Indonesian Journal of Forestry Research Vol. 8 No. 1, April 2021, 59-72

ISSN: 2355-7079/E-ISSN: 2406-8195

EARLY GROWTH OF JABON (Anthocephalus cadamba Miq)
IN A DRAINED PEATLAND OF PELALAWAN, RIAU
Ahmad Junaedi1*, Nina Mindawati2, and Yanto Rochmayanto3
Research Institute for Fiber Technology of Forest Plant Species;
Research, Development and Innovation Agency
Jl. Raya Bangkinang - Kuok, Kec. Kuok, Kab. Kampar, Prov. Riau, Indonesia
2
Forest Research and Development Center, Research, Development and Innovation Agency
Jl. Gunung Batu No.5, Bogor, West Java 16610, Indonesia
3
Center for Research and Development on Social, Economy, Policy and Climate Change,
Research, Development and Innovation Agency
Jl. Gunung Batu No.5, Bogor, West Java 16610, Indonesia
1

Received: 21 September 2020, Revised: 11 April 2021, Accepted: 12 April 2021
EARLY GROWTH OF JABON (Anthocephalus cadamba Miq.) IN A DRAINED PEATLAND OF
PELALAWAN, RIAU. The desirability to explore other tree species that can be used to substitute Acacia
crassicarpa in forest plantation has increased. One of the early insights that must be known is the growth
performances of tree species candidates, especially in planting conditions (site and silviculture) similar to
A. crassicarpa plantation. This study evaluated the growth performance of jabon (A. cadamba Miq.) and
its relationship with soil properties in a drained peatland. The research was conducted by establishing
experimental plots of jabon in a drained peatland (DP) using a randomised complete block design with
three spacing (2 m x 3 m, 2.5 m x 3 m, 3 m x 3 m) as treatment and three blocks as replications. The
study observed survival, growth and soil chemical properties. At 24 months after planting (MaP), since the
toxicity of soil micronutrients was excessive as one of the main factors; the mortality rate of jabon was high
(62%), while its growth was poor (height = 259 cm and DBH = 3.74 cm) in drained peatland. However, the
study observed that 7% of jabon had good growth, with a range of height growth at 24 MaP of 401–660
cm. These results indicated that though overall jabon did not show good growth in DP, however, it was
found that 7% of jabon had promising growth; therefore, it was suggested that through tree improvement
program and certain treatments to overcome micronutrient toxicity and weed suppression, the possibility of
jabon was able to be developed in a DP for forest plantation is still.
Keywords: Growth, Anthocephalus cadamba, Acacia crassicarpa, micronutrients toxicity, tree improvement
PERTUMBUHAN AWAL JABON (Anthocephalus cadamba Miq.) PADA LAHAN GAMBUT YANG
DIDRAINASE DI PELALAWAN, RIAU. Dorongan untuk mencari jenis pohon sebagai pengganti A. crassicarpa
di hutan tanaman semakin meningkat. Salah satu informasi awal yang perlu diketahui adalah mengenai pertumbuhan calon
pohon yang akan dipilih pada kondisi pertanaman yang sama dengan A. crassicarpa. Penelitian ini mengevaluasi pertumbuhan
jabon (A. cadamba) dan hubungannya dengan sifat tanah di lahan gambut yang didrainase. Penelitian dilakukan dengan
membangun plot eksperimen penanaman jabon di lahan gambut yang didrainase, menggunakan rancangan acak kelompok
dengan tiga jarak tanam (2 x 2 m; 2,5 m x 3 m; 3 m x 3 m) sebagai perlakuan dan diulang sebanyak tiga blok ulangan.
Parameter yang diamati meliputi kemampuan hidup, pertumbuhan dan sifat kimia tanah. Sampai umur 24 bulan setelah
tanam (BST), jabon menunjukkan tingkat kematian yang tinggi (62%) dan rerata pertumbuhan yang lambat (tinggi 259
cm dan diameter 3,74 cm) di lahan gambut yang didrainase dikarenakan salah satunya oleh keracunan hara mikro berlebih.
Meskipun demikian, sebanyak 7% jabon mempunyai pertumbuhan tinggi yang baik pada umur 24 BST, yakni berkisar
401–660 m. Hasil tersebut menunjukkan bahwa secara keseluruhan jabon tidak menunjukkan pertumbuhan yang baik
di lahan gambut yang didrainase. Namun, adanya sebagian jabon (7%) yang menunjukkan performa yang menjanjikan;
maka melalui program pemuliaan pohon dan perlakuan silvikultur untuk mengatasi permasalahan keracunan hara mikro
berlebih dan tekanan gulma, nampaknya jabon masih berpeluang untuk dikembangkan di lahan gambut yang didrainase.
diharapkan jenis ini dapat dikembangkan melalui program pemuliaan pohon dan perlakuan silvikultur untuk mengatasi
permasalahan keracunan hara mikro berlebih dan tekanan gulma.
Kata kunci: Pertumbuhan, Anthocephalus cadamba, Acacia crassicarpa, keracunan hara mikro, pemuliaan pohon
*

