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Ba Na Nature Reserve 1996
5.3 Other vegetation types present
A number of other vegetation types were represented in the Ba Na region which were not the
subject of forest transect studies; these are listed below.
5.3.1 Plantation
The lower slopes of Ba Na mountain and surrounding lowlands are dominated by Eucalyptus
camandunensis plantations, with other tree crops such as jackfruit (Artocarpus heterophyllus) and
Acacia mangium also being grown. The ground flora of these plantations was limited to pioneer
shrubs such as Mallotus spp. Where this scrubby flora had been cleared to allow grazing of
livestock, Mimosa pudica and grasses were dominant. At the edges of the Ba Na reserve, natural
secondary forest is still being cleared to make way for Eucalyptus plantations.
5.3.2 Pioneer growth
Where forest growth had been totally cleared, pioneer vegetation consisting principally of shortlived
shrubs and climbers had grown up. Common shrubs included Mallotus barbatus,
Macaranga sp., Rubus spp., Melastoma candida and Clerodendron paniculatum. Occasional trees
of Cassia siamea are also present. In many places the herbaceous climber Pueraria montana
(Fabaceae) grew over shrubs and into the crowns of trees at the edges of secondary forest.
Pioneer vegetation dominates the young Eucalyptus plantations and cleared areas along the edge
of the reserve, and P. montana and other pioneer species are also found in smaller clearings
throughout the forest.
5.3.3 Montane Rain Forest
At heights of around 1300m and above (to near the summit of Ba Na mountain at 1440m), the
dominant vegetation is montane rainforest, containing many genera not represented elsewhere in
the Ba Na forests. Conifers such as Podocarpus spp. are common. Other important families in
this forest formation are the Fagaceae (including genera such as Quercus), and Lauraceae.
Typical lowland rainforest genera, such as Dipterocarpus (Dipterocarpaceae), are absent.
Unfortunately, the steep nature of the slopes on which this forest is found meant that it was not
possible to study a vegetation transect in the montane forest proper, but a site which was
intermediate between the montane and lowland forests was selected (Forest Transect 3, see
above).
5.3.4 Montane Grassland
The plateau at Ba Na summit was cleared of forest using herbicides in the mid to late 1960s, and
is still treeless. Grasses predominate, although there are also a number of alien weedy species,
originally garden escapes from the grounds of villas built here during the French period; these
include dandelion (Taraxacum officinale), strawberries (Fragaria sp.), Lantana camara,
Gladiolus sp., and montbretia (Crocosmia sp.).
5.3.5 Primary Forest
It appears unlikely that any undisturbed primary forest exists in the Ba Na forest reserve or its
immediate vicinity. Even at high altitudes on the slopes of Ba Na, logging has taken place since
the French colonial period. This cutting has often been small-scale and patchy, and, in recent
times at least, selective in the species removed. There is therefore the possibility that small areas
of forest remain in a condition similar to that of untouched primary forest, but no such areas were
discovered over the period of Frontier phase VN9503.
Frontier- Vietnam Environment Research Report 7 13