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Transcript
SURVEY on main Forest Types and Tree Species
in Xishuangbanna and its Photo-Documentation
Consultancy Report
Dr. Ulrich Apel
GFA — terra systems
Eulenkrugstr. 82
22345 Hamburg
Germany
Jinghong, Xishuangbanna
February 2001
Table of Contents
1.
Background and Objective of the Assignment
2.
Findings
*
*
2.1
Physical geography of Xishuangbanna
2.2
Factors influencing forest structure and species composition in Xishuangbanna
*
2.3
Forest formations and local vegetation types in Xishuangbanna
2.4
Main plant families and species in Xishuangbanna *
3.
Conclusion and Recommendations
*
List of Annexes
Annex 1: Terms of Reference
Annex 2: Description of Species
Annex 3: Photo-Documentation (separately)
Abbreviations
a.s.l.
above sea level
DBH
diameter at breast height (1.3 m)
MEBF
montane evergreen broad-leaved forest
TEF
tropical evergreen rainforest
TS-EF
tropical semi-evergreen (monsoon) forest
*
*
1.
Background and Objective of the Assignment
Since 1998, the Tropical Forest Ecosystems Management Project (TEFM) has collected
extensive material about biodiversity in Xishuangbanna and documented with photographs for
the purpose of biodiversity monitoring and documentation of the biodiversity in the project pilot
sites. The documentation focussed on birds, butterflies, reptiles, orchids, ferns, and non-timber
forest products used by the ethnic minorities. However, forest types and its main tree species
have not been sufficiently covered so far.
The objective of this short-term assignment was to conduct a survey on the main forest types in
Xishuangbanna and to describe their main representative plant families and tree species as well
as other characteristic plants such as palms, climbers, and bamboo. The species were to be
described in text and with photographs to serve future needs for publication in print or websites.
As Xishuangbanna is a biosphere reserve, the links between the ethnic groups living in this area
and the biodiversity were to be regarded and traditional uses made of the native plants
investigated (see also ANNEX 1: Terms of Reference).
This short-term consultancy has been carried out from 4 — 28 February, 2001. The consultant
based the survey on the available literature about Xishuangbanna´s and adjacent forest
ecosystems,,,, as well as on own investigations.
2.
Findings
1. Physical geography of Xishuangbanna
Topography
Xishuangbanna is located in the southernmost tip of Yunnan province bordering
Myanmar in the Southwest and Laos in the Southeast. It covers an area of about
20,000 km_. Altitudes range between 410 — 2,400 m a.s.l. The terrain is hilly to
montane with average altitudes between 800 and 1000 m. Almost all streams are
tributaries of the Mekong which bisects Xishuangbanna from North to South.
Climate
The climate is strongly seasonal with two main air masses alternating during the
year: between May and October the South-West Monsoon delivers about 80% of
the annual rainfall, whereas the dry and cold air of the Southern edges of the jet
streams dominate the climate between November and April. Annual rainfall
varies between 1200 mm in the Mekong valley and 1900 mm in altitude above
1500 m. Although the rainfall is very seasonal the dry season is not extreme in
nature. Fog with an average duration of 6 hours occurs on about 130 days, mainly
in the dry season.
2. Factors influencing forest structure and species composition
in Xishuangbanna
The seasonal climate coupled with the complex topography has resulted in a
natural vegetation pattern consisting of both evergreen and deciduous forest
patches and resulting in high species diversity. A long history of human
interaction has further influenced the forests that prevail today. The structure and
species composition in a particular forest patch depends on three main factors:
moisture, altitude, and human interaction.
Moisture
The moisture of a particular site is strongly related to rainfall, topography, and
geology. Although lowland areas have less rainfall, plants can often access
ground water. In Xishuangbanna, fog in valley and lowland areas provides
moisture in the dry season. Valleys and concave slopes provide more moist
conditions than ridges and convex slopes. Exposition to North usually provides
moist and shady conditions for a longer period of time. The best soils for retaining
moisture available to plants have a high content of organic matter and a balanced
proportion of sand, silt and clay.
Plants that are not confined to water supply throughout the year have developed
approaches to avoid excessive water loss. Typical for monsoon forest in
Xishuangbanna is the deciduous habit of the emergent trees that shed their leaves
in the dry season. In higher elevation with sandy soils, a sclerophyllus habit is
common. The dominant tree species have developed thick leaves with waxy
coating to reduce water loss.
Altitude
Highland areas have lower temperatures than lowland areas. The occurrence of
frost causes sharp transitions in the vegetation. In Xishuangbanna frost days are
likely above 1200 m. More rainfall in higher elevations does not necessarily
provide more moisture to plants. Sandy and poor soils in higher elevation cause
less available water for plants. Topography continues to play a significant role
with exposed ridges and shady valleys supporting different vegetation than
intermediate areas.
Human interaction
Human interaction plays a very important role in Xishuangbanna, which has been
inhabited by different ethnic groups probably since more than 4000 years. Each
ethnic group has developed its characteristic forms of land use shaping the
environment they live in. The interactions with the forest include shifting
cultivation, timber and fuelwood harvesting, cultivation in the forest, collection of
various non-timber forest products, and religious motivated protection of
designated forest patches and certain species as well as the introduction of exotic
plants.
The main ethnic group, the Dai are well known for preserving holy hills and large
strangler figs out of religious motivation. The Dai have introduced many species
related to Buddhism that are now common in Xishuangbanna, such as
Dipterocarpus turbinatus, Ficus religiosa, and Mesua ferrea. The fast-growing
Cassia siamea has been introduced for fuelwood production in a coppice system
and taken up by other ethnic groups. Cultivation of Amomum villosum under the
forest canopy has changed the forest structure in many village forests in
Xishuangbanna. The selective cutting of timber with good wood properties for
house building has led to changes in species composition in most village forest
areas. Species like Ficus spp., Gmelina arborea, and Schima wallichii are more
common after disturbances in the natural forest.
Hill tribes such as Hani, Yao, Lahu, Yi and Jinuo practise shifting cultivation,
whereas Kemu and Kucong are predominantly hunters and gatherers. The Jinuo
cultivate tee under the forest cover leading to characteristic coppice forests with
by huge emergents. Shifting cultivation systems practised by these ethnic groups
have led to high proportions of pioneer species such as Macaranga spp.,
Duabanga grandifolia, Anthocephalus chinensis, as well as Bamboo species.
Furthermore, useful species with edible fruits etc. are often retained in shifting
cultivation systems influencing species composition when the forest regenerates.
3. Forest formations and local vegetation types in Xishuangbanna
The survey identified three main forest formations and five local vegetation types in
Xishuangbanna.
