4. Decky (Exotic).cdr

BIOTROPIA Vol. 21 No. 1, 2014: 38 - 52

EXOTIC PLANTS IN HALIMUN SALAK
CORRIDOR:MICRO-ENVIRONMENT,

DETECTION AND RISK ANALYSIS
OF INVASIVE PLANTS

DECKY INDRAWAN JUNAEDI , DODO

Received 18 June 2013/Accepted 2 June 2014

Research of exotic plant species detection and risk analysis of invasive plant was
conducted in Halimun-Salak corridor area. This study aimed to conduct inventory of exotic
plant species in this area and to perform risk analysis of invasive to the exotic plants found. The
invasion risk assessment of detected exotic plants was analyzed using Weed Risk Assessment
Procedure (WRAP) method. Moreover, analysis of multi-dimensional scaling (MDS) based
on inequality was performed on relative humidity, light intensity, and soil pH. There are
eleven exotic plant species consisted of three tree species and eight species of herbs/shrubs.

and are the exotic species with the highest and the
lowest WRAP score, respectively. MDS analysis shows that exotic tree species have similar
environmental variables. Moreover, environmental variables of are relatively
different from other exotic species found in the Halimun-Salak corridor.

Recommendations for the management of invasive exotic plant species in the area are:
immediate management implementation, priority of eradication to exotic plants that have not
been abundant but have high risk score, two management options (gradual eradication or
containment) should be considered for exotic plants with very high WRAP score, such as

and .

plant ecology, Halimun-Salak corridor, Multi-Dimensional Scaling, Weed Risk
Assessment, invasive plant, conservation

1 2

Cibodas Botanical Garden, Indonesian Institute of Sciences (LIPI),
PO. BOX 19 SDL Sindanglaya, Cipanas, Cianjur 43253,

Centre for Plant Conservation, Bogor Botanical Garden, Indonesian Institute of Sciences (LIPI)

Austroeupatorium inulifolium Camellia sinensis

Clidemia hirta

Ageratina riparia, Austroeupatorium inulifolium Chromolaena odorata

ABSTRACT

Key words:

* Corresponding author : deqee82@gmail.com

DOI: 10.11598/btb.2014.21.1.4

INTRODUCTION

Halimun-Salak corridor ecosystem is important because it is not only a mountain
forest ecosystem, but also acts as a connecting corridor between Mount Salak and
Mount Halimun. Moreover, Halimun-Salak corridor has several risk factors associated
with the threat to ecosystem integrity. Along with habitat degradation, fragmentation
and disturbance from human activities, invasive alien species (IAS) (including invasive
alien plants) being one of the factors that poses a threat to the integrity of the
Halimun-Salak corridor ecosystem (JICA 2005). Within an 11 years period (1990-
2001), the width of the Halimun-Salak corridor has decreased from 1.4 km (1990) to
0.7 km (2001) (Cahyadi 2003). On the other hand, there are lack of studies on invasive
species in South East Asia, where the biodiversity hotspot lies in (Peh 2010).

Considering invasive species issues, detection and risk analysis of invasive plants
are needed in the management of invasive plants. Upon the detection, alien species
which potentially become invasive could be detected and managed earlier so that
management cost becomes cheaper. By doing risk assessment, existed exotic plants,
either invasive or not invasive can be estimated and ranked due to its invasiveness rates
or invasiveness possibilities. Therefore, management prioritization of exotic invasive
plants will be accomplished easier with risk assessment. Risk assessment reflects the
chances of an exotic species to become invasive in the future or reflects the rate of
invasiveness itself. Weed Risk Assessment Procedure (WRAP) (Virtue 2008) is a
risk assessment system used to assess the risk of invasive plant species from an exotic
species that are already existed in a new host area.

The objective of this study was to conduct inventory of exotic plants (either
invasive or not invasive (yet)) that are already existed in the Halimun-Salak corridor.
This study also aimed to look at the risk of exotic plants to become invasive in the
Halimun-Salak corridor. In addition, this study also aimed to analyze the diversity of
habitat environment (micro-environment) variables (pH, light intensity and air
humidity) of areas where exotic species were detected.

