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492 International Forestry Review Vol.14(4), 2012
Developing establishment guidelines for Shorea palosapis
in smallholder plantings in the Philippines
N.O. GREGORIO
1
, J.L. HERBOHN
1
and J.K. VANCLAY
2
1
The University of Queensland, St Lucia, QLD 4072, Australia
2
Forest Research Centre, Southern Cross University, Lismore NSW 2480, Australia
Email: no.gregorio@gmail.com
SUMMARY
A series of trials examining fertilizer-shading interactions on the island of Leyte (Philippines, 11°N) revealed that the endemic dipterocarp
mayapis (Shorea palosapis) benefits from shade trees, either directly above or to the east, during the early stages of plantation establishment.
Although it can attain 2 cm/year diameter increment in plantations, mayapis exhibits poor growth and survival under wide spacing, when
waterlogged and in exposed bare soil. Indications that early growth can be hampered by high soil temperatures warrant further research and
development of practical planting techniques for smallholders.
Keywords: establishment, endemic tree species, fertilizer-shade interaction, nurse crop
Développement de lignes de conduite pour l’établissement du Shorea palosapis dans des
petites plantations des Philippines
N.O. GREGORIO, J.L. HERBOHN et J.K. VANCLAY
Une série d’essais examinant les interactions engrais/ombre sur l’île de Leyte (Philippines, 11 degrés N) a révélé que le dipterocarp mayapis
(Shorea palosapis) endémique profite des arbres offrant un ombrage, directement au dessus ou vers l’est, pendant les premiers stades de son
établissement en plantation. Bien qu’il puisse atteindre des croissances de diamètre de 2 cm/an dans les plantations, le mayapis connait maigre
croissance et survie quant il est trop espacé, noyé ou exposé sur la terre nue. Des indications que la croissance initiale peut être empêchée par
des fortes températures du sol encouragent une recherche plus poussée et un développement de techniques pratiques de plantation pour les
petits exploitants.
Elaboración de directrices para el establecimiento de Shorea palosapis en plantaciones de
pequeños propietarios de Filipinas
N.O. GREGORIO, J.L. HERBOHN y J.K. VANCLAY
Una serie de ensayos que examinaron las interacciones entre sombreado y fertilizante en la isla de Leyte (Filipinas, 11°N), revelaron que
durante las etapas iniciales del establecimiento de la plantación, la dipterocarpácea endémica mayapis (Shorea palosapis) se beneficia de la
presencia de árboles de sombra, ya sea directamente por encima o bien localizada al este. Aunque incremento diamétrico en plantaciones puede
alcanzar los 2 cm/año, mayapis muestra un crecimiento y una supervivencia pobres bajo espaciamientos amplios, así como en los suelos
anegados o los desnudos y expuestos. Ciertos indicios de que el crecimiento inicial puede verse obstaculizado por altas temperaturas del suelo
merecen investigación adicional y el desarrollo de técnicas de plantación prácticas para pequeños propietarios.
Developing establishment guidelines for Shorea palosapis 493
dipterocarps, viable for 3–7 days after collection, so most
plantings rely on wildlings. Paler and Alcober (1991) and
Zabala (1993) reported some success with rooted cuttings,
but these techniques have not yet been operationalized. In his
review of dipterocarp plantations, Weinland (1998) recog-
nised the challenges of effective establishment, and called for
“controlled (artificial) experiments . . . for base line informa-
tion on the light requirements of species to be complemented
by field trials where shade from natural vegetation is manipu-
lated”. Our trials (Gregorio et al. 2009) address this question,
and seek to inform future reforestation efforts with this
species, specifically with regard to establishment procedures.
Some guides advocate that mayapis “can be planted
directly in open areas” (Visayas State University c.1995) and
is “pioneer-like, least susceptible to drought and performing
best in open areas” (Marohn 2008), whilst others recommend
it as a shade-loving tree that should be planted during the
second year of a rainforestation effort (Margraf and Milan
1996). Otsamo (1998) recommended Paraserianthes falca-
taria as a nurse tree to assist establishment of “fast-growing
plantations on Imperata grasslands using dipterocarps with
wide ecological tolerance”. It has long been observed that
shade can improve the nutrient balance in tree seedlings
(Bevege and Richards 1970), and this concept is applied
commercially with agroforestry coffee typically grown under
shade with minimal fertilizer input, whilst industrial coffee
tends to be grown in full sun with fertilizer and irrigation
(DaMatta et al. 2007). In this study, we explore the utility of
both artificial shade and nurse trees in facilitating plantation
establishment.
Bruzon (1978) reported that potted mayapis grew better
with fertilizer, and recommended 1–2g NPK per seedling, but
others have shown that fertilizer may have no effect, or may
even be detrimental to Shorea seedlings if it interferes with
ectomycorrhizae (e.g., Turner et al. 1993). Our study includes
fertilizer applications to provide preliminary guidance for
plantation establishment.
