CONTACT : WHISNU FEBRY AFRIANTO whisnuafrianto@apps.ipb.ac.id

Abstract
Acacia deccurens Wild. has been reported as invasive alien species (IAS) in
several areas of Indonesia. Climate change may impact IAS to be more invader.
The study aimed was to develop a species distribution model of A. deccurens to
depict the potential distribution under climate change in Indonesia. Biodiversity
and Climate Change Virtual Laboratory (BCCVL) was used to examine a species
distribution model (SDM) of A. decurrens in Indonesia based on climate variables
and its naturalized distribution to predict the project distribution under current
and future climate conditions. The data was collected from Global Biodiversity
Information Facility (GBIF) to identify the species occurrences. The climate
variables used in this study were temperature and precipitation layers based on
WorldClim, current climate (1950-2000), 2.5 arcmin (~5km). The SDM of the
Generalized Linear Model (GLM) was utilized to predict the response variable as
a function of multiple predictor variables. We selected four IPCC Representative
Concentration Pathways (RCP) 2.6, 4.5, 6.0, and 8.5 for 2050. The prediction of
the distribution of A. deccurens in 2050 showed that it was likely to decrease in
Indonesia (mostly found only in Sumatra and Sulawesi Island). Almost all climate
variables used in this study were responsive to A. decurrens distribution, except
B09 - mean temperature of the driest quarter. The ROC plot showed excellent
values (0.99). The information of the potential distribution on IAS under current
and future climate scenarios can be used for policymakers and stakeholders to
manage and handle the invasion.

ISSN : 2580-2410
eISSN : 2580-2119

The Potential Distribution Prediction of The Invasive Alien
Species Acacia decurrens Wild., in Indonesia

Whisnu Febry Afrianto 1*

1 Ecosystem and Biodiversity (Ecosbio), Jl. Merapi 02/01, Datengan, Grogol, Kediri, 64151

Introduction

The genus of Acacia worldwide includes ± 1300 species and about 960 species come
from Australia and it spreads in the tropics to the temperate area, namely Europe, Africa,
South Asia, and America (Wrigley & Fagg, 2013). One of the Acacia species spread in
Indonesia is Acacia deccurens Wild. This species, commonly known as black wattle or green
wattle, is a fast-growing tree species of the Fabaceae family (Bamidele et al., 2017). This
species can grow about 6-12 m and easily adapt to acidic soil conditions (Endalew et al.,
2014). Naturally, A. deccurens grows in a lower mountain valley (Molla & Linger, 2017).

A. deccurens is widely planted because it has benefits both for economic and
environmental in forestry, agricultural, and ecosystem forestry (Nigussie et al., 2016;
Wondie & Mekuria, 2018; Nigussie et al., 2020; Chanie & Abewa, 2021; Nigussie et al.,

OPEN ACCESS International Journal of Applied Biology

Keyword
Acacia deccurens,
climate change, invasive
alien species, special
distribution model.

Article History
Received 12 September 2021
Accepted 30 December 2021

International Journal of Applied Biology is licensed under a
Creative Commons Attribution 4.0 International License, which
permits unrestricted use, distribution, and reproduction in any
medium, provided the original work is properly cited.

International Journal of Applied Biology, 5(2), 2021

2021). Several studies have reported that A. deccurens cultivated in degraded land can
improve soil fertility, increase water quality, and prevent soil erosion (Reubens et al., 2011;
Molla & Linger, 2017; Bazie et al., 2020). Furthermore, according to CABI (2021), A.
decurrens can be used as fuels (charcoal and fuelwood), ornamental plants, and materials
(tanning and timber) (Richardson et al., 2015).

On the other side, several publications have reported that A. decurrens is a severe
invasive problem (i.e., Hawai, New Zealand, Africa, and Indonesia) that this species spreads
rapidly through root suckers and seed (Richardson and Rejma´nek 2011; Richardson et al.,
2015). The invasion by an alien species of A. decurrens can proliferate as a pioneer plant in
an area where the native species can not to adapt to environmental conditions (Sunardi et
al., 2015; Sunardi et al., 2017). It creates negative consequences, especially for native
biodiversity (Sunardi et al., 2017). In Indonesia, the invasiveness of A. decurrens is found
several areas such as Mount Merapi after eruption 2006 (Suryanto et al., 2010 a,b) and 2010
(Afrianto et al. 2016; Sunardi et al., 2017; Afrianto et al., 2017, Afrianto et al., 2020), Mount
Merbabu (Purwaningsih, 2010; Untoro et al. 2017), Kawah Ijen Nature Tourism Park
(Hapsari et al. 2014), and Mount Panderman Nature Tourism (Septiadi. 2018).