Halimun-Salak corridor is the area that connects Mount Salak and Mount
Halimun. Halimun-Salak corridor included as a part of Halimun-Salak National Park
based on Minister of Forestry Decree No. 175/Kpts-II/2003 dated June 10, 2003.
Northern part of the corridor is part of administrative region of Bogor covering area
as large as 1662.72 hectares. Southern part of the corridor is included in the district of
Sukabumi which covered 2533 hectares. The altitude range of Halimun-Salak corridor
is from 1000 m above sea level to 1400 m above sea level. Annual rainfall in the
Halimun-Salak corridor ranges from 4000 mm to 5000 mm per year (JICA 2005).

et al.

MATERIALS AND METHODS

Study site

Exotic Plants in Halimun Salak Corridor Decky Indrawan Junaedi– et al.

Exotic plants detection

Exotic species inventory was conducted at 27 observation points in 7 different
locations in the Halimun-Salak corridor. Sampling areas covered by the detection
sampling are: Bivak, Legok Buluh, Cigorowek-3, Palahlar, Pasir Panjang, Pasir Bedil
and Kubang (Table 1).

Tabel 1. Detection sampling location in Halimun-Salak corridor

Location
Coordinates Altitude

(m asl)
Sampling
number

AR/FI
S E

Bivak 06044'59.8" 106036'47.9" 1100 6 AR and FI

Legok Buluh 06044'53.0" 106037'07.0" 1068 6 AR and FI

Cigorowek-3 06044'42.1" 106038'01.3" 1015 4 AR and FI

Palahlar 06044'53.1" 106037'22.6" 1021 2 AR

Pasir Panjang 06045'11.2" 106037'12.6" 1061 3 AR and FI

Pasir Bedil 06045'06.9" 106036'54.6" 1069 2 AR

Kubang 06045'17.6" 106037'52.2" 1042 4 AR and FI

Notes: AR= adjacent to footpath, FI= forest interior

Detection samplings were conducted in two types of locations. The first location
type is the area adjacent to forest access road into the woods with the assumption that
the exotic species introduction pathway is via humans (carried away to the forest by
humans). The second location type is the area inside the forest interior with the
assumption that in addition to human pathways, exotic species can also be dispersed by
the help of animals, wind and other vectors.

At each sampling point, exploratory observation of the exotic plant species was
conducted within a radius of 3 meters from the point of observation. Exotic plant
species were observed and recorded.

Invasiveness risk assessment

Exotic plants that have been detected were then assessed by using Australia Weed
Risk Assessment Procedure (WRAP) (Virtue 2008) to assess the risk of
invasiveness. WRAP is a framework used to analyze the risk of an invasive exotic plant
that are already existed in an invaded area. WRAP consists of questions that should be
answered and then scoring was performed based on the answers. The scoring decision
was conducted fully based on available scientific information provided from online
global invasive plant database such as Pacific Island Ecosystem at Risk (PIER) and
Invasive Species Specialist Group (ISSG), IUCN database. Total accumulated value of
all WRAP scoring answer was expressed as a risk score. The risk scores are quantitative
and can be compared between one species and another in the analysis. WRAP used in
this study were adapted and modified to match the conditions and circumstances in

et al.

BIOTROPIA Vol. 21 No. 1, 2014

the study locations as provided in Annex 1. Accuracy of the risk assessment results is
measured using logistic regression analysis to generate the ROC curve (receiver
operating characteristic, using MYSYSTAT 13) that describes how accurate risk
analysis model used (Quinn & Keough 2002). Logistic regression follows the
equation:

e / (1 + e )...........................................................................................................1)

whe P score)
ants obtained (real data) was

defined as the relative frequency (FR) more than 10%.

On every detection sampling plot, ecological (micro-environment) data were
recorded for analysis of ecological habitats. Habitat ecological data recorded include:
air relative humidity, light intensity, and soil pH. Analysis of multi-dimensional scaling
(MDS) was based on inequality using XLSTAT software (Microsoft Excel add-in) and
was conducted based n micro-environment data. MDS analysis was used to examine
the degree of differences among detected exotic species based on its micro-
environment/ micro-habitat variables measured.

Based on the sampling detection of exotic plants in 27 locations of the study site,
species area curve is presented in Figure 1. The curve indicates the relation between the
numbers of sampling plots which was taken with the addition of new exotic species
detected.

