A forest out of time
At 2,565 meters, the summit of Doi Inthanon is the highest point in Thailand and hosts an ecosystem found nowhere else in the country. This is a true cloud forest, perpetually shrouded in mist, with a cool climate where average daily temperatures hover around 10-12°C. Here, near the peak, exists a rare sphagnum peat bog, a living remnant from a cooler geological period. The bog is a feature of the Ang Ka Nature Trail, a 360-meter-long boardwalk that allows visitors to walk through this primeval environment.
The foundation of this ecosystem is Sphagnum moss, a genus of bryophyte that thrives in the waterlogged and acidic conditions. The moss acts like a giant sponge, creating the bog by retaining vast amounts of water. This creates a low-oxygen environment that dramatically slows decomposition. As layers of dead moss and other plant matter accumulate, they form peat. Scientists have analyzed peat cores from this bog, revealing a local environmental history stretching back at least 4,300 years. Analysis of preserved pollen grains within these peat layers allows researchers to reconstruct past vegetation and climate, indicating that an upper montane rain forest has dominated this area for millennia.