wollemi National Park, New South Wales, Bell, Stephen and Phillips, Gavin and Nicolle, Dean. Telopea 2022 Vol. 25 pag. 151-163. DOI
- Six new infraspecific taxa in Eucalyptus (Myrtaceae) for Victoria, Rule, K. Muelleria 2011 Vol. 29 pag. 3-15. DOI
- Systematic studies in the eucalypts — 3 New taxa and combinations in Eucalyptus (Myrtaceae), Hill, Kenneth & Johnson, L. A. S. Telopea 1991 Vol. 4(2) pag. 223-267. Address
- Systematic studies in the eucalypts — 4 New taxa in Eucalyptus (Myrtaceae), K.D. Hill & L-A.S. Johnson. Telopea 1991 Vol. 4(2) pag. 312-349. Address
- Systematic studies in the Eucalypts 5. new taxa and combination in eucalyptus myrtaceae in western australia, Hill, K.D.; Johnson, L.A.S. Telopea 1992 Vol. 4(4) pag. 561-634. Address
- Systematic studies in the eucalypts. 10. New tropical and subtropical eucalypts from Australia and New Guinea (Eucalyptus, Myrtaceae), Hill, KD and Johnson, LAS. Telopea 2000 Vol. 8(4) pag. 503-539. Address
- Systematic studies in the eucalypts. 6. A revision of the coolibahs, Eucalyptus subgenus; Symphyomyrtus section; Adnataria series; Oliganthae subseries; Microthecosae (Myrtaceae), Hill, KD and Johnson, LAS. Telopea 1994 Vol. 5(4) pag. 743-771. Address
- Systematic studies in the eucalypts. 8. A review of the eudesmioid eucalypts, Eucalyptus subgenus Eudesmia (Myrtaceae), Hill, KD and Johnson, LAS. Telopea 1998 Vol. 7(4) pag. 375-414. Address
- Systematic studies in the Eucalypts. 9. A review of series Sociales (Eucalyptus subgenus Symphyomyrtus, Section Bisectaria, Myrtaceae), Hill, K.D. and Johnson, L.A.S. Telopea 1999 Vol. 8 (2) pag. 165-218. Address
- Taxonomic and nomenclatural notes on the Eastern grey boxes (Eucalyptus ser. Moluccanae Chippendale, Myrtaceae) and the reinstatement of Eucalyptus woollsiana R.T.Baker, Bean, Tony. Austrobaileya 2009 Vol. 8 pag. 25-34. DOI
- The Ironbarks Allied to Eucalyptus crebra F. Muell. and the Description of a New Species, E. quadricostata, in the Group, Brooker, M. Austrobaileya 1985 Vol. 2 pag. 148-152. DOI
- Three new Victorian species related to Eucalyptus aromaphloia L.D. Pryor and J.H. Willis and notes on the polymorphic nature of that species, Rule, K. Muelleria: An Australian Journal of Botany 1996 Vol. 9 pag. 133-143. DOI
- Two new mallee Eucalypts (Myrtaceae) from Gippsland, Victoria, Rule, K. and Molyneux, W.M. Muelleria 2011 Vol. 29 pag. 16-26. DOI
- Two new subspecific taxa within the Eucalyptus Series Argyrophyllae for Victoria, Rule, Kevin and Walsh, Neville. Muelleria: An Australian Journal of Botany 2017 Vol. 36 pag. 81-91. DOI
- Typification of some names in Eucalyptus (Myrtaceae), Part 1, Bean, Tony. Telopea 2009 Vol. 12 pag. 309-319. DOI
- Typification of some names in Eucalyptus (Myrtaceae), Part 2, Bean, Tony. Telopea 2010 Vol. 12 pag. 469-477. ResearchGate
- Typification of some names in Eucalyptus (Myrtaceae), Part 3, Bean, Tony. Telopea 2010 Vol. 12 pag. 511-520. ResearchGate
- Hommes et Plantes. Vol. 58 pag. 34-41. Address
- PlantÆxoticA. 2015 Vol. 28 pag. 18-26. Address
- PlantÆxoticA. 2015 Vol. 21 pag. 4-19. Address
- PlantÆxoticA. 2015 Vol. 11 pag. 7-11. Address
- Vegetative propagation of Eucalyptus through cuttings, Banthia K. M., Joshi C. M., Venkata Reddy P. B. & Sinha J. P. Indian Pulp & Paper Technical Association 1988 Vol. 25(1) pag. 37-40. Address
General specifications
Biological type: shrub
Frost resistance: 19ºF
Leaf color: dark green
Flower color: white
No transplantation: Yes
Reproduction mode: hermaphrodite plant whoes flowers produce both male and female gametes
IUCN Red List of threatened species status: Least Concern

Specifications for the Mediterranean basin
Adult size (h x w): 13,1ft x 6,5ft
Sun exposure: full sun (Sun hours: >6h
Foliage: evergreen
Growth: fast
Flowering time from April until July

Specific information for our garden
Planting substrate: 30%Compost+30%Coco+40%Sand
Plant watering: 1x a week pH 5.5
Logical sequence of containers for: Eucalyptus; forestry plate, forestry pot 3L, Airpot 12L, Airpot 50L, Airpot 800L
Propagation is done by cuttings

Ecology in its country of origin
Rainfall: 100-300mm
Gravelly soil: much
Clay soil: much
Sandy soil: much
Limestone soil: a little
Acidic soil: much
Draining soil: much
Sowing instructions
SPRING Select the largest and most fleshy BROWN seeds. Sow the seeds at 2mm depth in the Well Drained Seed Sowing Mix between 64-72°F. During germination keep the substrate moist and in daylight. The seeds germinate in 3-6 weeks. The viability of the seeds, kept under good conditions, is 10 years.
The average seed weight is 401,6 per gram (0,00249g).

Germination references for the genus
- Seeds of woody plants in the United States, Schopmeyer Clifford Scharff and others. 1974 pag. 384-392. Address
- Eucalypt seed and sowing. Native Forest Silviculture Technical Bulletin 2010 Vol. 1. Address
- USDA Forest Service's Woody Plant Seed Manual, John K. Francis and Craig D.Whitesell. 2008. Address

Experiences in the garden
14-02-19A Obtaining seeds from seed provider Nindethana Seeds collected in '....'. (Cultivated from unknown origin)
03-03-20 Send a batch to nursery Railhet.
04-03-20 Sown 60 seeds in a seed plate F, they did not geminate in Serre3.
Protocol: Spring 2mm Sowing mix+Sand 59-68°F Damp substrate+Light 3-6w
10-03-21 Sown 30 seeds in a seed plate F, they did not geminate in Serre3.
Protocol: Spring Brown Seed 2mm Sowing mix+Sand 59-68°F Damp substrate+Light 3-6w
10-05-22 Sown 30 seeds in a seed plate F, they did not geminate in Serre3.
Protocol: Spring Brown Seed 2mm Sowing mix+Sand 68-77°F Damp substrate+Light 3w