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Beck, E; Schlütter, I; Scheibe, R; Schulze, ED: Growth-rates and population rejuvenation of East-African giant groundsels (Dendrosenecio-keniodendron), Flora, 175, 243-248 (1984), doi:10.1016/S0367-2530(17)31443-3
Abstract:
The most striking feature of the alpine vegetation of the East African mountains is manifested by the tree-like groundsels. The lack of annual rings in the wood of these plants renders the estimation of age and growth rates difficult. Whereas such data have been calculated with respect to unbranched, i.e. pre-flowering, specimens, the present study presents the first determination of the growth rates of branched, i.e. post-flowering, adult plants. The rate of stem elongation was found to be dependent on the age of the plants. Whereas unbranched specimens elongate slowly (3 cm/year), the growth rate nearly doubles subsequent to the first anthesis and then falls off with increasing age. The potential for population rejuventation was also investigated. Of approximately 0.5 × 106 seeds per inflorescence, 54% were anatomically intact, but only 30% of these (equivalent to 18% of the total number) proved capable of germination. In the field less than 1 % of the seeds are found as young plants 3 years subsequent to their production.

Letzte Änderung 24.06.2020