Π (x) =

re: g (x) = β0 + β1 (WRA and Π (x) is the opportunity of exotic species (i)
will become invasive. Definition of invasive exotic pl

g (x) g (x)

Micro-environment

RESULTS AND DISCUSSION

Detected exotic plants in the Halimun-Salak corridor based on modified WRAP
scoring results are presented in Table 2.

Figure 1. Species-sampling relation curve that describes the relation between the number
of sampling (x axis) and new exotic species counted (y axis)

Exotic Plants in Halimun Salak Corridor Decky Indrawan Junaedi– et al.

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BIOTROPIA Vol. 21 No. 1, 2014

ROC curves that illustrate the accuracy of the risk analysis model are presented in
Figure 2. The value of area under the ROC curve is 0.817.This value showed that the
accuracy of the logistic regression model is approximately 81.7%

Figure 2. ROC ( ) curve that determines the accuracy of the
logistic regression conducted in the risk assessment

receiver operating characteristic

Figure 3. MDS configuration of three environment variables of detected exotic plants: soil
pH, light intensity and air humidity. Dimension 2 was used in the configuration.
Detected exotic species are, AI: , BP: , CC:

, CO: , CH: , LC: ,
ME: and SA:

Austroeupatorium inulifolium Bellucia pentamera
Calliandra calothyrsus Chromolaena odorata Clidemia hirta Lantana camara

Maesopsis eminii Spermacoce alata

Exotic Plants in Halimun Salak Corridor Decky Indrawan Junaedi– et al.

MDS analysis results based on three environmental variables (pH, light intensity
and air humidity) are presented in Figure 3. Kruskal stress value of 0.002 indicates that
the model configuration presented in Figure 3 is valid. The valid Kruskal stress value is
smaller than 0.1 (Quinn & Keough 2002).

Shepard diagram of MDS analysis is presented in Figure 4. Shepard diagram
indicates the reliability of the data used in the MDS analysis.

Based on the detection results, from totally 11 exotic species detected, four of
them are tree species: , , and

. The rest of other seven species are herbaceous/shrubs. Based on
detection sampling data, two exotic tree species having FR value above 10% are

and . is native to South America
(Backer & Backhuizen 1963). This plant is likely to spread rapidly in the Halimun-
Salak corridor because of rapid spread through the animal's assistance that eats the
fruit.

Exotic species can become invasive when it got past the “barrier” that exists in the
invaded locations (Theoharides & Dukes 2007). In general, exotic plants have
become invasive when it is said to have had offspring and form new colonies that are
relatively numerous and have an adverse impact to invaded ecosystems (Richardson

2000). However, not all exotic species detected are able to reach interior part of the
forest where the forest canopy cover is still relatively intact. Most of the exotic plants
of the Asteraceae found in the exterior forest areas or in the forest gaps (forest
openings). MDS analysis showed that two Asteraceae species ( and

) have different positions relative to the other exotic species due to different
types that formed on the configuration. The different position in the MDS

Maesopsis eminii Cinchona pubescens Calliandra calothyrsus
Bellucia pentamera

Bellucia pentamera Calliandra calothyrsus Bellucia pentamera

et
al.

C. odorata A.
inulifolium

Figure 4. Shepard diagram of MDS analysis of three environment variables: soil pH,
light intensity and air humidity

BIOTROPIA Vol. 21 No. 1, 2014

configuration refers to different micro-environment preferences. Therefore,
and have relatively different micro-environment preferences compared
to other exotic plants that are clustered in different quadrants (Fig. 3). Even though

has the highest WRAP value and refers to high risk to become invasive, but
the environmental constraints (the intensity of light/canopy shade availability)
becomes the limiting factor for these two species to become very invasive. However, if
there is a gap occurred in the forest area, this species will be able to establish and
invade.

