DRY-MATTER ECONOMY AND REPRODUCTION OF A TEMPERATE FOREST SPRING GEOPHYTE, ALLIUM-URSINUM

For a natural population of Allium ursinum age states are defined on the basis of morphological criteria. Differences in the dry matter economy of these age states illustrate the underlying life history. Most seeds rest several years in dormancy after maturity. It takes on average more than 6 yr until juvenile plants attain the dry matter threshold level for the production of an inflorescence. Flowering plants divert 41% of their dry matter gain during spring to reproductive parts (7% to the seeds). Since flowering plants show a marked negative annual dry matter balance, c. 81% of them are not able to flower again the next year. At the same expense of carbon reserves the formation of daughter bulbs results in a considerably higher number of new ramets than the production of seeds. Nevertheless, the investment in seed production is extraordinarily high in relation to other woodland perennials. This might be explained by the lack of an effective dispersal of the daughter bulbs. By vegetative propagation dense groups of adult ramets develop, which will finally undergo mutual shading.