Litter Fall in a Guatemalan Primary Forest, with Details of Leaf-Shedding by Some Common Tree Species

(1) Litter was collected on two plots (20 x 50 m) in an undisturbed rain forest at 900-1100 m altitude on the northern border of the eastern Guatemalan highlands over a period of 2 years. One plot was near the ridge of a hill, the other in the centre of a slope. There were ten 1-M2 litter traps on each plot. (2) The total annual litter production was between 910 and 1150 g m2 yr'1. Compared with other tropical forests, this value is unusually high. Leaf litter comprised 67-77%4 of the total. There was a significant difference between leaf litter production in two consecutive years. The main leaf fall took place during the dry season between November and May, rising towards its end and continuing into the beginning of the rainy season. (3) Leaves of 189 plant species were captured in the litter traps; of these, 105 were trees. The number of plant species whose leaves were found in the traps varied at different times from thirty-eight to ninety-seven. The number of species was highest during the main season of leaf fall. (4) Leaves of thirty tree species were encountered in the litter traps in sufficient numbers to measure their relative abundance. The patterns of leaf-shedding were species-specific and varied from markedly seasonal to nearly continuous shedding with small seasonal fluctuations. Maximum leaf-shedding of these species was mostly between November and May.