Another interesting point is the grouping of exotic tree species in the same
quadrant of the MDS analysis result ( and

) (Fig. 3). Habitat preference (relative humidity, light intensity, and soil pH)
were similar among these three exotic tree species in Halimun-Salak corridor. These
three exotic tree species were mostly found in the interior forest, not in the forest
edges. Indeed, these three exotic tree species have not reached invasive stage.
However, after a period of adaptation time (lag time), these species will quickly
become invasive and will have an impact on the Halimun-Salak corridor ecosystem.
Time lag determines exotic plant species to become invasive (Hobbs & Humpries
1995). IAS management in Halimun-Salak corridor should be focused on species that
are already existed in the forest interior. Effective and efficient management can
minimize the cost of subsequent management (Radosevich 2007).

's micro-environment preference (three variables: soil pH, light
intensity and relative humidity) is very different from almost all exotic species
recorded. Backer and Backhuizen (1963) mentioned that naturalized in West
Java, especially around Bogor. In its native range in South America and the Caribbean,

dominates open areas, forest edges and forest openings/ disturbed forest and
is rarely found under the shade-covered forests floor (DeWalt ., 2004). But DeWalt

. (2004) also have indicated that is more shade tolerant in the invasion
region than in the native range. included as one of the 100 worst invasive
species in the world (ISSG 2006).

and is an interesting case in this study. WRAP values
of and are relatively high, while the results of the detection
sampling populations is relatively low (Table 2). There are several factors that may
explain the low number of sampling populations of and . First, the
number of sampling may be relatively small compared to the pattern of spread of this
species in the Halimun-Salak corridor. With the equal number of sampling units, the
representation of the types of populations obtained with the clumped distribution
pattern is more adequate than diffuse or random dispersal patterns. Secondly,

is not (or not yet?) penetrating the ecological constraints that exist in the
Halimun-Salak corridor forest to reach the invasive stage. is still in the
process of establishment/early naturalization stage. naturally occurs in
open areas and the seed germination is inhibited by low light intensity (Gentle & Duin
1997, 1998).

C. odorata
A. inulifolium

A.
inulifolium

Maesopsis eminii, Calliandra calothyrsus Bellucia
pentamera

Clidemia hirta

C. hirta

C. hirta
et al

et al C. hirta
C. hirta

Ageratina riparia Lantana camara
A. riparia L. camara

A. riparia L. camara

L.
camara

L. camara
L. camara

Exotic Plants in Halimun Salak Corridor Decky Indrawan Junaedi– et al.

CONCLUSIONS

ACKNOWLEDGEMENTS

REFERENCES

There are 11 species of exotic plants in the Halimun-Salak corridor area consisted
of three woody tree species and eight herbs/shrubs species. is an
exotic species that has the largest WRAP value (24) and is an exotic
species with the lowest WRAP value (-4). Exotic tree species have similar
environmental preferences. is an exotic species that has relatively
different environment variables compared to other exotic species found in the
Halimun-Salak corridor.

Based on the risk assessment of invasiveness and field observation conducted,
some recommendations for the management of invasive exotic plant species in the
Halimun-Salak corridor are: (1) management of invasive species can be done with
several options, but the more immediate the implementation, the cheaper the
management cost and the simpler the management methods will be, (2) eradication
can be implemented to exotic plant species that have not been abundant in population
but have relatively high WRAP value such as and .
Whenever possible, eradication should start from the individual which exist in the
forest interior and continue toward the outside of the forest, (3) Gradual eradication
or control (containment) are two possible management options for exotic plant
species that have a very high WRAP score such as ,
and .

Future study should be focused on how to conduct IAS management
implementation that gives the smallest impact to the ecosystem of Halimun-Salak
corridor. It is important to conduct ecological study of exotic species micro-habitat as
well as investigating the impact of these exotic species to Halimun-Salak corridor
ecosystem.

Authors thank Soekisman Tjitrosoedirdjo for significant recommendations and
review on the methodology section of this work. Authors also thank Sri Astutik for
valuable discussion during field data collection, Megawati for dedicated plant
identification and to Pak Uci and Pak Atma for their field assistance and guidance.
This study funded by grant “Program Prioritas Nasional 9 Program Penelitian,
Penguasaan, dan Pemanfaatan Iptek: Pembangunan Kebun Raya Daerah” (National
Priority Program, 9 Programs for Research, Control, and Utilization of Science and
Technology on the Development of District Botanical Garden).