METHODS
A series of trials was established at Leyte Leyte (11°N 124°E,
Figure 1) to explore several aspects of the silviculture of
mayapis (Shorea palosapis) and its interactions with three
other species of interest to smallholders (narra, Pterocarpus
indicus; falcata, Paraserianthes falcataria; mahogany,
Swietenia macrophylla). These species were chosen to evalu-
ate well-documented synergies between nitrogen-fixing and
other species (Forrester et al. 2006) in both native and exotic
species. Two trials employed clinal designs (Vanclay et al.
1995, Vanclay 2006a) to investigate specific responses to a
wide range of spacing and species composition, and these
offer some insights into early growth of mayapis. A third trial
specifically examined shade and fertilizer responses of maya-
pis, in an attempt to resolve contradictions observed in the
literature. The experiments were established in 1.2 ha of for-
mer pasture land in the municipality of Leyte in Leyte Island,
Philippines. Figure 2 shows the location of the study site and
INTRODUCTION
During the past decade, the Philippine government’s policies
on forest management have shifted from a focus on large-
scale, timber-oriented industrial forestry to multiple-product,
people-oriented small-scale tree farming (Mangaoang 2002).
Small-scale forestry has been promoted as an effective
approach to solve the widespread loss of forest, promising
poverty alleviation while increasing environmental protec-
tion. It is envisaged that smallholder tree crops can benefit the
rural economy (Nichols and Vanclay 2012) and ensure the
supply of plantation timber (Dy and Bautista 1999, Guiang
2001). However, previous research undertaken in Leyte
Island indicates that only about 30% of the potential timber
yield is being realized by smallholder tree farmers (Herbohn
et al. 2009a). Lack of appropriate silviculture, inadequate
site-species matching and inferior germplasm contribute
to low financial returns from smallholder tree plantations
(Herbohn et al. 2009b). This study forms part of a larger
project that addresses these issues (Herbohn and Harrison
2005).
Existing tree farms on Leyte Island comprise almost
entirely two exotic species – gmelina (Gmelina arborea) and
mahogany (Swietenia macrophylla) (Herbohn et al. 2009a).
These species were widely planted during the National Fores-
tation Program (NFP) of the Department of Environment and
Natural Resources (DENR) during the 1990s (Harrison et al.
2004). Although these exotics dominate most tree farms
and reforestation projects, some areas have been planted with
longer rotation species including dipterocarps (Cedamon
et al. 2011), and there is interest in domesticating indigenous
tree species (Mangaoang and Pasa 2003). Local and national
laws have been enacted to promote planting of native trees,
the most recent being the National Greening Program which
aims to establish 1.5 billion native trees during the next five
years (DENR 2011). There have been several local and
national initiatives to promote planting of native trees, includ-
ing trials of the “Rainforestation Farming System” (known
locally as Rainforestation) established on Leyte Island in the
mid-1990s (Milan et al. 2004). Under this system, fast grow-
ing native species were planted first with successional species
and then with dipterocarps and fruit trees in the subsequent
year.
Mayapis (Shorea palosapis (Blanco) Merr.), a native for-
est hardwood endemic to the Philippines, is a prime candidate
for domestication. It has long been recognised as a prime
timber species (Nablo 1940, Reyes 1959), it is one of the
species most preferred by farmers (Santos et al. 2003), has
one of the highest growth rates amongst dipterocarps in
cultivation (Milan et al. 2004), and is on the IUCN Red List
(Ashton 1998). Despite past exploitation, mayapis remains
one of the most widespread dipterocarps on Leyte, occurring
naturally on a wide range of sites from 100–800 m elevation
(Langenberger 2006). Previous work on reforestation has
recognised its potential, categorising it as a “superb, all pur-
pose” tree (Schulte 1996). However, further work is needed,
as planting stock is problematic and site requirements
remain ill-defined. Mayapis has recalcitrant seeds typical of
494 N.O. Gregorio et al.
FIGURE 1 Trial location in Leyte Leyte, Philippines
distribution of the three field trials within the experiment
area.
Collection of seeds and production of seedlings for the
trials
Suitable mayapis mother trees were identified using the data-
base of premium native trees (Gregorio et al. 2010) and seeds
were collected from four mother trees in the forest reservation
of Visayas State University (VSU) in Leyte Island. Seeds
were sown directly in polybags filled with a potting medium
comprising 60% forest soil, 20% mudpress and 20% rice-
hulls. Fungicide was applied weekly through overhead sprays
until seeds germinated, and subsequent watering, weeding
and pest control applied as needed. Since the potting medium
was relatively fertile, no fertiliser was added to the pots. Seed-
lings were hardened ten weeks after germination by exposure
to full sunlight and reduced watering. Also, seedlings were
placed on elevated beds to promote air-pruning of roots.
The hardening process lasted for one month after which 500
seedlings with relatively uniform height and base diameter
were selected for the trial.
Two of the trials included mahogany, falcata and narra and
these seedlings were propagated together with the mayapis.
Mahogany seeds were collected from five phenotypically
superior mother trees from the VSU forest reservation. Narra
and falcata seeds were purchased from Bukidnon Forest
Industries, a company producing genetically superior seeds
of timber species. Seeds of narra and falcata were sown in
germination boxes with pasteurised medium composed of
60% soil and 40% sand. Young seedlings were potted to indi-
vidual polybags after a pair of leaves formed. Because seeds
of mahogany are relatively large, these were sown directly to
individual pots. The pots were placed on elevated beds and
hardened by exposing to sunlight and reducing water applica-
tion. A total of 250 seedlings with relatively uniform height
and diameter were selected from each species for the field
trials.