Corresponding author: ajunaedi81@yahoo.co.id

©2021 IJFR All rights reserved. Open access under CC BY-NC-SA license. doi:10.20886/ijfr.2021.8.1.59-72

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Indonesian Journal of Forestry Research Vol. 8 No. 1, April 2021, 59-72

I. INTRODUCTION
Indonesia is one of ten countries with the
largest area of forest plantations in the world
(Indufor, 2014, as cited by Barua, 2015). In
total, the coverage area of forest plantations
in Indonesia till 2019 reached around 5.1
million ha, and one of the most vital of that
is pulpwood plantation/HTI-pulp (Ministry of
Environment and Forestry, 2021). However, the
productivity of HTI-pulp has decreased due to
the low density of standing stock at harvest
time. The survival rate of stand-in HTI-pulp at
five years could reach less than 25% (Junaedi,
2018b).
The decreasing HTI-pulp productivity
existed in all land types, including in the
peatland of Riau Province, expressed by the low
productivity of Acacia crassicarpa (krassikarpa).
The productivity of this species in second
rotations was less than 140 m3/ha (Suhartati,
Aprianis, Pribadi, & Rahmayanto, 2013).
Therefore, the decreasing HTI pulp productivity
should be solved; due to Riau has a large area
of HTI-pulp plantations (800 thousand ha),
and more than 50% was in peatland (Ministry
of Environment and Forestry, 2016). One way
to prevent a continual decline in HTI-pulp
productivity is to explore alternative species
that can grow well on peatland.
Jabon (Anthocephalus cadamba Miq.) was
selected in this study as the tree species
candidate that would be further evaluated for
its probability to be grown in the peatland of
HTI-pulp. Jabon is a pioneer species that can
grow well in acidic soil and has been categorised
as fast-growing species (Bijalwan, Dobriyal,
& Bhartiya, 2014b; Suhartati, Rahmayanti, &
Nurrohman, 2012). Furthermore, in a term as
raw material for pulp and paper, fiberwood of
jabon had good quality (Aprianis, 2016; Biswas,
Misbahuddin, Roy, Francis, & Bose, 2011).
In this study, the focus of the evaluation was
on growth performances in the three planted
spacing of the species in the conditions (site
and silviculture) that were in general similar to
krassikarpa plantation. A previous study of the

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growth of jabon in acidic ultisol soil showed
that the growth performance of jabon was
influenced by soil properties (Junaedi, 2018a);
thus, the current study also investigated the role
of soil properties on jabon growth. Therefore,
the objectives of this study to evaluate the growth
performance of jabon in peatland in general
term and to evaluate growth performance of
jabon in peatland as the effect of variation
in planted spacing, and to investigate the
relationship between the growth of jabon and
soil properties in peatland. Furthermore, due to
the standard of site management of peatland
for HTI-pulp, the area has been drained; hence
the scope of evaluation was for jabon, which
was grown in drained peatland.
II. MATERIAL AND METHOD
1. Site Description
The study was conducted in a peatland that
has been under forest concession of PT. Riau
Andalan Pulp and Paper (RAPP). The location
is at Pelalawan Sector, Compartment C-047
(based on estate administration, 00º32.071' N
and 102º05.469' E), Pelalawan District, Riau
(Figure 1). The soil type of location is histosol
with its dominant maturity of organic materials
is fibric-hemic. Elevation of the location is
at 8 m. Elevation of the location is at 8 m
a.s.l. The climate type of the location is A,
with an average annual temperature, relative
humidity and rainfall of 27ºC; 84%; 2,100 mm,
respectively. The land was drained; the water
table depth was kept more than 50 cm below
the soil surface (Christianus, 2006). Previously,
the land was used for the plantation forest of
krassikarpa (second rotation).
2. Plot Establishment
The experimental plot was established
based on the silviculture system commonly
applied in RAPP for krassikarpa (Junaedi,
2018b). The targeted area was cleared using an
excavator, and plots were established. There
were three different spacing evaluated in this
study, i.e. 2 x 2 m, 2.5 x 3 m and 3 x 3 m. The

Early Growth of Jabon (Anthocephalus Cadamba Miq) In a Drained Peatland ......(Ahmad Junaedi et al.)