I
Tropical evergreen rainforest (TEF)
Tropical evergreen rainforest occurs in Xishuangbanna in moist areas and in altitudes up to 800
m. In mature forest stands the largest trees reach up to 50 m in height, or more in the case of
Parashorea chinensis. The middle storey is at 20-25 m; a well developed under storey can be
found. Epiphytic ferns, orchids, and semi-epiphytes such as Schefflera spp. and Ficus spp. are
abundant on the trees. These forests are dominated by members of the plant families
Myristicaceae, Guttiferae, Lecythydaceae, Rubiaceae, and Meliaceae. Dipterocarpaceae
(Parashorea chinensis, Vatica xishuangbannaensis) are only occurring in the south-eastern part
of Xishuangbanna below 700 m. Besides the above mentioned Parashorea chinensis common
species include Pometia tomentosa, Barringtonia macrostachya, Terminalia myriocarpa,
Chisocheton siamensis, Tetrameles nudiflora, Metadina trichotoma, Horsfieldia glabra,
Myristica yunnanensis, Knema spp., Garcinia spp., Mitrephora spp., Pittosporopsis kerrii, and
Baccaurea ramiflora. Locally abundant palm species include Caryota ochlandra, Calamus spp.,
and Pinanga spp.
The occurrence of these tree families and species points to floristic similarities with rainforests in
Southeast Asia. However, as Xishuangbanna is located at the northern margin of tropical SE
Asia and is a transitional area between the tropics and subtropics, many typical tropical plants
reach their distributional limits and some of the truly tropical plant families and genera that are
rich in species in tropical SE Asia have only a few representatives here. Still, the TEF are the
richest in terms of species diversity in Xishuangbanna. Species densities of 140 tree species (>
10 cm diameter DBH) per hectare are not uncommon in the Nature Reserves, because the forest
flora is endowed with tree families and species of the subtropical flora of Southern China.
II
Tropical semi-evergreen (monsoon) forest (TS-EF)
Monsoon forest prevails in altitudes between 800 m and 1000 m. Locally, where the climate
shows a more distinctive seasonality it can be found below 800 m. The structure of these forests
is characterised by a less closed canopy formed by emergents with big crowns which shed their
leaves during the dry season, whereas the under story and middle story layer remains evergreen.
In this transitional zone between evergreen tropical rainforest and subtropical evergreen broadleaved forest, a mix of evergreen and deciduous tree species can be found. Species densities
reach up to of 80 — 100 tree species (> 10 cm DBH) per hectare. Typical tree families are
Moraceae, Sapindaceae, Anacardiaceae, Tiliaceae, and Leguminosae. Common species include
Ficus altissima, Toona sinensis, Nephelium chryseum, Altingia excelsa, Bischofia javanica, and
Colona floribunda. On dryer sites Bombax ceiba, Erythrina stricta, and Bauhinia variegata are
common.
III
Montane evergreen broad-leaved forest (MEBF)
This montane evergreen formation is the characteristic and predominant vegetation type in
Xishuangbanna covering altitudes between 1000 m and 2400 m, accounting for 80% of the forest
area. The structure of these forests is simpler than in the lowland and monsoon forests, with very
few emergents and poorly developed under story/shrub layers. The trees forming the canopy are
almost entirely evergreen and reach a dense cover of 90% with a mean height of 20-25 m.
Dominant tree families are Fagaceae and Lauraceae, mixed with Theaceae, Magnoliaceae,
Myrtaceae, Juglandaceae, and Elaeocarpaceae. Common species include Castanopsis hystrix, C.
mekongensis, Lithocarpus truncatus, Litsea glutinosa, Actinodaphne henryi, Schima wallichii,
Syzygium yunnanensis, Elaeocarpus austro-yunnanensis, Paramichelia baillonii, Engelhardtia
spp. Smaller trees in the under story include Machilus salicina, Olea rosea, Aporusa spp. Species
densities range between 50 — 80 tree species (> 10 cm DBH) per hectare.
IV
Local vegetation types
(1) Limestone forest
Limestone outcrops in Xishuangbanna mainly occur in an area around Menglun ranging from
small pockets to larger massifs. Although very few species are restricted to limestone, these
outcrops support interesting forest types and contain many species that have been eliminated in
areas that are more accessible. Since limestone causes dryer conditions, Monsoon forest types
are common also in lower elevations. Typical species are Ficus spp., Tetrameles nudiflora,
Bauhinia variegata, and Mitrephora thorelii.
(2) Pine forest
Natural pine forests are found on an area of about 500 ha at altitudes between 1200 — 1800 m.
Species diversities range from 10 — 15 tree species per hectare. The dominating species is Pinus
khasya var. langbianensis which usually makes up 80% of the individual trees. The remaining
20% are a mixture of Lithocarpus sp., Quercus dentata, Schima wallichii, Betula alnoides, and
Engelhardtia spicata.
(3) Bamboo forest
Bamboo forests occur at altitudes below 1000 m. They cover a quite large area, however, it is
difficult to distinguish between naturally occurring bamboo forests and bamboo forest that are
the result of various forms of degradation. Naturally, bamboo forests would probably cover less
area. Main species include Dendrocalamus strictus, D. brandisii, Cephalostachyum pergracile,
Indosasa sinica, Schizostachyum funghomii, and Dinochloa puberula a climbing species.
(4) River gallery forest
River gallery forests occur along small rivers below 700 m altitude, mainly along the Nanlahe,
Nanmanhe, Nanmuyanghe, Mengyanghe, and the Luosojiang. The species composition is mainly
influenced by the velocity of the running water and duration of flooding of the riverbanks.
Characteristic tree species are Pterocarya tonkinensis, Ficus auriculata, F. heterophylla, F.
gasparriniana var. esquirolii, Salix spp., Dillenia indica, Syzygium fluviatilis, Itea riparia, and
Flemingia fluminales.
(5) Deciduous forest
Deciduous forests are only found on a small area of about 300 ha in Xishuangbanna between
altitudes of 1400 — 2400 m. The canopy layer reaches about 30 m in height; the species
diversity is low, reaching only about 10 species per hectare. These forests are almost completely
dominated by Alnus nepalensis, which usually makes up more than 90% of the individual trees.
Other tree species include Albizzia sp., Celtis sp., Melia toosenden, Castanopsis mekongensis,
Prunus plurinervis, and Elsholtzia ciliata.
2.4
Main plant families and species in Xishuangbanna
The survey identified 28 plant families as the main elements of Xishuangbanna´s forest types. 26
families include mainly tree species, 2 families (Palmae and Gramineae) include palms and
bamboo. The description of the species is structured along habit, botany (bark, leaves, flower,
fruit), ecology, distribution, and uses. The description focuses on the ecology of the species, its
habitat and association with other plants. Furthermore, uses of the different ethnic minorities
have been included as far as it could be investigated.
The photographs taken cover the habit and botanical characteristics of the plants. Since flowering
and fruiting periods of the different are very divers, only a few species could be fully
documented with all their features. This will have to be continued by the TFEM project in the
future.