Experimental design and treatments
The shading trial employed a randomized complete block
design with two replicates and 15 treatment combinations (5
shade levels and 3 fertilizer rates). Shade treatments included
an untreated control, nurse trees and artificial screens (light,
medium and dense). Screens measuring 60 × 60 cm were
assembled from 4 cm bamboo slats to provide dense, medium
and light dappled shade with densities of 90%, 60% and 30%
FIGURE 2 Google Earth image (4 July 2011), showing vari-
able spacing trial (top), mixture trial (centre, mayapis in
south-west corner), and shading+fertilizer trial (bottom).
Oval indicates watercourse causing seasonal waterlogging
Manila
Developing establishment guidelines for Shorea palosapis 495
respectively. Kakawate (Gliricidia sepium (Jacq.) Steud.) was
used as shade tree as is common practice in agroforestry
plantings locally. Fertilizer treatments included control (no
fertilizer), ‘light’ (65 g) and ‘heavy’ (130 g of 14-14-14
fertiliser per seedling). Fifteen plots were established in each
replicate with each plot comprising 12 seedlings at a uniform
spacing of 3 × 3 m.
Four species were planted in the mixed species trial –
mayapis (native and non-nitrogen fixing); mahogany (exotic
and non-nitrogen fixing); narra (native and nitrogen fixing)
and falcata (exotic and nitrogen fixing). The planting layout
was designed to facilitate investigation of inter- and intra-
specific competition (Vanclay 2006a), with four plots each
planted with 100 seedlings spaced at 3 × 3 m, with the species
mix varying systematically across the plot. The same four
species were planted in the variable spacing trial, which
employed a rectangular layout with spacing varying continu-
ously from 0.6 m at the centre to 7.5 m at the perimeter of
the trial, offering a compact way to evaluate a wide range of
spacings (Vanclay 2006a).
The experiment was established on private land previ-
ously used as livestock pasture, arranged through a Memoran-
dum of Agreement with the owner. The adjacent areas were
irrigated rice fields and smallholder agricultural farms planted
to annual crops. Brushing was undertaken to remove estab-
lished vegetation including pioneer trees, shrubs and tall
grasses. Stems of trees and brushes were removed while
grasses were allowed to decompose on the site. Experiments
were laid out using a compass and tape measure, and planting
locations were marked with stakes. Seedlings were planted
into holes approximately 0.3 m wide and 0.3 m deep. A fence
was constructed around the planting to protect from stray
animals. Quarterly plantation maintenance included removal
of weeds within one meter radius from the base of the
seedlings.
Treatments
Cuttings of the shade tree G. sepium were planted two months
before the planting of mayapis seedlings, by which time the
cuttings were well established and offered considerable shade
to mayapis seedlings. Shade screens were installed immedi-
ately after planting, directly above the seedlings and fastened
to three bamboo poles at the height of approximately 0.3 m
above the shoot tip. Screens were adjusted regularly as seed-
lings grew to maintain 0.3 m clearance between the screen
and the seedling. Because growth rates differed, this adjust-
ment of screens were not synchronous for all seedlings. Both
the shade screens and the shade trees were removed 18 months
after planting.
Fertiliser treatments were applied 45 days after planting,
when seedlings should have formed new roots capable of
absorbing the nutrients applied. Doses were prepared by
weighing and dispensing into sealed, labelled plastic bags
which were emptied and distributed in a trench 5 cm deep,
surrounding and approximately 12 cm from the base of the
seedling. In the mixed species and variable spacing trials, all
seedlings received 130 g of 14-14-14 fertiliser 45 days after
planting.
Tree parameters including total height, base diameter,
diameter at breast height (dbh), and maximum photosynthesis
were measured. Seedling health was also monitored and
recorded. Measurement of dbh commenced 2 years after
planting. Photosynthesis measurements commenced when
seedlings were 6 months old and were repeated regularly
using a LI-COR LI-6400 portable photosynthesis system
(Herbohn et al. 2009b). Height and diameter measurements
were taken at 2-month and 3-month intervals for the first 6–
24 months, after which measurement frequency was reduced
to 6 monthly. Calipers were used to measure basal diameter,
while dbh was measured using a diameter tape. Seedling
height was measured initially with a metre rule, and with a
hypsometer once seedlings exceeded 1 m tall.
RESULTS AND DISCUSSION
Mayapis suffered high mortality in all three trials, averaging
about 40% mortality, partly because of harsh conditions dur-
ing the first year after planting. While this mortality detracts
somewhat from the utility of the trials, the surviving trees
nonetheless convey much useful information about the behav-
iour of this species in plantations. The pattern of mortality in
the spacing trial (Figure 3) is a reminder that mortality is often
spatially clustered (Ashton and Hall 1992) and suggests that
mayapis may perform better at closer spacings.