Figure 1. Location of the trial site in Pelalawan District, Riau

Figure 2. The design of experimental plots of jabon in a drained peatland of Pelalawan, Riau
Remarks: S1 = 2 m x 2 m, S2 = 2.5 m x 3 m and S3 = 3 m x 3 m

seedlings of jabon were planted according to
a randomised complete block design (RCBD)
with those spacing as single treatments and
with three replications (Figure 2). The age of
seedlings used for the plantation was about
four months with the means of height and
collar diameters of 18.5 cm and 4.38 mm,
respectively. The seedling originated from
generative propagation, and the seed origin was
identified by standing seed sources in Dramaga,
Bogor, West Java (unimproved seed).
Similar fertilisation was applied when
planting for all spacing treatment. The types and
dosages per seedling were 250 g rock phosphate

(Ca3(PO4)2CaF), 50 g KCl, 10 g Ertibor (Na2
B4O7·5H2O) and 10 g zincop (ZnSO4.H2O
& CuSO4.7H2O). A year after planting, jabon
was intensively maintained through frequent
weeding in three monthly intervals (manually
with machete and hand removal) and one time
pruning at six months after planting. Initially,
based on the standard silviculture technique of
krassikarpa, maintenance was not continued
after one year. However, we found the weed
was very dense in the plots when making the
growth observation at the age of 18 months
after planting (18 MaP); thus, a supplement
weeding was done (once) after 18 MaP.

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Indonesian Journal of Forestry Research Vol. 8 No. 1, April 2021, 59-72

3. Field Measurements
The survival rates and growth of jabon
were measured at the ages of 3, 6, 12, 18, and
24 months after planting (MaP). The initial
planning of observation was to continue till
harvest time (i.e. five years). In terms of growth
evaluation for pulpwood plantation, the study
decided to not continue observation at the age
after 24 MaP (2 years). The survival rate was
very low and tended to continue to decrease. In
contrast, the growth rate tended to a standstill.
The observation of all variables was undertaken
based on spacing differences at 3, 6, and 12
MaP. However, this spacing difference was not
followed during the observation at 18 MaP due
to the high mortality of jabon in each spacing.
The number of live individuals was recorded
during the time of observations. The survival
rate then was quantified as the percentage/
proportion of individuals remaining after 3, 6,
12, 18, and 24 months since seedling planting.
The observation of growth parameters was
conducted on total height (cm) and diameter
breast height (DBH, cm). Total height was
observed at all time of observations, while
DBH was recorded at 18 MaP and 24 MaP.
Height was measured by measuring stick, while
DBH by the calliper.
The soil properties were identified twice
to examine the relationship between growth
and soil properties. The first, soil sample was
collected from five points (four points at each
corners of plot and one point at the center;
depth = 0–30 cm) from the experiment plot
and then combined to result in one composite
sample. This work was done immediately after
planting. Secondly, soil samples were collected
at 7 MaP on two different locations based on
the growth data of 6 MaP. The locations were
under stunted (jabon A) and good jabon (jabon
B).
Soil samples were sent to the soil laboratory
of the Forestry Research and Development
Division, PT. RAPP in Pangkalan Kerinci, Riau
for chemical analysis. Soil samples were analysed
for content of total C (colourimetric method);
total N (Kjeldahl method); the availability of P
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(bray II method), K, Ca and Mg (NH4OAc (pH
7.0, 1 N) extraction method); total B, Cu, Zn,
Fe, Mn (HCl 25% extraction method) and total
Al (HNO3+HClO4 extraction method) (Bray, &
Kurtz, 1945; Bremner & Mulvaney, 1982; Eviati
& Sulaeman, 2009; Motsara & Roy, 2008).
4. Data Analysis
One-Way ANOVA was performed to
determine the effect of spacing on jabon
growth at 3–12 MaP periods. However,
ANOVA analysis was not run at 18 and 24
MaP to avoid bias. The possibility of bias was
revealed due to high mortality caused by the
massive change in current spacing compared to
initial spacing treatments. Therefore, the data at
18 and 24 MaP was analysed with descriptive
analyses followed with descriptions in tabular
and graphical forms.
III. RESULTS AND DISCUSSION
A. The Survival Rate, Growth and Spacing
Effect
The survival rate of jabon at the age of
3–12 MaP period in drained peatland (DP) was
not significantly different (p>0.05), based on
spacing treatment. Furthermore, there was an
abnormal result in the trend of survival rate at
the age of 6–9 MaP period. The survival rate
at 9 MaP was higher than at 6 MaP (Figure 3a).
However, after 9 MaP, the survival declined till
the last observation (24 MaP) and reached 38%.
This abnormal survival rate may be due to the
number of trees that were observed as dead
plants at the age of 3 and 6 MaP, categorised by
physical symptoms such as wilting, defoliating
and drying; however, several of them were regreening, and re-sprouting at 9 MaP; and thus
were identified as live individuals.
Height of jabon was not significantly
different (p>0.05) between spacing treatments at
the age of 3–12 MaP (Figure 3b). Furthermore,
the increment of height and DBH showed
relatively promising growth of jabon till 18
MaP (height increment=170 cm/year and
DBH increment=1.72 cm/year). However,
the height growth between 18–24 MaP was at

