IJERD – International Journal of Environmental and Rural Development (2013) 4-1

Research article
erd

Growth Performance of Planted Indigenous Trees 12 years
from Establishment
RUMILA C. BULLECER*
Bohol Island State University, Bohol, Philippines
Email : mslling@yahoo.com

LORETO SOCORIN
Bohol Island State University, Bohol, Philippines
Received 20 December 2012

Accepted 30 January 2013(*Corresponding Author)

Abstract This tree domestication research is an ex-situ conservation effort aimed to findout the growth performance of some indigenous timber species planted outside theirnatural forest habitat in Bohol Island, Central Philippines. Specifically, the study sought tocharacterize the growing conditions of the sites and the biometrics of the trees in threesites   after   12   years   of   growth.   We   also   wanted   to   find   out   the   best   “performers”   when  grown outside the natural forest habitat. Only indigenous trees were used and planted in amixed manner. Most of the planting materials were selected wildlings from the local
forests. A few were brought in from the nearby island of Leyte. Standard biometrics oftrees were taken of all trees. A total of 1,040 trees belonging to 49 species and 25 plantfamilies in 3 land parcels were inventoried. The three sites totaled 2.5 hectares locatedwithin the same village and similar growing conditions. These were typical degraded karst
areas: shallow soils with pebbles and rock outcrops dotting the landscape. Scrubby
vegetation and few scattered trees were the precursor vegetation. The sites used to becogonal for a long time before scrubby vegetation set in. Annual rainfall is about 2,000mm; flat to rolling topography; elevation of 320 meters above sea level. Daytime
temperature ranges from 24-28 degrees Celsius most of the year and 28-33 degrees during
summer (March-May). The standout performers were Terminalia microcarpa, Shorea
contorta, Vatica mangachapui, Shorea palosapis, Parashorea malaanonan, andDracontomelon dao. The biggest Terminalia microcarpa area measured 48 cm in diameterat breast height (dbh). Shorea contorta had a dbh of 29 cm and had a total height of 29
meters. Shorea assamica did not do well in the sites, and was stricken by dieback of
unknown cause. Quisumbing guisok was noted to be very sensitive to moisture stress fromseedling to the sapling stage. At 12 years, many forest-based timbers including
dipterocarps responded well to domestication or ex-situ conservation even in a degradedkarst land in tropical Philippines.
Keywords domestication, indigenous, karst, ex-situ conservation, rainforestation

INTRODUCTION
The Philippines needs an ideal 54% of forest cover to maintain its natural ecological processes.
(Sajise, 1996). Disastrous logging and changing land uses have reduced the original amount of 17
million ha of forested area in the Philippines to 5.5 million ha (18% of total land area) during thelast 40 years. This has also earned notoriety in Southeast Asia as the country with the thinnest
forest cover (Ong, 2004). Less than 6% of the originally 60% of the total forested land area haveremained as prime habitats for wildlife and genetic conservation. Bohol in particular had aremaining natural forest of only 4% from its original full forested area. The island is blessed,
among many other indigenous timbers, some 16 endemic dipterocarp species (Fernando et al,2008).
Among  the  governing  state  policies  of  the  Philippines  is  “to  protect  and  advance  the  right   ofⒸ ISERD

