Mast seeding, the intermittent production of synchronized seed crops among plant populations, is a world-wide phenomenon that has been reported in the Himalayan mountains across a large number of habitat types, and among a wide variety of long-lived grass, shrub and tree species. In this paper, we review various hypotheses that explain why mast seedling occurs, and describe a number of the better-known mast seeding floral elements that exist in Bhutan. We also stress the need for further documentation of the seeding cycles of plants in Bhutan, and emphasize the need for careful management of species that rely on mast seed crops for their regeneration.