Early Growth of Jabon (Anthocephalus Cadamba Miq) In a Drained Peatland ......(Ahmad Junaedi et al.)

Figure 3. The survival rate (a), height growth (b) and diameter growth (c) of jabon in drained peatland

a standstill, even for the DBH, and a negative
growth increment was observed (Figure 3c). At
24 MaP, the average height and DBH based on
whole live individuals' data were 259 cm and
3.74 cm. The stagnant or negative increment of
growth of jabon in DP probably was because
several jabon did not survive after reaching 24
MaP. Therefore, the average growth tended
to a standstill for height and was negative for
diameter.
Spacing treatment can influence plant
competition in access to water, nutrient and
sunlight (Ximenes, Mayun, & Pradnyawathi,
2018; Yudianto, Fajriani, & Aini, 2015). In
this study, intraspecific competition within
individual trees of jabon commenced from the
first establishment till 12 MaP. The competition
between jabon and other species (weed) could
be neglected because the weed was regularly
eradicated (three monthly). However, this

intraspecific competition during the observation
was not yet intensive. In this experiment, the
intraspecific competition occurred at the time
of early growth of jabon, when the resources
(water and nutrient) requirement of the plant
was relatively low. Moreover, the sunlight was
unlimited for all individuals of jabon in the
different spacing due to there was no canopy
closure till 12 MaP. As a result, the spacing
differences were not influenced yet on the
difference of resources required by plants.
Therefore, as previous results showed, the
growth of jabon in DP during 3–12 MaP
was not significantly different among spacing
treatments. Similar results have been found in
2 years old Eucalyptus spin Brazil (Filho, Molayudego, & González, 2018).
The classification of the height based on the
collected data from all live individuals (without
being distinguished by spacing differences)

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showed that most of jabon had slow growth
at the age of 6, 12, and 24 MaP (Figure 4). For
example, the proportion of height below 201
cm at the age of 24 MaP was 21% (Figure 4).
However, a few jabon (7%) showed promising
growth until 24 MaP, and height growth could
reach the range of 401–660 cm (Figure 4).
The high variation in growth between
individuals of jabon may be because the seed
source used in this experiment came from the
identified seed source in Dramaga, Bogor,
East Java. Seeds originated from an identified
seed source class means that seeds are not yet
superior. This is because the seed source has
not yet been selected from a parent tree with
good growth, nor was thinning done, resulting
in bad quality trees. This causes a large variation
in growth and survival rate when planted in
other places. The progeny test of jabon also
supported this suggestion in Java, Indonesia,
which showed that the difference in height and
diameter of jabon was greater among families
than among provenances (Sudrajat, Nurhasybi,
Siregar, Siregar, Mansur, & Khumaida, 2016).
Moreover, another factor that seems like
the main factor in this growth variation in
soil properties. However, specifically, the