Species distribution models (SDMs) can predict the effect on potential species
distributions under climate change at the single-species and community levels (Sung et al.,
2018). The study aimed to develop a SDM of A. deccurens to project the potential
distribution under climate change in Indonesia. Therefore, understanding the SDM of the
potential distribution of the invasive species under and future climate change can be used
as early preventive and management strategies for managing and handling the invasion.

Materials and Methods
Data collection

This study was analyzed by the Biodiversity and Climate Change Virtual Laboratory
(BCCVL) (http://www.bccvl.org.au/). BCCVL is cloud-based, providing access to modeling
tools, large species distribution, climate, the collection of biological and other
environmental datasets, and diverse experiment categories to carry out a study into the
relationship between biodiversity and climate change (Hallgren et al., 2016). The Global
Biodiversity Information Facility (GBIF) (http://www.gbif.org/) dataset of A. decurrens was
used to conduct the species occurrence (GBIF 2021). Worldclim current conditions (1950-
2000) at 2.5 arcmin was used in this simulation. Based on the database, A. decurrens has
about 17,917 occurrence records and 17,232 geo-referenced. Then, this data was imported
in BCCVL. The climate and environmental data used WorldClim, current climate (1950-
2000), 2.5 arcmin (~5km). These bioclimatic variables were generated using 1950 to 2000
from an array of global climate layers (except Antarctica). Eight climate variables were
chosen in the BCCVL, such as:

1. B04 (temperature seasonality, standard deviation)
2. B05 (max temperature of warmest month)
3. B06 (min temperature of coldest month)
4. B08 (mean temperature of wettest quarter)
5. B09 (mean temperature of driest quarter)
6. B13 (precipitation of wettest month)
7. B14 (precipitation of driest month) and,
8. B15 (precipitation seasonality, coefficient of variation).
The temperature and precipitation data were chosen because they are important

International Journal of Applied Biology, 5(2), 2021

factors to impact vegetation range and abundance of species (Krebs, 1985). Afrianto et al.,
(2017) state that the habitat preferences of A. decurrens were strongly correlated with
temperature conditions. Because we do not have a true absence dataset for the
experiment, we used the pseudo absence configuration (PA models) with the absence-
presence ratio of 1, the random pseudo-absence strategy, and the number of background
points of 10,000. Pseudo-absence points were used to generate for the experiment.

Data analysis

The experiment was conducted by the primary experiment of SDM experiment. For
the algorithm of SDM, we used Generalized Linear Model (GLM). The GLM is a linear
regression model to predict the response variable as a function of multiple predictor
variables. The GLM was used because it has several advantages, namely (1) the response
variable be able to all form of the exponential distribution model, (2) can be used in
categorical predictors, (3) easy to interpret and understand how each of the indicators is
impacting the outcome, (4) less vulnerable to overfitting than for instance CTA or MARS
algorithms. The area under the curve (AUC) of the receiver operating characteristics (ROC)
curve was used to examine model robustness. This curve is a non-parametric threshold-
independent measure of accuracy used to assess SDM (Bertelsmeier & Courchamp. 2014).
The x-axis of the ROC plot is a graph of the false positive rate (1- specificity), and the y-axis is
an actual positive rate (sensitivity). The values above 0.5 means prediction better than
random, and the value of 0.5 means a random prediction. The AUC score was classified as
follow (Crego et al., 2014):

A. Value above 0.9 is excellent
B. Good 0.9 > AUC > 0.8
C. Fair 0.8 > AUC > 0.7
D. Poor 0.7 > AUC > 0.6, and
E. Fail 0.6 > AUC > 0.5
Further analysis was conducted by the secondary experiment that is the climate

experiment, to investigate the distribution of a species under potential future climatic
conditions. A climate change experiment predicted A. decurrens distribution with the
climate information under climate change scenarios. In this study, we selected four IPCC
Representative Concentration Pathways (RCP) 2.6, 4.5, 6.0, and 8.5 for the 2050s.
Furthermore, we evaluated by (1) WorldClim, future projection using IPSL-CM5A-LR RCP 2.6
10 arcmin (2050), (2) WorldClim, future projection using IPSL CM5A-LR RCP 4.5, 10 arcmin
(2050), (3) WorldClim, future projection using IPSL-CM5A-LR RCP 6.0, 10 arcmin (2050), and
(4) WorldClim, future projection using IPSL-CM5ALR RCP 8.5, 10 arcmin (2050). The
prediction results based on the current climate condition indicate distribution of suitable
habitat.