For the description of the tree species kindly refer to ANNEX 2. For the photographs kindly refer
to the separate ANNEX 3.
3.
Conclusion and Recommendations
Although Xishuangbanna covers only a relatively small area of about 20,000 km_, the vegetation
pattern is very divers. Three main forest formations and five vegetation types with local
importance can be distinguished. Species diversity in all vegetation types is comparably high and
many endemic plants can be found. However, the three main forest formations show clear
floristic similarities to forests in the wider region. The tropical evergreen rainforest contains
many floristic elements of rainforests in SE-Asia. The monsoon forest shows similarities to
forests in India and Myanmar, and the montane evergreen broad-leaved forest is transitional to
subtropical forests of Southern China.
Being inhabited by 14 ethnic groups, Xishuangbanna´s ecosystems have a varying degree of
human interaction which is characterised by different forms of land and forest use of each ethnic
group. Cultural links between the ethnic groups and the forest ecosystems have influenced the
structure and floristic composition of the prevailing forests. In some cases these interactions have
even enriched the ecosystems, in other cases the species diversity decreased. Xishuangbanna´s
total area is a biosphere reserve. The protection of the forests has, therefore, to involve the ethnic
groups.
In this context it is an important activity of the TFEM project to monitor and document
biodiversity with special regard to the use and management of the forest by different ethnic
groups. The survey conducted by the consultant provides an overview about the main vegetation
types and its typical components. On this basis, the project should further collect useful
information and add to this survey.
Annex 1: Terms of Reference
Terms of Reference
for and international short-term consultant on a survey on the main forest types and
forest tree species in Xishuangbanna and their documentation with photographs
1. Objective:
The main objective of the consultancy is to describe the main forest types
in Xishuangbanna and typical representatives of their characteristic plant families.
2. Timeframe: 0.8 months, to be conducted in February 2001.
3. Required Profile:
The consultant should have a background in tropical ecology or
forestry. He/she must be familiar with predominant tree species in Xishuangbanna.
Experience in Mainland SE Asia is prerequisite, experience in Xishuangbanna an asset.
4. Detailed Tasks:
a) Conduct a survey on the main forest types in Xishuangbanna.
b) Identify the plant families which form the main elements of these forest types.
c) Describe characteristic representatives of these families, including the
description of botany and ecology of the species as well as uses by ethnic
groups.
d) Document botanical features of the species by photographs.
e) Present the results in a brief report.
Annex 2: Description of Families and Species
(Draft version 28/02/2001)
Verbenaceae
Cosmopolitan family with 5 genera and 29 tree species in Xishuangbanna. Common species
include Gmelina arborea, Callicarpa arborea, Vitex quinata.
Gmelina arborea
Habit: Deciduous tree, medium sized (up to 25 m height), fast growing.
Bark pale creamy brown or greyish. Leaves decussate, simple with a tip and slightly heartshaped base. Flower yellow-brown, in narrow branched clusters, flowering February — March.
Fruit 2-3 cm, greenish-yellow, fleshy with a hard 1-2 seeded stone, fruiting April — June.
Ecology: Can be found in TEF and TS-EF, especially in disturbed areas, prefers moist
conditions. Often planted in Dai homegardens. Easy to be propagated through seedlings.
Distribution: Found in Jinghong and Mengla, also common in India, Myanmar, Laos, and
Vietnam.
Uses: valuable house building timber, flowers are used by the Dai to sweeten rice.
Note: Protected in China (class II).
Moraceae
Pantropical family with more than 1000 species. 7 genera and about 80 species in
Xishuangbanna. Common species include Antiaris toxicaria, Artocarpus tonkinensis,
Broussonetia payrifera, Ficus altissima, Ficus auriculata, Ficus variegata.
Ficus altissima
Habit: Mostly evergreen, strangling fig, up to 50 m in height, eventually becoming one of the
largest trees in the forest.
Bark thin and smooth, light grey, cut parts with white latex. Leaves spirally arranged simple; 821 cm x 5-12 cm, elliptic to oblong, hairless; dark green above, below light green; midrib
prominent. Flowers numerous, unisexual or sterile (gall), contained in the figs. Fruit at the end
of the twigs, dimensions 1.7-2.8 cm, yellow-orange when ripe. Due to symbiosis with specific
gall-wasp Ficus can produce figs several times a year.
Ecology: Occurs mainly in disturbed areas of TS-EF and MEBF. Sparsely occurs in TEF. The
Species is light demanding. It begins life as an epiphyt on host trees through seeds dispersed by
animals. Vigorous growth and strangling of the host after the roots have reached the soil. Ficus
altissima is considered a "keystone species" in tropical ecosystems which support frugivore
animal populations ranging from birds to small mammals through their enormous and
asynchronous fructification.
Distribution: Widespread and common in Xishuangbanna; widely distributed in whole mainland
Southeast Asia.
Uses: The tree is regarded as a holy tree by the Dai and many other ethnic groups. Its striking
growth form and the special features of the pollination biology make Ficus altissima predestined
to be a realm of spirits. Large specimen occur naturally in holy hills and sacred forests as well as
planted near temples and pagodas. The wood is not used. Latex can be used to treat wounds.
Ficus auriculata
Habit: Small independent growing evergreen tree, up to 12 m height with big crown and
crooked trunk.
Leaves 15-37 x 11-30 cm, broadly ovate or almost circular with widely spaced blunt teeth. Figs
5-8 cm, densily clustered along short woody stumps hanging from main trunk and branches; redbrown or dark purple when ripening.
Ecology: Common in TEF, especially along streams. Planted in homegardens and around
fishponds.
Distribution: Widespread in Xishuangbanna, also distributed in Northern Thailand and Southern
China.
Uses: Edible fruits; many ethnic groups use young leaves as vegetable. The leaves are called
"elephant ears" by the Dai.
Dipterocarpaceae
Tree family with 680 species almost exclusively in Asia, concentrated in the rainforests of
Malaysia and Indonesia. In Xishuangbanna 2 genera with 1 species each occur: Parashorea
chinesis and Vatica xishuangbannaensis.
Parashorea chinensis
Habit: Large evergreen tree, up to 75 m height with tall straight bole and rather open crown.
Small buttresses from 1 — 4.5 m height.
Bark: pale brown to grey, peeling in thin, rounded flakes. Leaves simple, alternate 6-20 x 3-8
cm, small stipules 0.5-1 cm. Flower yellow-white, flowering May-June. Fruit with 5 (3 long and
2 shorter) wings, fruiting Juli — September.