ISSN: 2355-7079/E-ISSN: 2406-8195

explanation of the effect of soil properties
would be discussed further.
Overall, the results showed that jabon in
DP had a low survival rate till 24 MaP (2 years
after planting). The survival rate was less than
60% (The Regulation of Forestry Ministry
about a Manual for Evaluate the Successful of
Forest Reclamation, 2009). Of course, this is an
unexpected result, even though the observation
was only made relatively young, not yet at
harvest time. At a similar age, this survival rate
was lower than that found in jabon in ultisol
land (84%) and also than that in krassikarpa
(exotic species) with a survival rate of more than
80% (Junaedi, 2018a; 2018b). Furthermore, for
native tree species of tropical peat swamp forest
(TPSF); the survival rate range of the pioneer
(i.e. mahang (Macaranga pruinosa), geronggang
(Cratoxylum arborescens), and skubung (Macaranga
gigantea) and non-pioneer i.e. kelat (Eugenia sp.),
kapurnaga (Calophyllum sp.), punak (Tetramerista
glabra), and ramin (Gonystylus bancanus) species
were 71–94% and 37–90% (Daryono, 2009;
Junaedi, 2018b).
Jabon growth also showed an unexpected
result. Overall, in point of view, as fast-growing

Figure 4. The distribution (%) of jabon height in some classes at 6, 12 and 24 MaP

64

Early Growth of Jabon (Anthocephalus Cadamba Miq) In a Drained Peatland ......(Ahmad Junaedi et al.)

species, the growth of jabon in DP was poor.
As fast-growing species, some previous studies
showed that the height and DBH increments
of jabon at 2–4 years in dryland could reach
1.62–4.21 m/year and 2.03–5.25 cm/year
(Abdulah, Mindawati, Kosasih, & Darwo, 2013;
Bijalwan, Dobriyal, & Bhartiya, 2014a; Seo,
Chun, Mansur, & Lee, 2015; Wahyudi, 2012;
Zuhaidi, Hashim, Sarifah, & Norhazaedawati,
2012; Zuhaidi, 2013). It means that the height
and DBH of jabon in optimal growth in DP
could reach 3.24–8.42 m and 4.06–10.50 cm at
the age of 24 MaP, but in this study, it was 2.59
m and 3.74 cm, respectively. The growth of
jabon in DP was not better than that of jabon
in marginal ultisol land with the average height
and DBH, at the age of 24 MaP, of more than
3 m and 3 cm (Junaedi, 2018a).
The toxicity of soil micronutrient was
suggested as the main factor that made the
poor growth of jabon in DP (this study)
instead of in dryland as mentioned by Wahyudi
(2012) in Central Kalimantan, Ahmad Zuhaidi
(2013) in Sarawak-Malaysia, Seo, Kim, Chun,
Mansur, and Lee (2015) in West Java and
(Junaedi, 2018a) in Baserah-Riau. Possibly, it
was caused by the fact that the content of soil
micronutrient in dryland was less than that in
DP. For instance, the exchangeable Al content
in a ultisol soil at Baserah-Riau was less than 2.5
cmol (+) kg-1 (Junaedi, 2018a), while in peat soil
of Kalimantan was more than 3 cmol (+) kg-1

(Fahmi, Radjagukguk, Purwanto, & Hanudin,
2012). Therefore, the toxicity rate in jabon,
which was grown in dryland, was less than
that in DP. Furthermore, this toxicity will be
explained more in detail in the sub-discussion
of Effect of Soil Properties on The Growth.
Furthermore, compared with native tree
species of TPSF, the growth of jabon in DP
was not better than pioneer species of TPSF
such as mahang, skubung and geronggang.
However, compared to the growth of nonpioneer species of TPSF Parashorea smythiessii;
the growth of jabon was better than the growth
of slow-growing non-pioneer species such as
kelat (Eugenia sp.) and ramin (Gonystylus bancanus)
(Daryono, 2009; Hilwan, Setiadi, & Rachman,
2013; Junaedi, 2018b; Lampela, Jauhiainen,
Sarkkola, & Vasander, 2017; Subiakto, Rachmat,
& Sakai, 2016). The better performances of the
pioneer native species might be related to their
ability to overcome soil micronutrient toxicity
through mechanisms. For instance, geronggang
has a root system associated with arbuscular
mycorrhiza (AM)(Tawaraya et al., 2003). AM in
the root gives advantage to geronggang because
it can reduce the detrimental effect of soil
micronutrient toxicity (Rouphael, Cardarelli, &
Colla, 2015).
This study also suggested that one of the
main causal factors of mortality and poor
growth of jabon after 12 MaP was weed
suppression. The three monthly weedings