Lantana camara
Camellia sinensis

Clidemia hirta

Bellucia pentamera Cinchona pubescens

Ageratina riparia Chromolaena odorata
Lantana camara

Backer CA, Backhuizen RCVDB. 1963. Flora of Java (Spermatophytes only) volume I. Groningen: N.V.P.
Nordhoff.

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Cahyadi I. 2003. Analisis Spasial Struktur dan Fungsi Koridor Hutan antara Taman Nasional Gunung Halimun
dengan Hutan Lindung Gunung Salak. Bogor: Program Pascasarjana IPB, Tesis.

DeWalt SJ, Denslow JS, Ickes K. 2004. Natural-enemy release facilitates habitat expansion of the tropical shrub
. Ecology 85(2): 471-483.

Gentle CB, Duggin JA. 1997. L. invasions in dry rainforest - open forest ecotones: The role of
disturbances associated with fire and cattle grazing. Australian Journal of Ecology 22: 298-306.

Gentle CB, Duggin JA. 1998. Interference of by with nutrient enrichment in
mesic forests on the Central Coast of NSW. Plant Ecology 136: 205-211.

Heikkila J. 2011. A review of risk prioritisation schemes of pathogens, pests and weeds: principles and practices.
Agricultural and Food Science 20: 15-28.

Hobbs RJ, Humphries SE. 1995. An integrated approach to the ecology and management of plant invasions.
Conservation Biology 9: 761-770.

Invasive Species Specialist Group (ISSG). 2006. Global Species Invasive Database: Clidemia hirta. Accessed 10
January 2013 from

JICA Team, Endangered Species. 2005 Ecological Study Halimun-Salak Corridor Mount Halimun-Salak
National Park. Accessed 10 September 2011 from .

Peh KSH. 2010. Invasive species in Southeast Asia: the knowledge so far. Biodiversity and Conservation 19: 1083-
1099.

Quinn GP, Keough, MJ. 2002. Experimental Design and Data Analysis for Biologist. Cambridge: Cambridge
University Press.

Richardson DM, Pysek P, Rejmanek M, Barbour MG, Panetta FD, West, CJ. 2000. Naturalization and invasion of
alien plants: concepts and definitions. Diversity and Distributions 6: 93-107.

Radosevich, SR 2007, Plant invasions and their management, chapter 3 in CIPM (ed.), Invasive plant
management: CIPM online textbook, Bozeman, MT: Center for Invasive Plant Management. Accessed
2 May 2011 from .

Theoharides KA, Dukes JS. 2007. Plant invasion across space and time: factors affecting nonindigenous species
success during four stages of invasion. New Phytologist 176: 256-273.

Virtue S, Spencer, RD, Weiss, JE, Reichard, SE. 2008. Australia's Botanic Gardens weed risk assessment
procedure. Plant Protection Quarterly 23: 166-178.

Clidemia hirta

Lantana camara

Choricarpia leptopetala Lantana camara

http://www.issg.org/database/species/ecology.asp?si=53&fr=1&sts=sss& lang
=EN.

http://sci.kagoshima-u.ac.jp

http://www.weedcenter.org/textbook/index.html

Exotic Plants in Halimun Salak Corridor Decky Indrawan Junaedi– et al.

Annex 1. Modified Weed Risk Assessment Procedure used in the study (Virtue
2008)et al

IMPACTS SCORE

1. WEED HISTORY – What is the weed history of the plant?

It is a weed in your region 4

It is a weed elsewhere in Indonesia 3

It is a weed overseas 2
It is not known to be weedy, but other forms of the plant and/or plants in the same
genus are weeds in Indonesia and/or overseas 1

The genus is not known to be weedy 0

2. COMPETITION – How well does the plant out-compete other types of plants?

If not controlled it can grow to dominate the following three size classes of plants: 4

trees (or emergent aquatics)

shrubs (or surface aquatics)

ground covers (or submerged aquatics)

If not controlled, it can grow to dominate one of the above size classes of plants. OR 2

at certain times of the year it can dominate two size classes
If not controlled, it can dominate one of the above size classes at certain times of the
year 1
It is not competitive, and is readily dominated by most other plants if they are not
controlled 0

3. HEALTH – Is the plant a health risk to people and/or animals?

Is it highly toxic and has caused deaths 3

It can cause significant physical injuries or illness 2

It can cause slight physical injury or mild illness with no long-lasting effects 1

It is not a health risk to animals or humans 0

4. MOVEMENT – If the plant escapes does it have the potential to block the movement
of people, animals, vehicles or water?