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the  people  to  a  balanced  and  healthful  ecology”  (1987 Philippine Constitution). The latest policy
support at the national level was the issuance of E.O. No. 26 in February of 2011 which launched a
new National Greening Program for the planting of 1.5 billion trees covering about 1.5 million
hectares for a period of six (6) years from 2011 to 2016 in lands of the public domain. The National
Integrated Protected Areas System (NIPAS) Law or Republic Act 7586 mandates that only
indigenous species should be used in the rehabilitation of Philippine watersheds. The maintenanceof sufficient forest cover in Bohol Island is not only ecologically and economically of the utmost
importance but also to keep its banner, nature-based tourism industry alive and productive. For
local policy support, Section 10 of the Revised 2011 Bohol Environmental Code calls for
Boholanos to be self-sufficient in wood needs through tree farming for domestic wood needs, thus
reducing the dependence on commercial fuel as well as to conserve the naturally growing trees.
In support of the national and local policies, and as the leading higher educational institution(HEI) on natural resources management (NRM) in Bohol, Bohol Island State University has longsince taken significant steps to increase its role in biodiversity conservation and poverty reductionin the island -province through in-situ and ex-situ conservation. One of these is the domesticationof forest-based valuable timber species in three sites with a total area of 2.5 hectares which were
established in 1997- 1998 within the land of the University. These were planted with more than 40
tree  species  taken  from  the  island’s  remnant  forests.  Raising  these  trees  in  farms  or  in  homesteads  would ease up the pressure of extraction from their present natural forest habitat and could also
save them from eventual local extinction (Bullecer and Stark, 2002). Part of the domestication
program is to come up with species-site compatibility recommendations for possible wider
community adoption.
OBJECTIVE
The main aim of the study was to find out the domestication potential after more than a decade of
growth of some forest-based tree species in Bohol Island, Philippines. Specifically, it sought tocharacterize the growing conditions of the domestication sites, the biometrics of the trees andidentify the best performers after over decade of growth.
METHODOLOGY
The study sites are located the interior portion of the island- province of Bohol in the central part of
the Philippine archipelago.
Site selection: The domestication sites were in 3 parcels of land, totaling 2.5 hectares, within thesame village and with similar growing conditions. Climatic and elevation data were taken fromexisting secondary data. Edaphic and landscape characteristics were determined by fieldobservation.
Planting stock sources and farm establishment: Wildlings of indigenous trees from nearby
forests were collected and nurtured until they were big enough for field planting. Other seedlings
were obtained from nearby Leyte Island. Adopting the rainforestation technology, the seedlings
were planted in mixed manner, 1.5 to 2.0 meters apart.
Data collection and analysis: A 100% inventory was conducted. Total and merchantable heights
were taken with the use of the Abney hand level and fiber glass tape. Diameter at breast height(dbh) was taken using diameter tape and crown diameter with the fiber glass tape.
Total height was determined by the following formula:
H= tan0 (D) + eye level height(1)0

where H is the height in meters; tan = the angle reading from the eye level mark the stem to thetip of the tree; D = distance from the base of the tree to the spot where the researcher stood.
The merchantable height was measured from the base of the tree up to the portion just before
the heavy branching started. It was obtained using the following formula:Ⓒ ISERD

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H=tan0= (d) + eye level height(2)

where tan0 = the angle reading from the eye level mark to the merchantable top; d = distance fromthe base of the tree to the spot where the researcher stands.
The diameter at breast height was measured at the standard point of 1.3 meters from theground or base. Crown cover or crown area was obtained by getting the average crown diameter of
each tree and calculate the radius there from. Individual crown cover was computed using thefollowing formula:A = ∏ r2

(3)

where, A: crown area, ∏  is the pi (3.1416) and r = radius
Merchantable volume was obtained by making use of the dbh and merchantable height values.
Qualitative description of biometric data was employed in determining the growth performance. No
other statistical analysis was made. Periodical field observations were made on species reactions
during summer or dry conditions.
RESULTS AND DISCUSSION
Biophysical conditions of the tree domestication sites
The domestication sites, with a total land area of 2.5 hectares, were typical degraded karst areas asevidenced by shallow soils and rock outcrops. Soil depth was less than 10 cm in most (about 90%)
areas. After a decade some ground litter began to occupy the ground. The prior vegetationconsisted of scrubby plants, viny thickets and a few scattered mahogany trees at the pole and young
timber stage. The soil texture is silty-clayloam in all three sites. The limestone soils were generally
shallow (less than 10 cm) and slightly alkaline. Annual rainfall is about 2,000 mm; flat to rolling
topography; elevation of 320 meters above sea level. Daytime temperature ranges from 24-28
degrees Celsius most time of the year and 28-33 degrees during summer (March to mid-May).
Species composition and family distribution of the tree domestication farms
Table 1 lists the species at the research sites. A total of 49 species belonging to 25 plant families
were planted in the three land parcels. Dipterocarpaceae was the most represented family with 7
species, followed by Fabaceae, 5 species and Moraceae, 4 species. Most (37%) families had only
one species representative. Two of the species, Vitex parviflora and Artocarpus heterophyllus are
already known to be thriving in open areas or outside natural forest stands.
Overall biometrics of the domesticated indigenous trees
Table 2 shows the overall list of the domesticated species with their corresponding biometrics. A
total of 1,040 individuals belonging to 49 species representing 25 families were inventoried in thethree domestication areas. The domesticated trees have the following biometrics: The trees had amean dbh of 10.8 cm; mean total height of 9.0 m; mean merchantable height of 5.4 m; total
merchantable volume of 47.9 cu m; mean crown diameter of 4.5 m and a total crown area of
11,608.8 sq m or 1.2 hectares. Terminalia microcarpa and Shorea contorta were among the top
performers in diameter and total height growth. The biggest Terminalia microcarpa measured 48
cm in dbh while the biggest Shorea contorta had a dbh of 29 cm and had an impressive total heightof 29 meters. Some 604 dipterocarps consisting of 8 species dominated (58%) the domestication
farms. Myristica philippinenses came second with 50 individuals. The stand of trees in eachdomestication land parcel had provided a good ground cover through its close canopies.