Figure 5. The high density (crowded) of weed around jabon stand at the age of 18 MaP in drained
peatland

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undertaken during the age of 0–12 MaP were
not continued further. Despite the impact,
the study did not specifically observe some
variables related to under-storey. Still, when the
growth observation was made at 18 MaP, the
study found dense weeds, particularly such as
seedling-poles of krassikarpa and some tropical
ferns (Figure 5). Moreover, the height of some
of the krassikarpa pole was higher than jabon
and shaded it. This evidence also showed that
the supplement weeding done after 18 MaP was
too late and insufficient to save the survival and
growth of jabon stand due to jabon is a pioneer
species that need an open area to capture
optimal sunlight their life and growth. This fact
was also suggested to make the better survival
rate and growth of jabon in a ultisol in Baserah,
Riau, where the weed control was undertaken
till 24 MaP (Junaedi, 2018a).
B. Effect of Soil Properties on The Growth
The chemical soil properties at the initial
condition showed that the content of primary
macronutrient (N, P and K) and micronutrient
(Al, Fe and Mn) were high-very high (Tabel 1).
Furthermore, the soil acidity was extremely acid.
The high content of total N was the common
condition in peat soil due to N's source from
organic matter, which is relatively abundant.
However, it was surprising that the content of
P and K was also high. It was presumed that
the high content of P and K had a relationship
with the application of rock phosphate/RP
(Ca3(PO4)2CaF) and KCl fertilisers. Before
establishing a jabon trial, RP as a P and KCl as a
source of K were applied in previous silviculture
practices to krassikarpa. As mentioned in the
method, the trial's location previously was used
for the plantation of krassikarpa. Furthermore,
the high acidity and micronutrient of Al, Fe
and Mn content were common facts in drained
peatland, as also were showed in some previous
studies (Agus et al., 2020; Hikmatullah &
Sukarman, 2014; Husnain, Wigena, Dariah,
Marwanto, Setyanto, & Agus, 2014; Tuukkanen,
Marttilla, & Klove, 2017).
The high content of soil macronutrient in

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the plot was a good initial condition to support
the growth of jabon. However, conversely, the
existing high soil micronutrient of Al, Mn and
Fe made the soil extremely acid that was very
harmful to the growth of jabon. In extremely
acid soil, micronutrient solubility such as Al
and Fe will increase and further toxic to the
plant (Soewandita, 2018). Especially for Al, the
potency of this element as a toxic element for the
plant was shown in several cultivated peatlands
in Central Kalimantan, South Kalimantan, Riau
and Jambi (Hikmatullah & Sukarman, 2014).
Furthermore, based on soil sample analysis
where the samples were collected from two
locations in the experiment plot at 7 MaP, the
soil properties tended to be different. The soil
macronutrient under good jabon (jabon B) was
higher than under stunted jabon (jabon A), but
vice versa for micronutrients of Fe and Mn
(Table 1).
Al in acidic soil (pH<5) demonstrated as
the main toxic metal for plant (Hodson, 2012;
Neenu & Karthika, 2019; Rahman, Lee, Ji,
Kabir, Jones, & Lee, 2018). Based on the data
of initial soil properties, the condition of the
plots expressed an extremely acid state and had
relatively high Al, and this suggested that the
Al toxicity was the main causal factor of the
massive mortality and suppressed the growth
of jabon, besides the use of unimproved seed
and weed factors. Despite, it could not explain
the detailed mechanism of the Al toxicity
in jabon in the present study yet. The data
associated with the physiology of the plant was
not observed. However, some previous studies
in other plants such as Vigna unguiculata, sugar
maple and soybean showed that Al toxicity
could inhibit nutrient uptake in the root system
and also hindering root cell division and its
elongation (Neenu & Karthika, 2019; Schaberg,
Tilley, Hawley, Dehayes, & Bailey, 2006; Yu,
Liu, Wang, Chen, & Xu, 2011).
Based on this study, it is suggested that the
role of soil micronutrient determine the growth
difference between jabon A and jabon B. As
reported before, the obtained micronutrient of
Fe and Mn under jabon A was higher than that

Early Growth of Jabon (Anthocephalus Cadamba Miq) In a Drained Peatland ......(Ahmad Junaedi et al.)