A group of plants is very tall, thorny, tangled and/or dense & impenetrable year-long 3
A group of plants is rarely impenetrable, but does significantly undergo slow physical
movement year-long 2
A group of plants is never impenetrable but can significantly undergo slow movement
for part of the year 1

Plant has no significant effect on movement 0

BIOTROPIA Vol. 21 No. 1, 2014

IMPACTS SCORE
5. ENVIRONMENTAL EFFECTS – Does the plant have attributes that, at high density, can

cause detrimental changes to the environment?

The plant has two or more of the following attributes: 2

highly flammable leaves fixes nitrogen
salty leaves habitat or food source for pest
animal invasion

high water use

removes habitat or food source for native animals

It has one of the above attributes 1

It has none of the above attributes 0

6. EASE OF CONTROL - How easy is the plant to kill?
Hard. It readily tolerates or reshoots after herbicide application, cutting, cultivation, grazing or
fire 3

Medium. One herbicide application or cultivation kills the plant, but not cutting, grazing or fire 2

Simple. Plants are killed by hand-pulling, cutting, grazing or fire 1

POTENTIAL DISTRIBUTION

7. HARDINESS – How well is the plant adapted to the local climate?
In the garden it needs no maintenance to establish, grow and flower, if planted at the right time
of year. The localclimate is similar to other places where it grows in the world. OR, it is a weed
of drier, exposed land in the region or in other parts of Indonesia or overseas with similar
climate types

It needs some maintenance to establish when planted in the garden, but will then grow and
flower well without further maintenance. The local climate is harsher in some aspects to what
the plant is originally adapted to. OR, it is a weed of wetter, sheltered land in the region or in
other parts of Indonesia or overseas with similar climate types

It needs some maintenance to establish when planted in the garden, but can then survive
unassisted. However, it grows poorly in the local climate and needs occasional maintenance
during stressful periods (e.g. watering in dry months). OR, it has naturalised occasionally in the
region in specialist habitats (i.e. it has a narrow ecological amplitude) but hasn’t formed
high-density infestations. It grows in distinctly different climates elsewhere in Indonesia or
overseas

It needs frequent maintenance and/or special conditions to grow and flower in the garden. OR,
the local climate isvery different to where the plant grows elsewhere in the world and it has not
been recorded as naturalised in the region or in other parts of Indonesia or overseas with similar
climate types

Annex 1. Continued

Exotic Plants in Halimun Salak Corridor Decky Indrawan Junaedi– et al.

Annex 1. Continued

INVASIVENESS

8. REPRODUCTION – How well does the plant reproduce?

The plant has all three of the following attributes: 4
short time to seeding (within 3 years from planting for herbaceous plants, 5 years for
woody plants)

‘volunteer’ seedlings commonly come up in the garden, OR as a weed,

seedlings are commonly seen nearby mature plants.

mature plants produce at least 5 new plants by vegetative means per year

It has two of the above attributes 3

It has one of the above attributes 2

It has none of the above attributes, but is able to reproduce by itself 1
It sets no seed in any natural circumstances and has no vegetative spread. The plant can only be
propagated with human assistance (eg. shoot cuttings). It will not naturalise. (LOW WEED
RISK)

9. NATURAL SPREAD – Are the plant’s propagules (seed or vegetative) likely to spread long
distances to susceptible habitats by natural means?

Propagules are likely to be dispersed by two or more of the following: 4

flying animals ground animals water wind

AND susceptible habitats (e.g., farmland, native vegetation, road and rail corridors, waterways)
are within 1 km of the gardens

Propagules are likely to be dispersed by two or more of the above means AND susceptible
habitats are within 5 km of the gardens, OR, Propagules are likely to be dispersed by one of
the above means AND susceptible habitats are within 1 km of the gardens

Propagules are likely to be dispersed by one of the above means AND susceptible habitats are
within 5 km of the gardens 2
Propagules are not normally spread long distances from parent plants BUT the Botanical
Garden abuts susceptible habitats 1
Propagules are not normally spread long distances from parent plants and the Botanical
Garden is from susceptible habitats by urban developmentbuffered 1

10. HUMAN SPREAD – Are the plant’s propagules (seed or vegetative) likely to spread long
distances due to human activities?

