EFFECTS OF INTENSITY AND FREQUENCY OF CROWN DAMAGE ON RESPROUTING OF ERICA-ARBOREA L. (ERICACEAE)

A clipping experiment was conducted to analyse the effects of intensit y and frequency of crown damage on compensatory responses by resprouti ng in the shrub species Erica arborea. Increased sprout removal (crown damage intensity) promoted recruitment and increased the total dry we ight of new sprout cohorts. Mean size (diameter) of new sprout cohorts was greater under increased intensity or crown damage, although no di fferences in size variability (CV) were obtained. increased crown dama ge events stimulated recruitment of new sprouts, but had no effect on their total dry weight and reduced their mean size. Increased intensit y and frequency of crown damage also promoted growth (RGR) of uncut sp routs according to local position on the lignotuber. The results show that qualitatively different compensatory responses can he obtained de pending on the modular structure of the genet and the frequency and in tensity of crown damage. They also suggest that competition for underg round resources might be important for explaining the interactions amo ng sprouts within the genet. Modular behavior in resprouting species u nder extreme disturbance regimes (e.g. heavy grazing after fire) is al so expected to have a negative effect on overall genet growth and repr oduction. (C) Elsevier, Paris.