Table 1. Soil properties at initial condition, under stunted jabon (jabon A) and good jabon (jabon B)
Elements
pH H2O
Macronutrients :
- C
- Total N
- Available P
- Available Ca
- Available K
- Available Mg
Micronutrients :
- Available Na
- Total B
- Total Cu
- Total Fe
- Total Mn
- Total Zn
- Total Al

Unit

%
%
me/100 g
me/100 g
me/100 g
me/100 g
me/100 g
mg/kg
mg/kg
mg/kg
mg/kg
mg/kg
mg/kg

Initial condition
3.30 ± 0.08EA

Jabon A

Jabon B

3.217 EA

3.72 EA

45.5 ± 1.52VH

40.17 VH
1.46 VH
32.17 VH
1.06 VL
0.22 L
0.59 L

40.61 VH
1,46 VH
39.11 VH
5.77L
0.46 M
1.10 M

0.07 VL
5.82
4.5 S
995.60 VH

0.10 L
6.11
2.7 S
723.80 VH

77.05 VH
28.2

35.36 VH
25.10

1.3 ± 0.13
39.55 ± 4.49 VH
0.50 ± 0.08 VL
2.57 ± 1.07 VH
2.27 ± 0.17 H
VH

0.11 ± 0.006 L
3.65 ± 0.84
0.97 ± 0.51S
655.7 ± 228.5VH
10.16 ± 3.163H
3.31 ± 0.54
1.6 ± 94.03 VH

Remarks : VL=very low, L=low, M=moderate, H=high, VH=very high, EA=extremely acid, S=sufficient (Eviati &

Sulaeman, 2009)

under jabon B. The same as Al, the excessive
presence of Fe and Mn in the soil also would
be toxic for the plant. Moreover, the excessive
micronutrients such as Al, Mn and Fe also
negatively affected the growth of the plant
through the antagonistic role on macronutrient
uptake of P, K, Ca and Mg (Moosavi & Ronaghi,
2011). The possibility that the toxicity rate and
antagonistic role of those micronutrients in
jabon A were higher than that in jabon B, thus
the growth of jabon B was better than for jabon
A. This concurred with several previous studies
showing that some of the metal/micronutrients
such as Al, Fe and Mn were the limiting factors
in the growth and productivity of some plant/
crop (Choudhury & Sharma, 2014; Qadir,
Schubert, & Steffens, 2013; Rehmus, Bigalke,
Valarezo, Mora, & Wolfgang, 2014; Yu, Liu,
Wang, Chen, & Xu, 2011).
The degradation of
photosynthetic
pigments expressed the toxicity of Fe and Mn,
the substantial damage in the components of

root such as epidermal cells and membrane
lipid and the biochemical disorder in cell (Li
et al., 2012; Millaleo, Ivanov, Mora, & Alberdi,
2010; Pereira et al., 2013; Yao et al., 2012; Youqiang, Hong, Dao-ming, & Kun-zheng, 2012).
As the impact, the plant's photosynthesis would
be retarded and lead to the suppression of plant
growth and death (Adamski, Peters, Danieloski,
& Bacarin, 2011; Nagajyoti, Lee, & Sreekanth,
2010; Qadir, Schubert, & Steffens, 2013). One
of the symptoms of toxicity in the individual
live plant was chlorosis (Kitao, Lei, Nakamura,
& Koike, 2001). The stunted jabon also showed
this symptom in the present study (Figure 6a).
The difference of macronutrients (except
N) under two contrasting jabon also suggested
that it had a role in the difference of jabon
growth. The soil under jabon B had less toxic
micronutrient; it had more macronutrient than
that under jabon A. This means that the supply
of macronutrient required for plant growth was
relatively more sufficient in the soil under jabon

67

Indonesian Journal of Forestry Research Vol. 8 No. 1, April 2021, 59-72

(a)

ISSN: 2355-7079/E-ISSN: 2406-8195

(b)

Figure 6. Chlorosis symptoms on stunned (a) and good (b) jabon in drained peatland