Survival of mayapis trees was slightly better in the mixed
species trial (Figure 4), but mayapis performed better (both
survival and growth) in the monoculture part of the trial, and
worse in the mixed species composition at the centre of
the trial (correlation r=−0.54). This trial offers insufficient
evidence to assert that mayapis thrives best in a high density
monoculture, but does reveal indicative trends that warrant
further research.
While the spacing (Figure 3) and mixture trials (Figure 4)
suggest some growth characteristics of mayapis, the main
thrust was the shading and fertilizer trial (Figure 5) that sought
to inform establishment practices. Unfortunately, four-year
survival of this planting was poor (52%), with most of the
mayapis in the north-east corner of the trial dying (Figure 6),
apparently due to harsh conditions in the year following plant-
ing and seasonal waterlogging in subsequent years. Initial site
surveys in 2007 suggested a relatively uniform and suitable
site, but it subsequently appeared that the north-east corner
of this trial is liable to seasonal waterlogging, which may
contribute to the high mortality rate experienced in parts of
this trial (Figure 2).
Although the loss of many trees is disappointing, and
detracts from the design (a randomised complete block with
two replications), the trial nonetheless conveys much infor-
mation, and warrants analysis. However, caution is needed in
the analysis, because several factors are confounded. A simple
summary of the data offers a good overview (Table 1): either
fertilizer or shade improves growth, but the effects are not
additive so there is little benefit from both shade and fertilizer.
Nurse trees appear effective, but the benefit derived by the
496 N.O. Gregorio et al.
FIGURE 4 Many of the blanks near the centre of the mixed species trial are due to the death of mayapis trees, which appears to
exhibit better survival and growth is better as a monoculture (top left)
shade tree from the fertilizer may lead to increased competi-
tion for the crop tree (i.e., in Table 1, application of fertilizer
halved the mean size of mayapis under nurse trees from 8 to
4 cm) – such fertilizer-weed interactions have been recorded
elsewhere (e.g., Roth and Newton1996). In Table 1, some
treatments (e.g., 30%, 60% or 90% overhead shade; light
or heavy fertilizer) have been amalgamated to provide
representative samples, but treatment differences remain
non-significant at the usual statistical thresholds (P>0.05).
Treatment differences in Table 1 are not statistically sig-
nificant because of large within-treatment variation, caused in
part by seasonal waterlogging in the north-east corner, poor
health of some mayapis, and site variation. For instance, there
is a strong correlation between tree size (dbh) and distance
FIGURE 3 Spacing trial showing death of Mayapis at wide spacings (bottom right)
Developing establishment guidelines for Shorea palosapis 497
from the waterlogged north-east corner (r=0.57), with visual
assessment of tree health (dead=0, vigorous=5; r=0.55), and
with the basal area of mayapis in the eight nearest planting
positions (r=0.82). There are different ways to deal with such
issues. For instance, distance from north-east corner could be
included in a regression as a covariate, or all planting posi-
tions thought to suffer waterlogging could be excluded from
the analysis. Similarly, tree health could be used as a criterion
to omit some trees from the analysis (e.g., health 1 or 2 are
likely to die, so omit), could be included explicitly as a covari-
ate, or could be included implicitly through the assumption
that health is an outcome of treatment. Fortunately, in this
case, the implications for mayapis planting remain the same
for all these alternatives. However, the correlation with basal
area is different and need not imply that mayapis prefers
crowded stands: instead it reflects the fact that trees are likely
to be big if their neighbours are big because tree size within
each 12-tree treatment subplot should be similar, and because
any site variation means that trees close together should be
more similar than trees far apart.
The analysis that makes best use of all available data is
to include distance from waterlogging (i.e., from north-east
corner) and health as co-variates, and to fit a linear regression
model. This model was fitted to individual tree measurements,
using ARC (Cook and Weisberg 1999). The resulting model
that includes all treatments is:
Sqrt(DBH) = β
0
+ β
1
Distance + β
2
Health + β
3
/Fert.Shade
+ β
4
Nurse + β
5
Nurse/Fert (1)
where Distance is the number of planting positions from the
north-east corner, Health is a visual assessment of tree vigour
(0=dead, 5=vigorous), Fert is fertilizer treatment (1=none,
2=light, 3=heavy), Shade reflects the density of the cage
(0=none, 1=30%, 2=60%, 3=90%) and Nurse indicates the
presence of a shade tree (0=no, 1=yes). The square-root trans-
formation of dbh is desirable to satisfy conventional statistical
assumptions (normally-distributed residuals). All parameter
are significant (Table 2) and trend in ways consistent with
established silvicultural understanding.
FIGURE 5 Shading trial, photographed in November 2008 (left), and October 2009 (right)
FIGURE 6 Shading and fertilizer trial, showing poor
survival of mayapis in north-east corner (at top right of
diagram)
TABLE 1 Mean diameter (cm dbh) versus aggregated treat-
ment at age 4 years (April 2012; all 206 surviving trees)
Fertilizer
Shade
Mean
None Overhead Nurse tree
Unfertilized 4.5 6.5 8.2 6.3
Fertilized 6.8 6.9 4.0 6.4
Mean 6.0 6.8 5.6 6.4
498 N.O. Gregorio et al.
Table 3 offers a more accessible insight than the parame-
ters listed in Table 2, and presents the diameters expected for
a healthy mayapis in the centre of the trial (at median distance
from the waterlogged corner). Equation 1 is consistent with
the results shown in Table 1, implying that either shading or
fertilizer improves growth, but that there is little benefit in
both fertilizer and shade. Nurse trees offer an efficient way to
provide shade and stimulate growth, but fertilizer may stimu-
late the nurse tree to the detriment of the crop tree (e.g., in the
rightmost column of Table 3, more fertilizer means smaller
trees).
