The Sacred-Groves which have been preserved since time immemorial, are in sharp contrast to their surrounding grasslands. These groves are generally rimmed by a dense growth of Castanopsis kurzii trees, forming a protective hedge which halts intrusion of Pinus kasia (Khasi Pine) which dominates all areas outside the sacred groves. The heavily covered grounds have a thick cushion of humus accumulated over the centuries. The trees in every sacred groveare heavily loaded with epiphytic growth of aroids, pipers, ferns, fern-allies and orchids. The humus-covered grounds likewise harbour myriad varieties of plant life, many of which are found nowhere else.

One of the most celebrated sacred-groves of the State is the grove at Mawphlang about 25 kilometres off Shillong. This particular grove has for long years been a reservoir of interest for eminent and internationally known botanists.

The sacred-groves which make a unique contribution to the flora of the State are undoubtedly of immense interest to all naturalists.