Ecology: Restricted to TEF at lower altitudes (< 700 m a.s.l.). In stands where the species
occurs, the trees almost entirely dominate the canopy layer. Natural regeneration is abundant;
due to meristematic dormancy seedlings and small trees are shade-bearing for many years, with
rapid growth in when gaps open. Grows together with Pometia tomentosa, Cinnamomum
bejolghota, Chisocheton siamensis, Pittosporopsis kerrii, Garcinia spp., Baccaurea ramiflora,
Pseudouvaria indochinensis. Experience with planting hardly exist. Seedling production is
difficult, germination rates in nurseries low. Collection of wild seedlings and immediate potting
in the forest is more successful.
Distribution: Occurs in Xishuangbanna confined to a small area inside the Mengla Nature
Reserve. Also distributed in Northwestern Vietnam Muong Nhe Nature Reserve and Cuc Phuong
National Park.
Uses: House building timber used by Hani and Dai ethnic groups. The timber is, however, not
much valued by the local ethnic groups.
Note: Protected in China (class I).
Juglandaceae
Tree family with 59 species and an unusual distribution pattern — North temperate, Malesia and
South America. In Xihuangbanna 3 genera with 8 species. Common are Engelhardtia spicata
and Pterocarya tonkinensis.
Pterocarya tonkinensis
Habit: Briefly deciduous tree, medium — big size, up to 25 m height.
Bark white — greyish, cracked, inner bark fibrous. Leaves compound 10-18 cm, leaflets with
teeth, 8-12 pairs. Flower minute, in slender branched catkins hanging from the twigs; flowering
March-April. Fruit 2-winged, seeds 0.7 cm, fruiting Juli — August.
Ecology: This species grows along rivers in gallery forests together with Ficus auriculata, F.
heterophylla, and Salix spp.
Distribution: Very common along small rivers in Xishuangbanna; further distributed in
Southwestern and Southern China, Laos, Vietnam.
Uses: The leaves are used for fish poisoning. Fibres can be used. The tree is also used for ritual
fires by the Dai. The wood is very light and soft, it is hardly used for timber or fuelwood.
Fagaceae
Predominantly temperate family with 700 species worldwide. 5 genera and 49 species in
Xishuangbanna. Common species include Castanopsis hystrix, C. mekongensis, C. fleuryi,
Lithocarpus truncatus, L. grandifolius, Quercus acutissima. Fagaceae form the dominant
component of the montane evergreen broad-leaved forest.
Castanopsis hystrix
Habit: Evergreen tree up to 30 m height. Lower trunk up to 1 m in diameter.
Bark grey brown to dark brown, fairly smooth with round flakes at the lower part of the trunk.
Leaves 5-12 x 2-3 cm, dark green above, red-brown below; not toothed. Fruit single, 1.5 cm in
upright spikes, 6 —13 mm long. Flowering April — June, fruits in September — November.
Ecology: Very common tree species in MEBF in altitudes from 1000 — 2000 m. In dryer
conditions often the dominant tree species mixed with Castanopsis fleuryi, Lithocarpus
microspermus, Actinodaphne henryi, Phoebe minutiflora, Syzygium spp. Strong coppicing ability
and good natural regeneration, shade-tolerant when young. The species becomes increasingly
abundant after disturbances (e.g. fire).
Distribution: Common in whole Xishuangbanna, widely distributed in Mainland Southeast
Asia.
Uses: Mainly for firewood, the Dai use good bole forms for house building timber. Fruits are
edible.
Castanopsis mekongensis
Habit: Evergreen tree up to 25 m height. Lower trunk up to 80 cm in diameter.
Bark grey and fairly smooth, twigs hairy. Leaves 10-25 x 3-7 cm, with yellow to golden hairs
below, not toothed. Fruit single, 1.5 — 2.0 cm, in 4 —5 mm long spikes. Flowering March April, fruits from August - October.
Ecology: Scattered in all types of forest from TEF, TS-EF, to MEBF in altitudes from 600 —
1800 m, preferring moist conditions. Natural regeneration under shade.
Distribution: Found in whole Xishuangbanna, further distributed in Laos and Vietnam.
Uses: Valuable timber used for house building and temple poles (Dai). Fruits are edible. Bark
contains tannins.
Elaeocarpaceae
Predominantly tropical family with 540 species worldwide in South Asia, Australia, South
America. In Xishuangbanna 2 genera with 18 species. Common species include Elaeocarpus
austro-yunnanensis, E. dubius, Sloanea dasycarpa.
Elaeocarpus austro-yunnanensis
Habit: Evergreen tree up to 20 m height. Bole up to 60 cm DBH.
Bark dark brown, deeply fissured. Leaves simple, alternate, spirally arranged, toothed. Dark
green foliage intermingled with scarlet red old leaves. Dimension 10-21 x 5-9 cm. Stalks bent
and swollen at the leafbase. Flowers small, in unbranched sprays, flowering June — Juli. Fruit
ellipsoid 3.5 — 4 cm long, 2 cm wide, green-yellowish, fruiting October — November.
Ecology: Scattered in TS-EF, common in MEBF in altitudes 800 — 1400 m. In MEBF mixed
with Syzygium cumini, Engelhardtia spicata, Lithocarpus microspermus, Sacrosperma
arboreum, Castanopsis spp., more abundant on poorer soils.
Distribution: Common in whole Xishuangbanna. Endemic to Yunnan, further distributed in
Cangyuan, Jingping, Menglian, Simao.
Uses: Timber not very durable, used for boards and interior constructions.
Sonneratiaceae
Tiny family with only 8 species worldwide, confined to tropical Africa and Asia. In
Xishuangbanna 1 species: Duabanga grandifolia.
Duabanga grandifolia
Habit: Huge evergreen tree up to 40 m height. Young trees with long horizontal side branches,
in older trees becoming steeply ascending with drooping tips.
Bark pale grey, not cracked, irregularly flaking in older trees. Leaves 12-25 x 5-10 cm long,
opposite-planar in long flattened sprays, no teeth. Dark green above, grey-green below. Stalks
stout, 0.2 — 0.7 cm. Flower 5 — 7.5 cm, white, in heavy branched clusters at the end of twigs,
flowering March - May. Fruit 2.7 — 4.5 cm, broadly ovate with large star-shaped calyx at base,
splitting into 5 sections, fruiting May — July.
Ecology: Very fast growing pioneer species preferring moist areas in all types of forest.
Common feature after shifting cultivation, at roadsides and streams. Often growing together with
Anthocephalus chinensis, Mallotus spp. Can be planted as a framework species for restoring
forest ecosystems.
Distribution: Common in Xishuangbanna up to 1000 m a.s.l. Widely distributed throughout
Mainland Southeast Asia.
Uses: Although a fast growing tree, the timber is rather valuable. Used for house building by
different ethnic groups.
Anacardiaceae
875 species worldwide, mostly confined to tropical rainforests, centered in Indonesia. 12 genera
with 18 species in Xishuangbanna. Common species are Spondias pinnata, Dracontomelon
macrocarpum, Drimycarpus racemosus, Semecarpus reticulata, Toxicodendron succedaneum.