RESULTS AND DISSCUSSION
Present distribution of A. decurrens in Indonesia

The introduction of A. decurrens in Indonesia is for industrial purposes. This exotic
plant species is planted as crops plants or plantations such as mahogany, pine, agathist,
coffee, cocoa, palm oil, acacia, African wood, and others. Exotic species introduced in
Indonesia are listed as industrial plants. including A. decurrens since ancient times of Dutch
colonialism (Purwaningsih, 2010).

The prediction of the current distribution of A. decurrens showed that mostly this

International Journal of Applied Biology, 5(2), 2021

species occurred in Sumatra and Sulawesi Island. In Sumatra Island, A. decurrens distributed
to several provinces Banda Aceh, North Sumatera, West Sumatera, and Bengkulu. In
contrast, in Sulawesi Island, this invasive species spread to West Sulawesi, Central Sulawesi,
and some parts of along with Southeast Sulawesi (Figure 1). However, until now, no
scientific documents and reports explain the occurrence of A. decurrens in these areas.
Mostly, the studies of A. decurrens is only found in Java Island, especially in Mount Merapi
National Park. Based on the report GBIF, in Indonesia A. decurrens has less for the
invasiveness impact with 42 occurrences reported (GBIF, 2021). On the other hand, the
highest occurrence is found in Colombia of 12,725 occurrences and has the highest
invasiveness impact of A. decurrens.

Figure 1. Map of current distribution of IAS of A. decurrens under current climate

condition in Indonesia using GLM algorithm in BCCVL. Darker areas represent a higher
potential distribution of A. decurrens.

By “invasion pathway” or the stages of invasion, there are five nonexclusive

consequences of climate change for invasive species, namely (1) modified transport and
initiation mechanisms, (2) establishment stage by new invasive species in the area, (3)
modified impact of existing invasive species, (4) the spreading of invasive species, and (5)
modified effectiveness of control approach (Hellman et al., 2008). The distribution of
invasive species under climate change is found more invader in outside protected areas of
Europe's marine and terrestrial because of the low human accessibility (Gallardo et al.,
2017). Panda et al., (2017) state the phenology and capacity of species to adapt quickly in
climate are potentially related to the invasion stage in the future climate.

Potential future distribution under climate change of A. decurrens in Indonesia

Climate change condition is likely to decrease the potential of the distribution of
A. decurrens in Indonesia. Figure 2 shows that A. deccurens in Sumatra Island was only
found in Banda Aceh Province based on IPCC RCP 2.6, 4.5, 6.0, and 8.5 for 2050, and some
part of North Sumatera (Pemantang Siantar) based on IPCC RCP 2.6 and 4.5 for 2050.
Moreover, Figure 3 shows that A. decurrens in Sulawesi Island were only found in Central
Sulawesi and South Sulawesi based on IPCC RCP 2.6, 4.5, and 6.0 for 2050.

International Journal of Applied Biology, 5(2), 2021

Figure 2. Comparison of climate change models of A. decurens for current and 2050 in

Kalimantan Island. (A) Current distribution, and (B-2) IPCC RCP 2.6, 4.5, 6.0, and 8.5 for the
2050 were evaluated with WorldClim data and 10 arcmin resolution. Darker areas

represent a higher potential distribution of A. decurrens.

International Journal of Applied Biology, 5(2), 2021

Figure 3. Comparison of climate change models of A. decurens for current and 2050 in

Sulawesi Island. (A) Current distribution, and (B-2) IPCC RCP 2.6, 4.5, 6.0, and 8.5 for the
2050 were evaluated with WorldClim data and 10 arcmin resolution. Darker areas

represent a higher potential distribution of A. decurrens.

