We studied the allocation of energetic compounds before flowering in four species of Nothofagus in South Central Chile to determine the individuals that were more likely to flower. Several individuals of N. obliqua, N. alpina, N. dombeyi and N. nitida were categorized according to the amount of starch, total soluble carbohydrates and total proteins stored in the medullar tissue (the pith) before flowering. Categories ranged from I (0 to 25%) to IV (75% to 100%). Most individuals that actually flowered previously accumulated a considerable amount of starch and fitted into categories III and IV. Deciduous species had a large accumulation of energetic compounds early in the year (categories III and IV), but before flowering resources decreased (categories I and II). The opposite was observed in evergreen species. Finally, total proteins slightly increased during autumn and winter, probably induced by the low temperatures during these periods.