Spondias pinnata
Habit: Deciduous tree to 20 m height with open crown and slender branches.
Bark pale grey, smooth with rounded knobs, thick; inner bark pink, juicy. Leaves 30 — 40 cm,
odd-pinnate, alternate, 3 — 8 pairs of opposite leaflets, 3 — 11 cm, without hairs, no teeth,
smooth. Flower 0.5 cm, white or creamy yellow, bisexual and unisexual flowers on the same
tree, branched clusters in upper leaf axils, 15 — 30 cm, flowering February — May. Fruit 3.5 —
5 cm, green turning into dirty yellow, oval, fleshy with a single large stone containing up to 5
seeds, fruiting August — December.
Ecology: Found at altitudes 500 — 1200 m, mainly in TS-EF. Very common around villages,
often mixed with bamboo. Planted in homegardens of several ethnic minorities.
Distribution: Common in whole Xishuangbanna, further distributed in Mainland SE-Asia.
Uses: Multipurpose tree. Fruits are edible and very rich in Vitamin C, used for making sauces
and in soups; characteristic flavour of the Dai cuisine. Timber can be used for making boards and
fuelwood. Rubber-like sap can be extracted from the bark.
Rubiaceae
Large and very diverse family with over 10,000 species worldwide, including herbs, climbers
shrubs, and trees. Concentrated in the tropics. In Xishuangbanna about 45 genera with over 120
species. Common tree species include Anthocephalus chinensis, Metadina trichotoma, Randia
yunnanensis, Wendlandia tinctoria.
Anthocephalus chinensis
Habit: Briefly deciduous tree up to 30 m height. Young trees have a long straight trunk with
horizontal side branches clustered at the top. Mature trees develop a large, oval crown with
drooping branches.
Bark pale grey brown, smooth when young, becoming flaky to fissured when old. Inner bark
pale yellow. Leaves 10-30 x 5-14 cm, opposite planar, oblong with slightly pointed tips. Flower
white turning pale orange in dense spherical heads, 4 — 6 cm in diameter, solitary or in pairs at
the end of the twigs, flowering July — September. Fruit 3.5 — 5 cm, green then brown, rather
fleshy, individual fruits splitting into 4 sections with many wingless seeds, fruiting November —
January.
Ecology: Common in TEF and TS-EF, from 500 up to 1200 m. Usually in open areas along
streams and roads. Very fast growing pioneer species, often growing together with Duabanga
grandiflora. Can be planted as a framework species for restoration of degraded forest areas.
Distribution: Fairly common in whole Xishuangbanna, further distributed in Yunnan and
Guangxi, Northern Thailand and Northern Indochina.
Uses: Good timber, used for carpentry and carvings. The species is widely used in plantation
forestry. Also used as a shade tree in agro-forestry schemes, e.g. for Coffea and Cocoa.
Metadina trichotoma
Habit: Evergreen tree up to 25 m height.
Bark yellow-brown, slightly flaking. Leaves 8-24 x 3-8 cm, tapering at both ends, decussately
arranged, dark green and glossy above. Flower heads 1.5 — 2 cm in diameter, pale yellow,
grouped in branched clusters at the end of the twigs, flowering February — March. Fruit heads 1
cm in diameter with small individual fruit splitting into 4(2) sections; unwinged seeds, fruiting
June — August.
Ecology: From 600 up to 1200 (2000) m. Mainly found in TEF and TS-EF in the medium layer
growing together with Chisocheton siamensis, Knema spp., Garcinia spp., Sapium baccatum.
Scattered in MEBF. Prefers moist conditions. Shade-tolerant when young, mature trees are lightdemanding.
Distribution: In Xishuangbanna found in Jinghong and Mengla. Further distributed in Guangxi,
Guangdong, Northern Thailand, Northern Laos and Northwestern Vietnam.
Uses: Valuable timber with yellow colour. Used for house building by the Dai ethnic group.
Myristicaceae
400 species mainly confined to tropical rainforests of SE-Asia. 3 genera with 9 species in
Xishuangbanna. Common species are Knema furfuraceae, K. globularia, Myristica yunnanensis,
and Horsfieldia glabra.
Knema furfuraceae
Habit: Evergreen tree up to 20 m height with narrow pyramidal crown and horizontal branches
with drooping tips.
Bark grey-brown to green-brown, smooth and thin. Inner bark with watery pink sap. Leaves 1550 x 5-14 cm, lanceolate with pointed tip and gradually narrowed towards the heart-shaped base.
Mature leaves leathery, dull dark green above, grey-green below. Stalk 0.7 — 1 cm, stout.
Flower yellow-brown, in short clusters with woody main stalks, mostly behind leaves, flowering
January — February. Fruit 3 — 4.5 cm, oblong, densily covered with yellow-brown hairs, thick
skin. Red seeds, fruiting March — June.
Ecology: The species is a distinctive feature of less-disturbed TEF, usually at lower altitudes up
to 1000 m. Shade-demanding, often dominating in the lower and medium storeys together with
Knema globularia, Garcinia spp., Pittosporopsis kerrii, Baccaurea ramiflora. Scattered also in
TS-EF and MEBF in moist areas and Northern expositions.
Distribution: In Xishuangbanna found in Jinghong and Mengla. Further distributed in Thailand,
Malaysia and parts of Indonesia.
Uses: Fuelwood and timber for small constructions. Seeds contain oil.
Myristica yunnanensis
Habit: Evergreen tree up to 30 m height with conical crown and horizontal branches.
Bark grey-brown, smooth. Inner bark with red sap. Leaves 24-45 x 8-18 cm, lanceolate, dark
green above, grey-green below with tiny reddish hairs. Stalks 2-4 cm. Flower yellow, 3 — 5
individual blossoms in leaf axils, flowering November — January. Fruit 4 — 5.5 cm with
yellow-brown hairs, containing a red seed 3.5 — 4.2 cm, fruiting March — June.
Ecology: The species is confined to TEF up to 700 m. Shade demanding when young, shadetolerant when mature. Preferring moist areas, growing together with Garcinia spp., Knema spp.,
Barringtonia macrostachya, Horsfieldia glabra.
Distribution: In Xishuangbanna distributed in Mengla and Jinghong, further distributed in
Jingping. Endemic to Yunnan.
Uses: Seeds contain oil. Timber can be used for poles and boards. Can be used for afforestation.
Note: Protected in China (class III).
Theaceae
Small but widespread family with 600 species worldwide. 7 genera with 22 species in
Xishuangbanna. Common tree species include Schima wallichii, Eurya groffii, Anneslea
fragrans.
Schima wallichii
Habit: Large evergreen tree up to 35 m height and 1 m DBH with a dense crown and straight
unbutessed trunk.