Several variants of this analysis were investigated, includ-
ing the omission of treatment subplots affected by waterlog-
ging, the removal of health and/or distance as a covariate, and
the use of treatment means rather than individual trees, but all
lead to conclusions similar to Table 3, but with different error
estimates (and thus different implications for statistical
significance). We also considered the use of spatially-explicit
competition indices (Vanclay 2006b) as explanatory vari-
ables, but they conveyed no significant improvement over
Equation (1). Since the present analysis is concerned less
with testing for significance and more for calibrating well-
established trends, Equation (1) seems appropriate.
Equation 1 is not quite the full story. The 2009 photograph
(Figure 5) is oriented towards the southeast, and it is evident
that mayapis to the left of the foreground person are taller
than those to the right, despite receiving the same treatment,
perhaps because they receive morning shade. An analysis of
inter-treatment shading by shade trees reveals a small but
non-significant effect (Figure 7).
Mayapis (in unshaded treatments) with shade trees to their
west or north are smaller than average, so it seems that they
suffer competition without deriving benefit. But mayapis with
shade trees to the east are slightly larger than the average, so
apparently derive benefit from morning shade. Although this
trend is not statistically significant (in Figure 7 or in Equation
1), it is logical and indicates that mayapis may derive benefit
from alternative planting schemes, such as alternate rows
(especially with rows oriented north-south). Such a scheme
with alternate rows may help overcome resistance to practical
uptake of mixed species plantings (Nichols et al. 2006).
In an attempt to better understand the response of mayapis
to the various treatments, we investigated the light curves of
three of the treatments, the control, shade tree and fertilizer
(Figure 8), because they are strong contrasts. Each of these
treatments have 10–12 trees that reached breast height
and have 3 or more measurements at dbh by 4 years of age.
Figure 8 illustrates the growth pattern of the median tree, and
the corresponding light response curve. It is evident that the
greatest instantaneous photosynthesis is exhibited by fertil-
ized trees, but that overall the best performance is achieved by
mayapis with shade trees. Our interpretation makes an anal-
ogy to the race between the hare and the tortoise: even though
fertilised trees exhibit higher instantaneous photosynthesis,
they cannot sustain this performance throughout the heat of
the day, and overall achieve lower growth than shade trees
that sustain lower photosynthesis throughout a greater pro-
portion of the day. Observations suggest that photosynthesis
in mayapis leaves shuts down at around 34°C, an air tempera-
ture commonly reached in the exposed areas of the site. Shade
cover invariably leads to cooler air temperatures and thus
photosynthesis in shade treatments would have continued
for a longer period during hotter periods. The shape of the
light response curves whereby there is a rapid increase in
TABLE 2 Parameter estimates for Equation 1
Variable Estimate Std. Error Student’s t p-value
Constant −0.634 0.232 −2.73 0.007
Distance 0.038 0.004 8.97 <.001
Health 0.457 0.047 9.66 <.001
1/Fert.Shade −0.294 0.121 −2.44 0.016
Nurse −0.582 0.188 −3.09 0.002
Nurse/Fert 0.955 0.281 3.40 0.001
TABLE 3 Expected mayapis dbh (cm) implied by equation
(1)
Fertilizer
Shading
Nurse
tree
None 30% 60% 90%
None 6.3 7.0 7.3 7.4 8.3
Light 7.0 7.4 7.6 7.6 6.5
Heavy 7.3 7.6 7.6 7.7 5.9
FIGURE 7 Relative size of mayapis receiving shade from
adjacent shade trees. Black line shows relative size of maya-
pis trees; grey shading indicates 95% confidence interval;
dotted line is the reference (average) tree diameter. Shade
from the north is detrimental: both the black trend line
and grey confidence interval remain less than the overall
average
Developing establishment guidelines for Shorea palosapis 499
photosynthesis from 0 to 400 µmol m-2 s-1PAR means that
reasonably high levels of photosynthesis still occur even in
partial shade.
Mycorrhizae have been shown to confer tolerance to
drought and high soil temperature (Lee 1996) and thus to
improve early growth (Turjaman et al. 2005). Bruzon (2002)
recorded that mulching increased height growth of seedlings
by 70%, perhaps by moderating soil temperatures.