Except for B09 (mean temperature of driest quarter), all climate variables used in
this study are responsive to A. decurrens distribution (Figure 4). A. decurrens was found in
areas that have moderate frost tolerance. It grows in the warm sub-humid to the humid
climatic zone. The environmental requirement of A. deccurens needs annual rainfall of 900-
1150 mm. It can grow with a mean minimum of the coolest month of 1-5°C, or it will even
tolerate temperatures as low as -6°C. On the other hand, the mean maximum of the hottest
month is 26-30°C. In general, the ROC plot showed excellent values (0.99) (Figure 5).

The climate change predicted will make several species losses in 2050 (Gallagher et
al. 2012). This phenomenon is because climate change will make a warmer condition where
it may impact the flowering and seedling of several plant species (Germishuizen and
Gardner 2015; Booth 2017). The short term of climate change is predicted to affect
abundance and distribution (Blyth et al. 2021). In a different result, Sutomo et al. (2017)
shows that the distribution prediction of A. nilotica in 2045 will increase, especially in
eastern Indonesia. Kriticos et al., (2003), also state SDM of A. nilotica might rising
significantly because of climate change. It is because A. nilotica can grow in temperature
around ~35 °C or 5°C warmer rather than A. deccurens.

This model prediction does not include other factors that are considered to impact
the distribution of A. decurrens. Those factors are edaphic, topographic, and dispersal
agent. It is because this species has values both economically and ecologically, thence social
aspects are also required to be analysed (Sutomo et al., 2021 a,b). By adding those
variables, it will make the prediction more powerful (Booth, 2018).

International Journal of Applied Biology, 5(2), 2021

Figure 4. The response curve for A. decurrens distribution model.

Figure 5. ROC plot of A. decurrens model using GLM in BCCVL.

CONCLUSIONS
A. decurrens will decrease in 2025 based on the current and future climate variables

conditions. Except for the mean temperature of the driest quarter, all climate variables used
in this study were responsive to A. decurrens distribution, and the ROC plot showed
excellent values (0.99). This study provides great tools to determine the impacts of climate
change on the IAS of A. decurrens for management purposes.

International Journal of Applied Biology, 5(2), 2021

REFERENCES
Afrianto, W.F., Hikmat, A & Widyamotoko, D. 2020. Plant Species Diversity and Degree of

Homogeneity After The 2010 Eruption of Mount Merapi, Indonesia. Biosaintifika:
Journal of Biology & Biology Education. 12(2) : 274-281.

Afrianto, W.F., Hikmat, A & Widyamotoko, D. 2017. Growth and Habitat Preferences of
Acacia decurrens Willd. (Fabaceae) After The 2010 Eruption of Mount Merapi,
Indonesia. Asian Journal of Applied Science. 5 (1) : 65-72

Afrianto, W.F., Hikmat. A & Widyamotoko, D. 2016. Floristic Community and Vegetation
Succession After The 2010 Eruption of Mount Merapi Central Java. Jurnal Biologi
Indonesia. 12 (2) : 265-276. [Indonesian]

Bamidele, O., Nnana, M., Imelda, L & Sekomeng, M. 2017. Acacia decurrens (Wild) An
Invasive South Africa Tree: Chemical Profile, Antibacterial and Antioxidant
Activities. Organic and Medicinal Chemistry International Journal. 3(3) : 1-9.

Bazie, Z., Feyssa, S & Amare, T. 2020. Effects of Acacia decurrens Willd. Tree-Based Farming
System on Soil Quality in Guder Watershed, North Western Highlands of
Ethiopia. Cogent Food & Agriculture. 6(1) : 1743622.

Booth, T.H. 2017. Assessing Species Climatic Requirements Beyond the Realized Niche:
Some Lessons Mainly from Tree Species Distribution Modelling. Climatic Change.
145(3) : 259-271.

Booth, T.H. 2018. Species Distribution Modelling Tools and Databases to Assist Managing
Forests Under Climate Change. Forest Ecology and Management. 430 : 196-203.

Blyth, C., Christmas, M.J., Bickerton, D.C., Breed, M.E., Foster, N.R., Guerin, G.R., Mason.
A.R.G & Lowe, A.J. 2021. Genomic, Habitat, And Leaf Shape Analyses Reveal a
Possible Cryptic Species and Vulnerability to Climate Change in A Threatened
Daisy. Life. 11(6) : 553.

CABI. 2021. Acacia decurrens (green wattle). Retrieved from:
https://www.cabi.org/isc/datasheet/2208.

