“….. to see these plants in all their health and vigor was a sensation I shall never forget – one of those which we experience but rarely in a whole lifetime!...”
- F.W. Burbidge, 1880
Due to the wide range of altitude, from ~500 – over 4000m, Kinabalu Park has essentially four main vegetation zones. Within each main zone however there are localized variations depending on factors such as soil type, terrain, presence or absence of soils, proximity to streams and degree of exposure to sunlight. At altitudes above 1200 m, Kinabalu is a meeting place for plants of Himalayan and Chinese genera and for plants of Australian and New Zealand and even American affinity. They consist of, among others, buttercups (of Australian affinity), the Rosaceous trees and shrubs and Violets (both of which are of Sino-Himalayan affinity) and they mingle with pitcher plants (Nepenthes) and bamboos of Bornean origins.
Lowland Dipterocarp Vegetation
Up to about 1200m (4000 feet), the tropical rain forests dominated by species in the Dipterocarpaceae family could be found. Stratification is visible in this zone to some extent where the dipterocarps grow to heights of over 50m forming the canopy and other smaller species form subsequent layers. They yield seeds which have two or more wing-like structures which help them disperse by wind action. Dipterocarps flower once in three or four years. However, once every ten years or so most of the dipterocarps bloom all at once thus giving the entire forests a kaleidoscope of colors. This phenomenon is known as mega or mass flowering.
There is also a variety of wild fruit trees ranging from the commonly found rambutans, mangoes, durians and figs to the unusual taraps (Artocarpus odoratissimus) which is jackfruit-like and mawang (Mangifera pajang) which tastes like a mango. Common in the lowland forests are plants from the families of palms (Arecaceae), gingers (Zingiberaceae) and bamboos (Graminae). Over 52 species of palms from 10 genera and 30 species of Zingiberaceae have been recorded within the confines of the park. Six bamboo species are found within the Park and four just outside its limits. Many rattan species can be found in these forests.
Kinabalu Park has documented more than 608 species of ferns, where the figure exceeds the number of species found in the entire mainland Africa. Ferns are ubiquitous in all four climatic zones of the Park and take various forms: tree ferns, shade ferns, thicket ferns, epiphytic ferns and tiny scrub ferns etc. Some very notable fern species in this zone are the bird’s nest fern (Asplenium nidus) and tree ferns (Cyathea spp.). In lowland forests of Kinabalu, the largest mosses in the world (Dawsonia spp.) can be seen.
The lower elevations of Kinabalu are also home to numerous species of orchids. John H. Beaman and Reed S. Beaman eminent botanists who had contributed much to the knowledge of Kinabalu flora estimated that there are more than 1000 species of orchids in 121 genera within the Park. Again, both epiphytic and terrestrial orchids are found at all altitudes. Some of the noteworthy species occuring at low elevations are the slipper orchid (Paphiopedilum rothschildianum) which is endemic to Mt. Kinabalu, bamboo orchids (Arundina spp.), the necklace orchid species (Coelogyne spp.), yellow-flowered Spathoglottis spp. and the world’s smallest orchids of the genus Podochilus.
The genus Rafflesia consisting of 14 species are very rare tropical plants found in Borneo, Peninsular Malaysia, Thailand, Philippines, Java and Sumatra. The Rafflesia named after Sir Stamford Raffles who founded Singapore in 1819 is the largest flower in the plant kingdom. Two species (R. keithii and R. pricei) have been found in Kinabalu in the Poring Hot Springs area. A third species, R. tengku-adlini is known from the nearby eastern slopes of the Trus Madi Range.
Lower Montane Vegetation
From about 1200m (4000 feet) to 2000m (6500 feet) the trees are shorter in stature and oak-chestnut forests dominate. Deciduous trees typical of temperate lands such as those from the family of oaks (over 40 species), chestnuts, myrtle, laurels, eucalyptus and the theaceae (tea) are found in this zone. There are also some conifers.
Ferns too are common in this zone and the broad-leafed fern Dipteris conjugata is very characteristic. It forms a link between the primitive ferns and more complex higher plants. Another strange plants in this zone is the celery pine (Phyllocladus hypophyllus), an ancient plant that has stems flattened like leaves and the true leaves reduced to tiny scales. In lower montane forests, the orange-barked Tristania trees stand out from the myriad of other species.
Kinabalu is the richest place in the world for the tropical pitcher plant, Nepenthes. Ten out of 36 species in Borneo are found in the Park. They are found mainly in the lower montane zone although some species are biased towards the upper montane forest. The most striking part of the pitcher plant is the colorful cup which although it appears as a part of the flower is actually a part of the leaf modified to trap insects to obtain nutrients. The largest of the pitcher plant is the Nepenthes rajah. Spencer St. John reported finding the largest pitcher of the largest species, Nepenthes rajah, from Kinabalu containing nearly 4 liters of liquid. Nepenthes endemic to Kinabalu are the N. burbidgeae, N. villosa and N. rajah. Way back in 1859 Botanist J.D. Hooker said: "This wonderful plant is certainly one of the most striking vegetable productions hitherto discovered and in this respect is worthy of taking place side by side with the Rafflesia arnoldii."
Upper Montane Vegetation/ Cloud Forest Vegetation
This zone lies between 2200m above sea level to 3300m (11000 feet). The trees are stunted (less than 6m tall) and their trunks and branches as well as leaves are draped with lichens (especially Usnea spp.), mosses and liverworts. Thick mists swirl and drift in tandem with the wind.
In this zone many species of Rhododendron predominate. Out of 50 species found in Borneo 26 grow in Kinabalu of which five are point endemics (endemic to Kinabalu). Rhododendrons thrive in places which are cool and moist. Most of their flowers are bell-shaped and each of the plants bears many flowers. Their colors are bright and are often red, scarlet, pink, yellow, orange and/ or white and stand out well in the mist-shrouded montane forests. The most notable species in this zone is R. lowii with its sunshine yellow flowers. With altitude the size of the plants and also the flowers shrink and smallest species (also a point endemic), R. ericoides, is found in the highest altitudes.
Above ~2600m, the strange gnarled forms of Leptospermum and Dacrydium transform the forest into fairyland. The sparkling white flowers of Schima brevifolia are very characteristic to the zone. These plants can tolerate the ultrabasic soils thus underlies the trails.
The sub-alpine vegetation starts from 3300m (11000 feet) where the granite core of the summit begin and reaches up to the summit. The trees are gnarled and grotesque. Stunted Leptospermum and Rhododendron ericoides occur in depressions. Towards the higher end of the sub-alpine zone the stunted trees give way to herbaceous plants and grassy meadow-like vegetation dominated by potentillas, buttercups, eyebrights and gentians. In some parts of the mountain, mosses, sedges, orchids and grasses take over the landscape which looks similar to the meadows commonly in temperate lands.
In the summit plateau where the rock face is bare nothing grows except where a thin layer of soils accumulate cracks and crevices. In such nooks and corners hardy tiny mountain orchids and ferns found a root-hold. The tree line here is determined not by altitude but by whether soils are present. The fierce winds and the heavy torrential rains make it almost impossible for most of the plants to survive higher than 3700m (12 200 feet) which is close to the summit.