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Table 1 Species composition of the Treedom or Rainforestation ex-situ conservation sites in
Bilar, Bohol, Philippines which were established in 1998-1999
Species
1. Albizia procera
2. Antidesma subolivaceum
3. Artocarpus blancoi
4. Artocarpus heterophyllus
5. Artocarpus nitidus
6. Artocarpus sericicarpus
7. Barringtonia racemosa
8. Bischofia javanica
9. Callophylum blancoi
10. Callophylum inophyllum
11. Cananga odorata
12. Canarium luzonicum
13. Casuarina nodiflora
14.Cinnamomum microphyllum
15. Cynometra ramiflora
16. Diospyros copelandii
17. Diospyros copelandii
18.Discocalyx cymbianthoides
19, Dracontomelon dao
20. Dracontomelon edule
21. Elaeocarpus macranthus
22. Gomphandra luzoniensis
23. Guioa koelreuteria
24. Hopea philippinensis
25. Hopea quisumbingiana

FamilyFabaceae
Euphorbiaceae
Moraceae
Moraceae
Moraceae
Moraceae
Lecythidaceae
Fabaceae
Clusiaceae
Clusiaceae
Anonaceae
Burseraceae
Casuarinaceae
Lauraceae
Caesalpiniaceae
Ebenaceae
Ebenaceae
Myrsinaceae
Anacardiaceae
Anacardiaceae
Elaeocarpaceae
Icacinaceae
Sapindaceae
Dipterocarpaceae
Dipterocarpaceae

Species
26.Horsfieldia megacarpa
27.Intsia bijuga
28.Madhuca Betis
29.Mangifera altissima
30.Myristica philippinensis
31.Ormosia calovensis
32. Parashorea malaanonan
33. Planchonella duclitan
34. Podocarpus rumphii
35.Pometia pinnata forma repanda
36. Pouteria macrantha
37. Pterocarpus indicus
38. Pterocymbium tinctorium
39. Pterospermum celebicum
40. P. diversifolium
41. Pygeum coccineum
42. Shorea assamica
43. Shorea contorta
44. Shorea palosapis
45. Strombosia philippinensis
46. Syzygium brevistylum
47. Terminalia microcarpa
48. Vatica mangachapui
49. Vitex parviflora

FamilyMyristicaceae
Fabaceae
Sapotaceae
Anacardiaceae
Myristicaceae
Fabaceae
Dipterocarpaceae
Sapotaceae
Podocarpaceae
Sapindaceae
Sapotaceae
Fabaceae
Malvaceae
Sterculiaceae
Sterculiaceae
Pittosporaceae
Dipterocarpaceae
Dipterocarpaceae
Dipterocarpaceae
Olacaceae
Myrtaceae
Combretaceae
Dipterocarpaceae
Lamiaceae