Bark dark grey or almost black, becoming very thick and deeply cracked. Inner bark dark red,
fibrous and irritating. Leaves variable, 2-8 x 5-18 cm, broadly ovate, mostly without teeth.
Above dark glossy green, without hairs, below light green with short white hairs at the veins.
Young leaves orange, densily covered with silky hairs. Flower 2 — 5 cm, white, solitary or
clustered in the axils of leaves near the end of the twigs, flowering March — April. Fruit 1 —
2.5 cm woody spherical capsule splitting into 5 sections with many seeds surrounded by a
narrow wing, fruiting November — February.
Ecology: Characteristic and common element of MEBF growing together with Castanopsis
hystrix, Lithocarpus truncatus, Paramichelia baillonii, Phoebe puwenensis. More scatteredly in
TEF and TS-EF. The species is a long-lived pioneer with wind-dispersed seeds. Good natural
regeneration and strong coppice ability. It readily establishes in disturbed areas (e.g. over-logged
areas) and often grows into gregarious stands on abandoned shifting cultivation lands.
Distribution: Common in whole Xishuangbanna. Further distributed throughout Yunnan,
Mainland Southeast Asia, Indonesia.
Uses: Wood durable; main house building timber used for poles, beams and boards by many
ethnic groups in Xishuangbanna. Good fuelwood, used by Aini and produced in a coppice
system with standards. The species is fire-resistant and can be planted in fire breaks. Can be
propagated through seedlings and by direct sowing.
Magnoliaceae
223 species worldwide. 5 genera with 11 species in Xishuangbanna. Common species include
Paramichelia baillonii, Manglietia forrestii, Magnolia henryi.
Magnolia henryi
Habit: Small to medium sized evergreen tree up to 20 m height with a narrow crown.
Bark light to dark green, smooth. Leaves 7-20 x 20-70 cm, narrowly elliptic, dark glossy green
above, stalks 3 — 5 cm. Flower buds narrow, 5 — 7 cm long, stalks up to 10 cm, flowering in
May. Fruit woody, oblong, 10 — 15 cm, fruiting August — September.
Ecology: Shade demanding tree, growing scatteredly in the under-storey of different forest types,
mainly found in moist conditions at altitudes from 540 up to 1500 m.
Distribution: In Xishuangbanna found in Jinghong and Mengla, further distributed in Southern
Yunnan, Myanmar, and Northern Thailand.
Uses: Ornamental purposes.
Note: Protected in China (class III).
Lecythydaceae
285 species worldwide, mostly in South America. 1 genus with 2 species in Xishuangbanna:
Barringtonia macrostachya, B. pendula.
Barringtonia macrostachya
Habit: Medium to big sized evergreen tree up to 25 m height. Lower trunk up to 1 m in
diameter. The trunk branches early, dense crown.
Bark grey to pale brown, small rounded flakes on mature trees. Inner bark with light red strips.
Leaves 5-13 x 15-40 cm, dark glossy green, narrowly lanceolate with a short tip, without teeth;
stalks 2 — 4 cm. Flower 1.5 — 4 cm, white to pinkish, hanging in clusters up to 110 cm long,
flowering April — June. Fruit egg-shaped with 4 main ridges, 8 — 14 cm, red to purple colour,
fruiting July — September.
Ecology: Characteristic element of the middle-storey of TEF at altitudes from 580 — 800 m,
associated with Baccaurea ramiflora, Microcos chungii, Alniphyllum fortunei, Knema spp.,
Garcinia spp. The species prefers moist and shady conditions, trees often growing in small
groups. Natural regeneration is good under shade.
Distribution: In Xishuangbanna found in Mengla and Jinghong, further distributed in Yunnan in
Jingping and Honghe.
Uses: Due to branchy growth habit rarely used for house building. Often planted for ornamental
purposes.
Lauraceae
2850 species mostly in SE-Asia and tropical America. 13 genera with 66 species in
Xishuangbanna. Common species include Actinodaphne henryi, Alseodaphne petiolaris,
Cinnamomum bejolghota, Litsea baviensis, Litsea glutinosa, Machilus tenuipila, Machilus
salicina, Phoebe minutiflora, Phoebe puwenensis.
Actinodaphne henryi
Habit: Medium sized evergreen tree up to 25 m height.
Bark yellow-white, smooth. Leaves whorled, 7-13 x 17-30 cm, young leaves are light green
produced in distinct flushes. Terminal buds large, protected by many layers of overlapping leafy
bracts, leaving distinct scars on the twigs. Flower male and female on different trees, flowering
December — February. Fruit 3 — 4 cm, reddish, fruiting August — October.
Ecology: Common and forming a characteristic element of MEBF at altitudes 800 — 1300 m.
Associated with Castanopsis hystrix, C. fleuryi, Lithocarpus spp., Engelhardtia spicata,
Elaeocarpus austro-yunnanensis, Phoebe minutiflora. The species is shade-tolerant when young,
light-demanding when mature. Common in dryer areas of MEBF, also in disturbed areas.
Distribution: Found in whole Xishuangbanna, further distributed in Simao.
Uses: Good wood properties, but small dimensions of timber. Mainly used for smaller
constructions and carpentry.
Machilus salicina
Habit: small evergreen tree up to 5 m with shrubby habit.
Bark dirty white, smooth. Leaves 1.2-3 x 8-18 cm, old leaves dark green and glossy above, light
grren below, young leaves orange to pale red, produced in distinct flushes. Flower yellow, 0.6
cm, flowering February — March. Fruit small, 0.7 cm, red when ripe, fruiting April — June.
Ecology: Very common in the under-storey of dryer MEBF at altitudes 800 — 1400 m, growing
together with Olea rosea, Lasianthus kerrii, Ficus hirta var. imbariensis.
Distribution: Found in whole Xishuangbanna, further distributed in Southern Yunnan,
Guangdong, Guizhou, Guangxi, and Northern Vietnam.
Uses: Fuelwood and ornamental purposes.
Litsea glutinosa
Habit: small to medium sized tree up to 15 m, briefly deciduous.
Bark pale creamy brown or greyish, finely fissured. Inner bark yellow with aromatic resin.
Leaves 3-11 x 6.5-26 cm, alternate, clustered near the end of the twigs, elliptic-oblong with blunt
tip. Young leaves orange, densily covered with yellowish hairs, old leaves dark glossy green
with hairs on main veins above. Flower heads in unbranched clusters in leaf axils, up to 7 cm,
flowering May — June. Fruit 0.7 — 1 cm, black, fruiting September — October.
Ecology: Common in all types of forest at altitudes from 700 — 1900 m. Light-demanding,
prefers open forest areas, widespread after disturbances and on abandoned shifting cultivation
lands.
Distribution: Found in whole Xishuangbanna, further distributd in Southern Yunnan, Guangxi,
Guangdong, and Northern Vietnam.