Understanding the biophysical factors that affect the
establishment and early success of mayapis is only one step
in the development of successful silviculture for a new planta-
tion species. A further critical requirement is ready availabil-
ity of seedlings. Currently mayapis seedlings are seldom
available in tree nurseries, as is the case with most native spe-
cies in the Philippines (Mangaoang and Pasa 2003, Gregorio
et al. 2008). This is partly due to a lack of germplasm (i.e.,
mayapis only fruits irregularly and there are few natural
forest areas from which wildings can be collected). While
germplasm remains difficult to obtain, government nurseries
are probably best placed to supply planting material because
of their greater ability to access germplasm and propagate less
commonly produced species compared to smallholder and
community nurseries (Gregorio et al. 2008), especially given
that farmers have little knowledge of tree nursery systems
(Baynes et al. 2011a).
Given the shift away from industrial forestry systems in
the Philippines, the domestication of mayapis will involve
planting as part of smallholder and community forestry sys-
tems. The silviculture for mayapis will however differ from
that of commonly grown exotic species such as gmelina and
mahogany. As such, for mayapis to be successfully adopted in
these systems, culturally appropriate extension programs will
need to be developed (Baynes et al. 2011a; Baynes et al.
2011b).
CONCLUSIONS
Mayapis benefits from shade trees, either directly above or
to the east, that provide midday or morning shade. Mayapis
exhibits poor growth and survival under wide spacing, when
waterlogged and in bare soil exposed to full sunlight. Light
response curves suggest that fertilizer helps to increase the
peak photosysnthesis, whilst shade trees modify the microen-
vironment and allow mayapis to photosynthesise actively for
longer each day.
Trial plantings exhibited an average survival of only about
50%, not sufficient for operational plantings by smallholders.
Further research is needed to explore the interaction of soil
temperature and mycorrhiza on seedling survival and growth.
Further study is also needed to explore the feasibility of
operational mixed-species plantings with mayapis, possibly
as alternate rows of mayapis and shade trees.
ACKNOWLEDGEMENTS
This research has been conducted as part of ACIAR project
ASEM/2006/091 Enhancing Tree Seedling Supply via
Economic and Policy Changes in the Philippines Nursery
Sector.
REFERENCES
ASHTON, P. 1998. Shorea palosapis. In IUCN 2012. IUCN
Red List of Threatened Species, Version 2012.1, www.
iucnredlist.org [15 August 2012].
ASHTON, P.S. and HALL, P. 1992. Comparisons of structure
among mixed dipterocarp forests of north-western Borneo.
Journal of Ecology 80(3): 459–481.
FIGURE 8 Growth curves (left) and light response curves (right) of the median tree in three treatments (1=no shade, no fertil-
izer; 5=shade tree, no fertilizer; 11=no shade, with fertilizer)
500 N.O. Gregorio et al.
BAYNES, J., HERBOHN, J.L. and RUSSELL, I. 2011a. The
influence of farmers’ mental models on an agroforestry
extension program in the Philippines. Small-scale Forestry
10: 377–387.
BAYNES, J., HERBOHN, J.L., RUSSELL, I. and SMITH, C.
2011. Bringing agroforestry technology to farmers in the
Philippines: Identifying constraints to the success of
extension activities using systems modelling. Small-scale
Forestry 10: 357–376.
BEVEGE, D.I. and RICHARDS, B.N. 1970. Nitrogen in the
growth of Araucaria cunninghamii Ait. underplanted in
Pinus stands. Ecology 51(1): 134–142.
BRUZON, J.B. 1978. Fertilization of potted mayapis Shorea
palosapis seedlings in Surigao del Sur. Sylvatrop 3(3):
201–204.
BRUZON, J. 2002. Field testing of rooted dipterocarp
cuttings. PCARRD Highlights 2002:119–120.
BULLECER, R.C. 2011. Domestication performance of
indigenous trees: a decade of rainforestation experience in
degraded karst lands. IAMURE: International Association
of Multidisciplinary Research Journal 2: 237–255.
CEDAMON, E., HARRISON, S. and HERBOHN, J. 2011.
Compiling market and other financial data on smallholder
forestry in Leyte, the Philippines. Small-scale Forestry
10: 149–162.
COOK, R.D. and WEISBERG, S. 2009. Applied regression
including computing and graphics. Wiley-Interscience.
DAMATTA, F.M., RONCHI, C.P., MAESTRI, M. and
BARROS, R.S. 2007. Ecophysiology of coffee growth
and production. Brazilian Journal of Plant Physiology
19(4): 485–510.
DEPARTMENT OF ENVIRONMENT AND NATURAL
RESOURCES (DENR). 2011. Executive Order No. 26,
National Greening Program, accessed 10 August 2012
http://ngp.denr.gov.ph/.
DY, R.T. and BAUTISTA, M.D. 1999. The wood industry in
the Philippines: supply and demand situations and
projections, Paper presented during the Second Tree
Farming Congress in Tagum City, Davao del Norte, 13–14
April, 1999.
FORRESTER, D.I., BAUHUS, J., COWIE, A.L. and
VANCLAY, J.K. 2006. Mixed-Species Plantations of
Eucalyptus with nitrogen fixing trees: A review. Forest
Ecology and Management 233: 211–230.
GREGORIO, N.O., HARRISON, S.R. and HERBOHN, J.L.
2008. Enhancing seedling supply to smallholders in Leyte
Province, Philippines: An evaluation of the production
system of government nursery sector and support to
smallholder tree farmers. Small-scale Forestry 7: 245–
261.