A decade of difference and initial impacts
Aside from garnering data and some learning in tree domestication and species potentials forwatershed rehabilitation, the Tree Dom farms had gradually transformed what used to be a
degraded landscape to a wooded land as shown in Fig. 1. In 2004, the provincial ResearchConsortium, where BISU is a member, put up the Bohol Biodiversity Complex (BBC) adjacent to
one of the tree farms for a learning continuum in nurserying and tree farming. The Consortium andthe Complex do biodiversity research, trainings and indigenous tree seedlings production. In thelast 5 years, the Tree Dom farms have been part of the regular alternative ecotourism route in theisland. The tree farms have become a learning area for students, farmers, policy makers,
researchers and other environment advocates from the local, national and international community.
Standouts in domestication and species enrichment
Based on growth performance and general vigor, some of the tested species for domestication havestood out as having domestication potentials. These were Terminalia microcarpa, Shorea contorta,
Vatica mangachapui, Shorea palosapis, Parashorea malaanonan, Dracontomelon dao, Syzygium
brevistylum, Vitex parviflora, Gomphandra luzoniensis, Cinnamomum microphyllum, Callophylum
blancoi and Elaeocarpus macranthus. Except for Shorea assamica, the rest of the plants are
exhibiting acceptable survival and growth rates. The problem with Shorea assamica seems to berelated to fungal infection causing dieback. Hopea quisumbingiana at the seedling and pole stage
seemed very sensitive to moisture stress. In the last three years, Rainforestation Sites 2 and 3 hadbeen enriched with the planting of more dipterocarps and other trees which are endemic to Bohol
island. These are Shorea palosapis, Hopea acuminata, Dipterocarpus kerril, Shorea malibato,Ⓒ ISERD

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Shorea falciferoides and Vatica mangachapui. They were not included in this inventory, yet at thisearly stage, the new additions have manifested promising growth performance.
Table 2 Biometric summary of the planted indigenous timber species at 12 years of age
SpeciesN

Mean
DBH(cm)Albizzia procera (topped off)
Antidesma subolivaceum
Artocarpus blancoi
Artocarpus heterophyllus
Artocarpus nitidus
Artocarpus sericarpus
Barringtonia racemosa
Bischofia javanica
C. inophyllum
Callophylum blancoi
Cananga odorata
Canarium luzonicum
Casuarinas nodiflora
Cinnamomum microphyllum
Cynometra ramiflora
Diospyrus copelandii
Discocalyx cymbianthoides
Dracontomelon dao
Dracontomelon edule
Elaeocarpus macranthus
Gomphandra luzoniensis
Hopea philippinensis
Hopea quisumbingiana
Horsfieldia megacarpa
Instia bijuga
Kamagong-like
Litsea glutinosa
Madhuca betis
Mangifera altissima
Myristica philippinensis
Ormosia calovensis
P. celebicum
Parashorea malaanonan
Planchonella duclitan
Podocarpus rumphii
Pometia pinnata
Pouteria macrantha
Pterocarpus indicus
Pterocymbium tinctorium
Pterospermum diversifolium
Shorea assamica
Shorea contorta
Shorea palosapis
Shorea polysperma
Strombosia philippinensis
Syzygium brevistylum
Terminalia microcarpa
Vatica mangachapui
Vitex parviflora

1
14
7
12
4
23
23
9
27
3
16
3
3
1
5
2
33
1
8
31
148
152
4
5
1
1
1
5
50
1
14
73
3
3
7
1
7
11
13
2
68
100
16
1
3
34
45
45

9.5
11.0
9.5
14.7
11.8
10.3
11.0
16.0
9.0
18.0
19.2
14.3
14.4
5.1
9.7
7.8
15.3
8.5
13.5
10.2
7.1
6.2
16.7
17.2
5.4
10.5
13.4
9.0
8.5
10.5
10.3
7.8
8.9
5.6
13.0
5.7
10.2
10.3
15.5
6
14.6
6.9
5.4
4.1
9.0
21.7
7.1
13.3

4.0
8.6
8.4
9.6
10.3
9.8
7.1
12.0
7.0
14.6
13.4
12.9
6.3
5.4
9.9
5.0
11.0
14.3
10.7
5.3
7.1
6.6
10.4
11.8
5.5
9.4
5.2
8.2
7.2
9
11.6
8.6
9.1
5.5
13.1
9.2
9.5
9.0
15.1
3.2
12.1
6.1
5.3
4.3
11
16.3
7.4
9.0