B than jabon A. Results showed that the less the
micronutrient and the more the macronutrient
was in drained peatland that had a positive effect
on jabon growth. However, it was suggested
that this positive effect could not be sustained
because the growth in all live individuals was
stagnant after 18 MaP, including in jabon that
had relatively good growth in the period from
6 to 12 MaP. Moreover, several of the good
jabon has died at 24 MaP, and some of the
remaining live individuals showed chlorosis
symptoms (Figure 6b).
C. Implication
Our research has not yet proven that jabon
was suitable to be grown in DP in pulpwood
plantation. The research also could not
evaluate the species till harvest time that
commonly is used in pulpwood plantation
(about five years) due to the very high mortality
of jabon. However, the research obtained
some relatively valuable findings from the
relatively short term (till two years). It must be
noticed for the development of the species as
one of the candidates to be grown in DP for
pulpwood plantation. The use of unimproved
seedling was one factor that made unexpected
growth of jabon in DP. Nevertheless, from this
unimproved seedling, the research obtained 7%
jabon, which had promising growth at 24 MaP,
heightened by more than 400 cm (Increment of

68

height >2 m/year). The growth trait in 7% of
jabon could be interpreted as the signal that the
opportunity to obtain improved seed/seedling
that will result in better growth of jabon in DP
is good.
The serious weed-suppressing survival and
growth in the period of 1–2 years indicated
that weed control (weeding) is still needed
at least two years for jabon plantation in DP.
This weeding control (till two years) in rubber
tree and Eucalyptus hybrid has a positive
effect on the growth, thus being used in jabon
plantation (Guzzo, De Carvalho, Giancotti
Alves, Gonçalves, & Martins, 2014; Wirabuana,
Sadono, Juniarso, & Idris, 2020). The negative
effect or toxicity of the excessive Al, Fe and Mn
on survival and growth rates of jabon in DP
indicated that certain treatments are needed to
overcome this serious problem. Some previous
studies on other species showed that this
toxicity could be hindered or at least alleviated
through the application of soil ameliorants
such as lime (CaCO3), silicon (Si) and compost
(Chatzistathis, Alifragis, & Papaioannou, 2015;
Karak, Sonar, Paul, Frankowski, Boruah, Dutta,
& Das, 2015; Prabagar, Hodson, & Evans,
2011; Wu, Shi, Zhu, Wang, & Gong, 2013;
You-qiang, Hong, Dao-ming, & Kun-zheng,
2012). Moreover, the application of arbuscular
mycorrhizal inoculation around the root system
was another treatment that could be chosen

Early Growth of Jabon (Anthocephalus Cadamba Miq) In a Drained Peatland ......(Ahmad Junaedi et al.)

to overcome this toxicity problem (Rouphael,
Cardarelli, & Colla, 2015; Turjaman et al.,
2011). In practice, tree improvement is required
to determine the best seed of jabon with good
growth and tolerance to the DP area. It is also
important to examine which individuals of
jabon are resistant to toxic micronutrients.
IV. CONCLUSION
Our study was the first research that
evaluated the growth performances of jabon in
drained peatland for pulpwood plantation. This
study provided the data of survival and growth
rate of jabon in drained peatland and provided
the soil properties data under jabon stand and
its relationship with growth performance.
These data were valuable for tree selection
as the candidate for pulpwood plantation in
drained peatland (DP). It showed that generally,
jabon had a poor survival rate and growth in
DP due to the use of unimproved seedling, the
weed suppression at the age after 12 MaP and
the metal/micronutrient toxicity Al, Fe and Mn.
However, the study obtained that 7% of jabon
in DP had promising growth at 24 MaP (height
increment >2 m/year); thus, this fact is valuable
to be followed up by a tree improvement
program.
ACKNOWLEDGEMENT
The authors are very grateful to the Research
Institute for Fiber Forest, The Ministry of
Environment and Forestry of Indonesia to
support our research and provide the funding.
Authors are also grateful to Tateng Sasmita,
Syasri Janneta, Sunarto, Arifin, Ramiduk and
Minal Aminin for field assistances and Dodi
Frianto for sharing valuable references and Pak
Saeful Iksan for providing the map of the study
site. We would also like to thank the Research
and Development Division of PT. RAPP for all
valuable support, assistance, accommodation in
the field and the laboratory.

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