GREGORIO, N.O., VANCLAY, J. and HERBOHN, J.L.
2009. Establishing field trials to promote smallholder
forestry in Leyte, The Philippines. In S.R. Harrison, A.
Bosch, J. Herbohn and E. Mangaoang (eds) Proceedings
from the End-of-Project Workshop held in Ormoc City,
the Philippines. ACIAR Smallholder Forestry Project:
Improving Financial Returns to Smallholder Tree Farmers
in the Philippines, End-of-Project Workshop, Sabin Resort
Hotel, Ormoc City, Leyte, (75-82). 11–12 February
2009.
GREGORIO, N., DOYDORA, U., HARRISON, S.R.,
HERBOHN, J.L. and SEBUA, J. 2010. Inventory and
assessment of mother trees of indigenous timber species
on Leyte Island and Southern Mindanao, the Philippines.
In: S.R. Harrison, A. Bosch, N.O. Gregorio and J.L.
Herbohn (eds) Proceedings of End-of-Project Workshop:
ASEM/2006/091 Enhancing Tree seedling Supply via
Economic and Policy Changes in the Philippines Nursery
Sector. Leyte, Philippines, 19–20 June 2010. Pp. 113–125.
http://espace.library.uq.edu.au/eserv/UQ:242935/NG13.
pdf
GUIANG, E.S. 2001. Impacts and effectiveness of logging
bans in natural forests: Philippines. In P.B. Durst et al.
(eds) Forests Out of Bounds: Impacts and Effectiveness
of Logging Bans in Natural Forests in the Asia Pacific,
Bangkok, UNFAO Regional Office for Asia and the
Pacific.
HERBOHN, J.L. and HARRISON, S.R. 2005. Improving
Financial Returns to Smallholder Tree Farmers in the
Philippines: Issues and Way Forward. In: J. Suh, S.R.
Harrison, J.L. Herbohn, E.O. Mangaoang and J. Vanclay,
ACIAR Smallholder Forestry Project ASEM/2003/052
Improving Financial Returns to Smallholder Tree Farmers
in the Philippines Proceedings from the ACIAR Project
Planning Workshop held in Ormoc City the Philippines
15–17 February 2005. ACIAR Smallholder Forestry
Project – Improving Financial Returns to Smallholder
Tree Farmers in the Philippines, Ormoc City, the
Philippines, pp. 7–20.
HARRISON, S., EMTAGE, N.F. and NASAYAO, E.E. 2004.
Past and present forestry support programs in the
Philippines, and lessons for the future. Small-Scale
Forestry 3: 303–317.
HERBOHN, J., HARRISON, S., MANGAOANG, E.,
GREGORIO, N., CEDAMON, E., RUSSELL, I. and
VANCLAY, J. 2007. Improving the Triple Bottom Line
Returns from Smallholder Tree Farms in the Philippines:
A Systems Approach. In: S. Harrison, A. Bosch and J.
Herbohn (eds) Improving the Triple Bottom Line Returns
from Small-scale Forestry, Ormoc, Philippines, pp. 205–
214.
HERBOHN, J., GREGORIO, N. and VANCLAY, J. 2009a.
Rationale and key research questions addressed by field
trails established as part of the ACIAR Smallholder Tree
Farmer Project. In: S. Harrison, A. Bosch, J. Herbohn
and E. Mangaoang (eds) ASEM/2003/052 Improving
Financial Returns to Smallholder Tree Farmers in the
Philippines End-of-Project Workshop held in Ormoc City,
the Philippines, 11–12 February 2009. pp. 67–74.
HERBOHN, J.L., GREGORIO, N.O. and VANCLAY, J.
2009b. Initial gas exchange results from field trials. In:
S.R. Harrison, A. Bosch, J. Herbohn and E. Mangaoang
(eds) Proceedings from the End-of-Project Workshop
Held in Ormoc City, the Philippines. ACIAR Smallholder
Forestry Project: Improving Financial Returns to
Developing establishment guidelines for Shorea palosapis 501
Smallholder Tree Farmers in the Philippines, End-of-
Project Workshop, Sabin Resort Hotel, Ormoc City, Leyte,
(83-91). 11–12 February 2009.
LANGENBERGER, G. 2006. Habitat distribution of
dipterocarp species in the Leyte Cordillera: an indicator
for species – site suitability in local reforestation programs.
Annals of Forest Science 63: 149–156.
LEE, S.S. 1996. Root symbiosis and nutrition. In S. Appanah
and K.C. Khoo (eds) Dipterocarps: State of knowledge
and priorities and needs for future research. Proceedings,
Fifth Round-Table Conference on Dipterocarps, Chiang
Mai, Thailand, 7–10 November 1994. FRIM, Kepong.
542 p.
MANGAOANG, E.O. 2002. A forester’s perspective of the
socio-economic information requirements for forestry in
Leyte. In: S. Harrison, J. Herbohn, E. Mangaoang and
J. Vanclay (eds), Socio-economic Research Methods in
Forestry: A Training Manual, Cooperative Research
Centre for Tropical Rainforest Ecology and Management,
Rainforest CRC, Cairns, pp. 1–14.