4.4
6.8
5.2
4.7
3.6
5.7
4.0
4.8
3.7
8.3
6.8
6.0
2.8
5.4
4.6
2.8
6.6
11.4
6.5
5.7
4.5
4.1
4.3
6.8
3.9
4.8
9.3
4.6
4.2
5.9
7.7
4.0
6.7
2.3
8.6
4.8
5.1
5.4
6.7
5.3
8.6
4.3
2.0
6.9
8.1
4.9
4.2

16.8

1,040

10.8

9.0

5.4

Total / Mean

Mean Total Mean Merchantable
Height(m)Height (m)Ⓒ ISERD

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Total Mer.
Volume(m)Mean Crown Total Crown
Diameter (m) Area (sq. m)

2.3

1.8
4.6
7.7
3.2
5.7

12.2
247.8
75.6
272.8
94.7
71.2
397.7
353.2
343.6
60.6
407.9
57.0
15.2
9.1
44.3
20.4
465.2
26.2
231.3
633.3
284.7
89.7
157.5
206.2
9.3
17.1
24.6
68.3
1,836.1
8.6
277.8
22.5
624.1
19.1
184.3
6.7
171.8
241.9
468.1
38.7
216.3
94.2
2.6
8.8
22.0
1,093.6
288.8
1,286.1

47.9

4.5

11,608.8

1.8
0.1
0.8
0.1
1.0
3.0
0.9
0.6
0.7
0.2
0.01

4.4
1.8
0.1

0.3
0.8

2.7
0.7

0.6
0.2
0.7
2.9
4.4

3.9
3.8
3.8
5.8
5.5
4.2
4.0
5.5
3.8
4.6
6.0
7.3
2.6
3.4
3.8
3.6
5.3
5.8
5.1
5.1
3.8
3.0
7.0
10.0
3.4
4.7
5.6
4.0
4.3
3.4
4.7
4.3
2.5
2.8
5.2
2.9
6.2
4.3
6.0
3.1
3.8
3.0

IJERD – International Journal of Environmental and Rural Development (2013) 4-1

Fig. 1 A changed landscape from being a scrubland in 1998 to woodland after a decade
CONCLUSION
Many indigenous forest timbers can be successfully conserved through domestication even indegraded karstic upland environment of Bohol, Central Philippines. Except for two species, the restof the 49 domesticated indigenous timbers studied have adapted very well after 12 years to growing
conditions outside the forest habitat. Some species like Shorea contorta and Terminalia
microcarpa manifest outstanding growth performance than others. Domestication of selected tree
species is imperative especially in regions where communities are heavily dependent on the natural
resource for daily survival.
ACKNOWLEDGEMENTS
1. ViSCA (now Visayas State University) Institute of Tropical Ecology / GTZ - for therainforestation Technology (1996) and for the initial fund assistance in 1998
2. Bohol Island State University - for the support in sustaining the Project
3. Bohol Provincial Government - for the establishment of the Bohol Biodiversity Complex
4. The Bohol Biodiversity Conservation Consortium - for the collaborations in advocacy,training research especially with these Consortium members: Bohol Environmental Management
Office (BEMO) and the Soil and Water Conservation Foundation (SWCF)
5. The Environmental Leadership and Training Initiative [ELTI] - Yale School of Forestry andEnvironmental Studies & Smithsonian Tropical Research Institute for the technical and leadershiptrainings in Rainforestation
REFERENCES
Bullecer, R.C. and Stark, M. 2002. Local knowledge on indigenous trees  in  the  Central  Philippines”.  A  study
conducted under the ICRAF Tree Domestication Program. Summary submitted to ICRAF Southeast
Asia Regional Office, Bogor, Indonesia. 12-14.
Fernando, E.S., Bande, M.J.M., Piollo, R.A., Sopot, D.D., Dolotina, N.E. and Granert, W.G. 2008.
Dipterocarpaceae of Bohol Island, Philippines. Asia Life Sciences Suppl. 4.
Ong, P. 2010. State of Philippine biodiversity: Changing mindscapes amidst the crisis.
Sajise, P. 1996. Sustainable agriculture in the marginal uplands of Southeast Asia. Bohol Environmental
Code (2011 edition) .Philippine Constitution. (1987. Article II, Sec. 16.RA 7586. The NIPAS Law of1991).

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