Chanie, Y & Abewa, A. 2021. Expansion of Acacia decurrens Plantation on the Acidic
Highlands of Awi zone, Ethiopia, and Its Socio-Economic Benefits. Cogent Food &
Agriculture. 7(1) : 1917150.

Endalew, B.A., Adigo, E & Argaw, M. 2014. Impact of Land Use Types on Soil Acidity in The
Highlands of Ethiopia: The Case of Fageta Lekoma District. Academia Journal of
Environmental Sciences. 2(8) :124–132.

Gallagher, R. V., Hughes, L & Leishman, M. R. 2013. Species Loss And Gain In Communities
Under Future Climate Change: Consequences For Functional Diversity.
Ecography. 36(5) : 531-540.

International Journal of Applied Biology, 5(2), 2021

GBIF. 2016. Acacia decurrens (J.C.Wendl.) Willd. Retrieved from:
https://www.gbif.org/species/2979778.

Germishuizen, I. & Gardner, R.A. 2015. A Tool for Identifying Potential Eucalyptus nitens
Seed Orchard Sites Based On Climate and Topography. Southern Forests: A
Journal of Forest Science. 77(2) : 123-130.

Gollardo, B., Aldrige, D.C., González-Moreno, P., Pergl, J., Pizarro, M., Pyšek, P., Thuiller, W.,
Yesson, C & Vilà, M. 2017. Protected Areas Offer Refuge from Invasive Species
Spreading Under Climate Change. Global Change Biology. 23(12) : 5331-5343.

Hapsari, L., Basith. A & Novitasiah, H.R. 2014. Inventory of Invasive Plant Species Along the
Corridor of Kawah Ijen nature Tourism Park, Banyuwangi, East Java. Journal of
Indonesian Tourism and Development Studies. 2(1) : 1-9.

Hellmann, J.J., Byers, J.E., Bierwagen, B.G & Dukes JS. 2008. Five potential consequences of
climate change for invasive species. Conservation Biology. 22(3) : 534-543.

Krebs, C.J. 1985. Ecology: The Experimental Analysis of Distribution and Abundance. Harper
& Row, New York.

Kriticos, D.J., Sutherst, R.W., Brown, J.R., Adkins, S.W & Maywald, G.F. 2003. Climate Change
and The Potential Distribution of an Invasive Alien Plant: Acacia nilotica ssp.
Indica in Australia. Journal of Applied Ecology. 40(1) : 111-124.

Molla, A & Linger, E. 2017. Effects of Acacia decurrens (Green Wattle) Tree On Selected Soil
Physico-Chemical Properties North-western Ethiopia. Res J Agric Environ Manag.
6(5) : 95-103.

Nigussie, Z., Tsunekawa, A., Haregeweyn, N., Adgo, E., Nohmi, M., Tsubo, M., Akloh, D.,
Meshesha, D.T & Abele S. 2016. Factors Affecting Small-Scale Farmers’ Land
Allocation and Tree Density Decisions in an Acacia decurrens-Based Taungya
System in Fagita Lekoma District, North-Western Ethiopia. Small-Scale Forestry.
16(2) : 219–233.

Nigussie, Z., Tsunekawa, A., Haregeweyn, N., Adgo, E., Tsubo, M., Ayalew, Z & Abele S. 2020.
Economic and Financial Sustainability of an Acacia decurrens-Based Taungya
System for Farmers in the Upper Blue Nile Basin, Ethiopia. Land Use Policy. 90:
104331.

Nigussi, Z., Tsunekawa, A., Haregeweyn, N., Tsubo, M., Adgo, E., Ayalew, Z. & Abele S. 2021.
The Impacts of Acacia decurrens Plantations on Livelihoods in Rural Ethiopia.
Land Use Policy. 100 : 104928.

Panda, R.M., Behera, M.D & Roy PS. 2018. Assessing Distributions of Two Invasive Species of
Contrasting Habits In Future Climate. Journal of Environmental Management.
213 : 478–488.

International Journal of Applied Biology, 5(2), 2021

Purwaningsih. 2010. Acacia decurrens Wild: Jenis Eksotik dan Invasif di Taman Nasional
Gunung Merbabu, Jawa Tengah. Berkala Penelitian Hayati. 4A: 23-28.
[Indonesian]

Reubens, B., Moeremans, C., Poesen, J., Nyssen, J., Tewoldeberhan, S., Franzel, S., Deckers,
J., Orwa, C & Muys, B. 2011. Tree Species Selection for Land Rehabilitation in
Ethiopia: From Fragmented Knowledge to an Integrated Multi-Criteria Decision
Approach. Agroforestry Systems. 82(3) : 303-330.

