The production of leaves, inflorescences, and growth rates were measured during 1985 for 547 plants of Espeletia barclayana, a giant rosette species in the high Andes of Colombia. There were differences in leaf production between individuals of different sizes, with a maximum for plants 61-90 cm in height (27.9 leaves yr −1 ) and a minimum for plants less than 30 cm (5.1 leaves yr −1 ). For plants more than 61 cm in height there was a minimum in leaf production during February, coinciding with the minimum in rainfall, and also during June coinciding with a decrease in rainfall, low temperature, and a peak in fog and condensation. There was a great variation in the number of reproductive plants from one year to the next (...)