The plant is appealing and easily to propagate. Visitors to the gardens may intentionally take
propagules (e.g., seeds, cuttings, fruit etc.) to grow elsewhere 3

Propagules are likely (or known) to be dispersed by two or more of the following means: 2

people (accidentally) vehicles/machinery

contaminated produce in soil

Propagules are likely (or known) to be dispersed by one of the above means 1

Propagules are not normally spread long distances from the parent plant 0

SCORE

LWR

BIOTROPIA Vol. 21 No. 1, 2014

Annex 2. Detection sampling data from 27 plots.

Date
plot

number species name
Altitude
(m asl)

soil
pH

air relative
humidity

(%)

light
intensity (X

2000 lux)

20/06/2012 1 Austroeupatorium inulifolium 1110 6 50 322

2 Austroeupatorium inulifolium 1103 6.2 55 219

3 Austroeupatorium inulifolium 1100 6.8 56 1270

4 Austroeupatorium inulifolium 1100 6.8 56 1270

Calliandra callothyrsus

5 Calliandra callothyrsus

Austroeupatorium inulifolium

6 Bellucia pentamera

21/06/2012 7 Austroeupatorium inulifolium 1050 6 43 62

Bellucia pentamera

8 Spermacoce alata 1068 6.8 52 594

Austroeupatorium inulifolium

Bellucia pentamera

9 Austroeupatorium inulifolium 1019 6.5 47 364

Calliandra callothyrsus

10 Maesopsis eminii 1056 6 51 433

Maesopsis eminii

12 Austroeupatorium inulifolium 1099 6.8 37 1010

Spermacoce alata

Maesopsis eminii

Bellucia pentamera

Austroeupatorium inulifolium

23/06/2012 13 Chromolaena odorata 1046 6 49 209

Bellucia pentamera

14 Bellucia pentamera 1014 6.2 49 219

Calliandra callothyrsus

15 Calliandra callothyrsus 1041 6 51 697

Bellucia pentamera

16 none 1003 6.5 55 267

24/06/2012 17 Austroeupatorium inulifolium 1005 6.5 50 3390

Chromolaena odorata

Bellucia pentamera

18 Austroeupatorium inulifolium 1049 6 51 1627

Lantana camara

Clidemia hirta

Exotic Plants in Halimun Salak Corridor Decky Indrawan Junaedi– et al.

Date
plot

number species name
Altitude
(m asl)

soil
pH

air relative
humidity

(%)

light
intensity (X

2000 lux)

Chromolaena odorata

Spermacoce alata

25/06/2012 19 Lantana camara 1036 6.2 57 90

Clidemia hirta

Spermacoce alata

Austroeupatorium inulifolium

Chromolaena odorata

20 Cinchona succirubra 1028 6.5 57 8.6

Bellucia pentamera

21 Austroeupatorium inulifolium 1010 6 58 6.1

Chromolaena odorata

Bellucia pentamera

26/06/2012 22 Austroeupatorium inulifolium 1061 6 47 29

Calliandra callothyrsus

Clidemia hirta

Chromolaena odorata

Spermacoce alata

23 Austroeupatorium inulifolium 1020 6.4 50 1311

Clidemia hirta

Bellucia pentamera

27/06/2012 24 Calliandra callothyrsus 1028 6.8 45 1590

Austroeupatorium inulifolium

Camellia sinensis

Clidemia hirta

Spermacoce alata

Chromolaena odorata

25 Maesopsis eminii

Austroeupatorium inulifolium

Clidemia hirta

26 Calliandra callothyrsus 1028 6.8 45 1590

Clidemia hirta

27 Austroeupatorium inulifolium 1028 6.8 45 1590

Calliandra callothyrsus

Clidemia hirta

Chromolaena odorata

Ageratina riparia

Annex 2. Continued

BIOTROPIA Vol. 21 No. 1, 2014