Uses: Timber with good woo properties, used by the Dai for house building. The resin and seeds
can be used to produce oil.
Bombacaceae
Small family with 250 species worldwide, mainly in tropical America. 1 genus with 2 species
native to Xishuangbanna: Bombax ceiba and B. insignis.
Bombax ceiba
Habit: Big deciduous tree up to 35 m. Large crown with thick horizontal branches.
Bark pale grey or cream, with sharp conical thorns when young, becoming smooth and slightly
fissured with age. Leaflets 4-5 x 8-15 cm, narrowly elliptic or lanceolate, completely smooth.
Individual stalks 1.5 — 2.5 cm, main stalks 10 — 19 cm. Flower 8 — 10 cm, bright orange-red
appearing shortly after the old leaves fall from January to February. Fruit 4-6 x 10-17 cm,
oblong, straight, fruiting March — April.
Ecology: Light-demanding species, grows usually in open areas, often along roadsides at
altitudes from 800 — 1700 m. Tolerant of temporary flooding and often seen along river banks.
Scatteredly in TS-EF and Limestone forest, often as big emergents.
Distribution: Common in whole Xishuangbanna, further distributed in Mainland SE-Asia,
Indonesia and Australia.
Uses: Soft timber, used for making matches. Hairs inside the seeds are used for stuffing quilts
and pillows. Planted in homegardens of several ethnic groups.
Leguminosae
One of the largest plant families which forms an important part of the flora on every continent
with 18,000 species worldwide. Split into 3 groups: Papilionoidae, Caesalpinioidae, and
Mimosoidae. About 30 genera with at least 70 tree species in Xishuangbanna. Common tree
species of the Papilionoidae include Erythrina stricta, Dalbergia spp., Ormosia yunnanensis.
Belonging to the Caesalpinioidae group are Bauhinia variegata and Cassia siamea. Mimosoidae
include Acrocarpus fraxinifolius, Albizia chinensis, Cylindrokelupha yunnanensis, and
Pithecellobium clypearia.
Erythrina stricta
Habit: Medium-sized deciduous tree up to 25 m height with steeply ascending branches and
open crown.
Bark pale cream, soft and corky, young trees with sharp thorns on thick woody bases, older trees
with less thorns, almost smooth. Leaves spirally arranged, pinnately trifoliate18 — 27 cm long,
leaflets thin, 9-11 x 8-14 cm. Twigs robust, prickly. Flower 3.5 — 4 cm, bright scarlet, in dense
clusters, flowering February — March. Fruit 5 — 10 cm, flat, with 1 — 3 seeds spaced
throughout the pod, fruiting March — May.
Ecology: Common in open areas around villages and along streams, often colonising degraded
areas. Scatteredly in TS-EF, found in both dry and moist areas. Light-demanding, natural
regeneration only in open areas.
Distribution: Found in whole Xishuangbanna, further distributed in Mainland SE-Asia, Eastern
Java, and the Philippines.
Uses: Wood very soft. The Dai use the trunk to make pots for steaming rice.
Bauhinia variegata
Habit: Small deciduous tree up to 15 m with open irregular crown.
Bark tan-brown to blackish, roughly cracked. Leaves 5 — 12 cm, circular, 2-lobed with a wide
and shallow cleft. Young leaves silky hairy, old leaves dark green. Flower 7 — 10 cm, white or
purple (wild trees usually have white flowers), in short unbranched clusters along leafless twigs,
covering the whole tree, flowering January — March. Fruit 2-2.5 x 20-30 cm, splitting
lengthways and curling outwards in 2 ribbons, 10 — 25 seeds, fruiting in March — May.
Ecology: Common in TS-EF with longer dry period, especially in limestone forests and in
deciduous forests. Light-demanding tree, abundant in natural regeneration after shifting
cultivation, often associated with Ficus semicordata, Trema orientalis, Mayodendron igneum,
and Cratoxylon cochinchinensis.
Distribution: Common in whole Xishuangbanna, further distributed in Guangxi, Guangdong,
Hainan, Taiwan, and Indochina.
Uses: Good wood properties but timber with small dimensions, used for carpentry. Flowers are
edible and a traditional dish of Dai, Hani and Jinuo ethnic groups. Often planted for ornamental
purposes.
Euphorbiaceae
Large and divers family, 8100 species found on all continents, but most abundant in the tropics.
27 genera with about 90 species native to Xishuangbanna. Common tree species include
Baccaurea ramiflora, Bischofia javanica, Sapium baccatum, Antidesma bunius, Alchornea
tiliafolia, Phyllanthus emblica, Macaranga denticulata, Mallotus spp.
Baccaurea ramiflora
Habit: Small evergreen tree up to 12 m height with dense and spreading crown and crooked
trunk.
Bark pale cream, smooth or slightly flaking, thin. Leaves spirally clustered at intervals along the
twigs, narrowly elliptic with shortly tapering tip, 5-10 x 10-22 cm, dark green and shiny above,
completely smooth. Flower small, pale orange or yellow-green, male and female on different
trees, females on older branches and on the main trunk in drooping clusters up to 30 cm,
flowering February — March. Fruit about 2 — 3 cm, purplish when ripe, ellipsoid, hanging in
strings from older branches and the main trunk, fruiting May — Juli.
Ecology: Main under-storey tree in TEF, growing together with Pseudouvaria indochinensis,
Pittosporopsis kerrii, Ficus langkokensis, shade-demanding, prefers dryer areas in the TEF at
altitudes from 500 — 1000 m.
Distribution: Found in whole Xishuangbanna, further distributed on Hainan, in Guangxi,
Vietnam, India, and Myanmar.
Uses: Fruits are edible and taste sweet-sour, often cultivated in Dai homegardens. The fruits can
be used to cure skin diseases and the bark for curing cough. Wood is used for agricultural tools
and for fuelwood.
Bischofia javanica
Habit: Large semi-evergreen tree up to 35 m height with dense crown and stout trunk.
Bark pale brown or reddish brown, smooth. Inner bark thick, brownish-pink with red sap.
Leaves trifoliate, spirally alternating. Leaflets 4-8 x 7-15 cm, oval-elliptic; margin with small,
rounded teeth, completely smooth. Flower greenish-yellow, numerous in narrow branched
clusters at leaf axils, flowering January — February. Fruit 0.5 — 1 cm, hanging in large
clusters, brown-black when ripe, fruiting July — November.
Ecology: Common along stream valleys in all types of forest at altitudes from 600 — 1200 m.
Often one of the few large trees left standing in degraded forests near villages. Shade-tolerant
when young, light-demanding when mature.
Distribution: Common in whole Xishuangbanna, further distributed throughout SE-Asia,
Taiwan, Southern Japan, Pacific Islands.
Uses: Wood used for construction and furniture. The bark contains tannins and is used by the
Dai for toughening ropes and nets. Fruits are edible. Roots can be boiled to make a soup.