MANGAOANG, E.O. and PASA, A.E. 2003. Preferred native
tree species for smallholder forestry in Leyte. Annals of
Tropical Research 25(1): 25–30.
MARGRAF, J. and MILAN, P.P. 1996. Ecology of dipterocarp
forests and its relevance for island rehabilitation in Leyte,
Philippines. A. Schulte, A. and D. Schöne (eds) Dipterocarp
Forest Ecosystems: Towards sustainable management.
World Scientific, Singapore. Pp. 124–154. http://books.
google.com.au/books?id=oHNzvs02F5wC&pg=PA124&
ots=p85m5ub3Ks.
MAROHN, C. 2008. Rainforestation farming on Leyte island,
Philippines – aspects of soil fertility and carbon
sequestration potential. Thesis, Universität Hohenheim.
http://opus.ub.uni-hohenheim.de/volltexte/2008/218/.
MILAN, P.P., CENIZA, J.C., ASIO, V.B., BULAYOG, S.B.
and NAPIZA, M.D. 2004. Evaluation of silvicultural
management, ecological changes and market study of pro-
duction of existing rainforestation demo and co-operators
farms. Terminal Report, GTZ. www.rainforestation.ph/
resources/pdf/publications/Milan_et.al._nd_Terminal_
Report_Evaluation_of_Silvicultural_Management.pdf.
NABLO, S.U. 1940. A commercial volume table for Mayapis.
Philippine Journal of Forestry 3: 451–469.
NICHOLS, J.D., BRISTOW, M. and VANCLAY, J.K. 2006.
Mixed Species Plantations: Prospects and Challenges.
Forest Ecology and Management 233: 383–390.
NICHOLS, J.D. and VANCLAY, J.K. 2012. Domestication of
native tree species for timber plantations: Key insights for
tropical island nations. International Forestry Review
14(4): 402–413.
OTSAMO, R. 1998. Effect of nurse tree species on early
growth of Anisoptera marginata Korth. (Dipterocarpaceae)
on an Imperata cylindrica (L.) Beauv. grassland site in
South Kalimantan, Indonesia. Forest Ecology and
Management 105: 303–311.
PALER, R.R. and ALCOBER, Q.C. 1991. Preliminary results
on rooting of cuttings of almon, red lauan, mayapis,
tanguile, apitong and white lauan. Philippine Lumberman
37(6): 34–37.
REYES, M.R. 1959. Natural regeneration of the Philippine
dipterocarp forest. Philippine Journal of Forestry 15:
39–61.
ROTH, B.E. and NEWTON, M. 1996. Survival and growth of
Douglas-fir relating to weeding, fertilization, and seed
source. Western Journal of Applied Forestry 11(2): 62–
69.
SANTOS, F., BERTOMEU, M., VEGA, B., MANGAOANG,
E., STARK, M. and BULLECER, R. 2003. Local
knowledge on indigenous trees: towards expanding
options for smallholder timber tree planting and improved
farm forestry in the Philippine uplands. H.C. Sim, S.
Appanah and P.B. Durst (eds) Bringing Back the Forests:
Policies and Practices for Degraded Lands and Forests.
RAP Publication 2003/14, pp. 75–84.
SCHULTE, A. 1996. Dipterocarp Forest Ecosystems: Towards
sustainable management. World Scientific, Singapore.
pp. 146.
TURNER, I.M., BROWN, N.D. and NEWTON, A.C. 1993.
The effect of fertilizer application on dipterocarp seedling
growth and mycorrhizal infection. Forest Ecology and
Management 57: 329–337.
TURJAMAN, M., TAMAI, Y., SEGAH, H., LIMIN, S.H.,
CHA, J.Y., OSAKI, M. and TAWARAYA, K. (2005).
Inoculation with the ectomycorrhizal fungi Pisolithus
arhizus and Scleroderma sp. improves early growth of
Shorea pinanga nursery seedlings. New Forests 30(1):
67–73.
VANCLAY, J.K. 2006a. Experiment designs to evaluate inter-
and intra-specific interactions in mixed plantings of forest
trees. Forest Ecology and Management 233: 366–374.
VANCLAY, J.K. 2006b. Spatially-explicit competition indices
and the analysis of mixed-species plantings with the
Simile modelling environment. Forest Ecology and
Management 233: 295–302.
VANCLAY, J.K., SKOVSGAARD, J.P. and HANSEN, C.P.
1995. Assessing the quality of permanent sample plot
databases for growth modelling in forest plantations.
Forest Ecology and Management 71: 177–186.
Visayas State University, c.1995. Guide to Rainforestation
Timber Species. Visayas State University, Institute of
Tropical Ecology, 12 p.
WEINLAND, G. 1998. Plantations. In S. Appanah and J.M.
Turnbull (eds) A Review of Dipterocarps: Taxonomy,
ecology and silviculture. CIFOR, Bogor. pp. 151–186.
ZABALA, N.Q. 1993. Mass Vegetative Propagation of
Dipterocarp Species. UNDP/FAO Regional Project on
improved productivity of man-made forests through
application of technological advances in tree breeding and
propagation (RAS/91/004). 16 p.