Richardson, D.M., Le Roux, J.J & Wilson, J.R. 2015. Australian Acacias as Invasive Species:
Lessons to Be Learnt from Regions with Long Planting Histories. Southern
Forests: A Journal of Forest Science. 77(1) : 31–39.

Richardson, D.M & Rejmánek M. 2011. Trees and Shrubs as Invasive Alien Species - A Global
Review. Diversity and Distributions. 17(5) : 788–809.

Septiadi, L., Wahyudi, D., Rachman, R.S., Syafrudin & Alfaruqi, N.T.S. 2018. The Invasive
Plants Species Along the Hiking Track of Mount Panderman Nature Tourism,
Batu, East Java. Journal of Indonesian Tourism and Development Studies. 6 (1) :
55-62.

Sunardi, S., Sulistijorini, S & Setyawati. T. 2017. Invasion of Acacia decurrens Willd. After
Eruption of Mount Merapi, Indonesia. Biotropia: The Southeast Asian Journal of
Tropical Biology. 24(1) : 35-46.

Sunardi, Sulistijorini & Setyawati, T. 2015. Volcano Eruption and Invasion of Acacia
decurrens (Wendl.) Wild in Mount Merapi National Park. In: Miftahudin, Juliandi
B, Muttaqin M (eds). Proceedings Papers of International Conference on
Biosciences 2015. Institut Pertanian Bogor International Convention Center,
Bogor, 5-7 August 2015.

Sung, S., Kwon,Y.S., Lee, D.K & Cho, Y. 2018. Predicting The Potential Distribution of an
Invasive Species, Solenopsis invicta Buren (Hymenoptera: Formicidae), Under
Climate Change Using Species Distribution Models. Entomological Research.
48(6) : 505-513.

Suryanto, P., Hamzah. M.Z., Alias, M.A & Mohamed, A. 2010a. Post-Eruption Species
Dynamic of Gunung Merapi National Park, Java, Indonesia. Journal of Tropical
Biology & Conservation. 7: 49-57.

Suryanto, P., Hamzah, M.Z., Mohamed, A & Alias MA. 2010. The Dynamic Growth And
Standing Stock of Acacia decurrens Following the 2006 Eruption in Gunung
Merapi National Park, Java, Indonesia. International Journal of Biology. 2(2) :
165-170.

Sutomo & van Etten E. 2017. Species Distribution Model of Invasive Alien Species Acacia
nilotica for Central-Eastern Indonesia Using Biodiversity Climate Change Virtual
Laboratory (BCCVL). Tropical Dryland. 1(1) : 36-42.

International Journal of Applied Biology, 5(2), 2021

Sutomo, Iryadi, R & Kurniawati F. 2021. Habitat Suitability Model of Agarwood in A Changing
Climate. The 5th International Conference on Climate Change 2020; IOP
Conference Series: Earth and Environmental Science 724 (1): 012022. Cibinong,
West Java, 18-20 November 2020.

Sutomo, Yulia, E., & Iryadi, R. 2021. Kirinyuh (Chromolaena odorata): species distribution
modeling and the potential use of fungal pathogens for its eradication. The 7th
International Symposium of Innovative Bio-Production Indonesia on
Biotechnology and Bioengineering 2020; IOP Conference Series: Earth and
Environmental Science 762 (1): 012023. Bali, Bali, 24-25 September 2020.

Untoro, Y., Hikmat, A & Prasetyo, L.B. 2017. The Spatial Suitable Habitat Model of Acacia
decurrens in Mount Merbabu National Park. Media Konservasi. 22(1) : 49-63.
[Indonesian].

Wondie, M & Mekuria, W. 2018. Planting of Acacia decurrens and Dynamics of Land Cover
Change in Fagita Lekoma District in the Northwestern Highlands of Ethiopia.
Mountain Research and Development. 38(3) : 230-239.

Wrigley, J.W & Fagg M. 2013. Australian Native Plants: Cultivation, Use in Landscaping and
Propagation. Reed New Holland. 4th edition. Reed New Holland, Australia.