Betulaceae
110 species concentrated in Northern temperate regions. 2 genera with 3 species in
Xishuangbanna: Betula alnoides, Betula luminifera, and Alnus nepalensis.
Betula alnoides
Habit: Large, briefly deciduous tree up to 40 m height with rather open crown and slightly
drooping branches.
Bark red-brown or silvery grey with large oblong lenticels, peeling in very thin horizontal
flakes. Inner bark pale brown, aromatic. Leaves spirally arranged, simple, sharply and irregularly
toothed, lower surface with tiny resinous dots. Flower tiny, greenish, in drooping catkins 10 —
15 cm long. Male and female flowers in different catkins but on the same tree, flowering
December — January. Fruit 0.4 cm with 2 papery wings braoder than the nut, fruiting April —
June.
Ecology: Found in MEBF, usually at higher elevations (800) 1000 — 1700 m. The species
prefers moist conditions, usually common at Northern Expositions, associated with Sapium
baccatum, Litsea baviensis, Alniphyllum fortunei. Long-lived pioneer species, seeds are
dispersed by wind. Abundant in natural regeneration on abandoned shifting cultivation lands or
small clearcuttings, can grow into gregarious stands.
Distribution: Found in whole Xishuangbanna, further distributed in Northern Thailand,
Himalyas, Northern Indochina.
Uses: Valuable timber, used by Dai for house building and carpentry. The bark is used for
medicinal purposes such as curing colds, treating Malaria, and stomach aches.
Guttiferae
400 species confined to the old world tropics. 3 genera with 9 species in Xishuangbanna.
Garcinia xanthochymus
Habit: Small evergreen tree up to 18 m height with single straight main trunk and horizontal
branches.
Bark dark brown, thin. Inner bark with yellow sap. Leaves opposite, up to 10 x 40 cm, rounded
or blunt at both ends, thick, dark glossy green. Flower 1.5 — 2.5 cm, whitish, 4 — 8 flowers
clustered together on short woody stumps, flowering March — April. Fruit 4.5 — 9 cm dark
yellow, 3 — 5 large seeds, fruiting September — November.
Ecology: Shade-demanding under-storey tree in TEF at altitudes 600 — 1000 m, common in
less-disturbed forest, often along streams. The species is associated with Aglaia parviridia
Knema spp., Baccaurea ramiflora, Mitrephora spp.
Distribution: In whole Xishuangbanna, further distributed in Jingping, Hekou, Northern
Thailand.
Uses: Fruits are edible, seeds contain oil, the sap can be used for medicinal purposes. Also used
for fuelwood.
Meliaceae
Almost exclusively tropical family with 565 species. 12 genera with at least 29 species in
Xishuangbanna. Common tree species include Aglaia parviridia, Amoora dasyclada,
Aphanamixis grandifolia, Chisocheton siamensis, Dysoxilum binectariferum, Toona ciliata,
Walsura yunnanensis.
Toona ciliata
Habit: Large, briefly deciduous tree up to 40 m height with long straight trunk with narrow
buttresses when mature.
Bark grey-brown, vertically cracked. Inner bark orange-brown, fibrous, sweet smelling. Leaves
35 — 50 cm, odd- or even-pinnate, leaflets in 6 — 11 pairs, 3-4 x 6-15 cm, completely smooth
when mature. Flower 0.5 — 0.8, white, in much-branched clusters at leaf axils and along leafless
twigs, flowering January — February. Fruit 2.5 — 3 cm, blackish, splitting into 5 sections but
not falling apart, fruiting May — July.
Ecology: Common in TS-EF, characteristic component of the emergent layer, found at altitudes
of 700 — 1200 m. The species is light demanding, prefers moist sites. Growing together with
Nephelium chryseum, Altingia excelsa, Ficus altissima.
Distribution: Found in whole Xishuangbanna, further distributed in Guangdong, Guangxi,
Northern Thailand, India and Myanmar.
Uses: Valuable timber with light red color, used for house building by Dai and Hani. Has
become rare due to selective exploitation. Roots, leaves, fruits, and bark are ingredients in
various herbal medicine mixtures.
Datiscaceae
Minute family with only 4 species worldwide. 1 species in Xishuangbanna: Tetrameles
nudiflora, often placed in a separate family of its own, Tetramelaceae.
Tetrameles nudiflora
Habit: One of the largest forest trees reaching a height of 50 m, briefly deciduous. Open crown,
very long straight trunk becoming strongly buttressed when fully grown.
Bark thin, pale silver-grey, smooth and shiny. Inner bark thick and soft, pale yellow-brown.
Leaves 10-15 x 12-20 cm, simple, alternate, clustered near the end of twigs, broadly ovate or
almost circular, irregularly and bluntly toothed. Flower tiny, greenish, male and females on
different trees, in long drooping spikes near the end of leafless twigs, flowering March — April.
Fruit 0.5 cm, pale brown, many minute seeds, fruiting April — May.
Ecology: Characteristic feature of TEF, usually below 700 m, favouring flat alluvial areas close
to streams, growing together with Vatica xishuangbannaensis, Terminalia myriocarpa,
Chisocheton siamesis, Horsfieldia glabra. Also found in dryer sites on rocks and especially on
limestone outcrops.
Distribution: In Xishuangbanna only found in Jinghong and Mengla, further distributed in
Jingping, Vietnam, Laos, Myanmar, Malaysia.
Uses: Medium timber quality, used for boards.
Note: Protected in China (class II).
Sapindaceae
Large, almost exclusively tropical family, 1450 species worldwide. 10 genera with 11 species in
Xishuangbanna. Common species include Nephelium chryseum, Pometia tomentosa
Mischocarpus pentapetalus, and Sapindus rarak.
Pometia tomentosa
Habit: Big evergreen tree up to 35 m height, with rather open crown and slightly buttressed
trunk.
Bark orange-brown, quite smooth, often flaking in thin scales. Inner bark pale orange with red
sap. Leaves 30 — 70 cm, even-pinnate, 4 — 10 pairs, 3.5-9 x 6-26 cm. Mature leaves bright
green with scattered red-brown hairs. Flower 0.4 cm, orange-green, branched cluster hanging
from upper leaf axils, up to 60 cm, flowering March — April. Fruit 1.2 — 3 cm, bright red,
finally black with a single large seed, fruiting May — June.
Ecology: Found in TEF and TS-EF, restricted to moist areas. Shade-tolerant tree species, but
usually found in the canopy layer. Associated with Parashorea chinensis, Cinnamomum
bejolghota, Horsfieldia glabra, Chisocheton siamensis.
Distribution: Found in whole Xishuangbanna, further distributed in Simao, Jingping throughout
Mainland SE-Asia and parts of Indonesia.
Uses: Good wood properties, used by Dai as a house building timber.
Note: Protected in China (class III).