SUMMARYThe influence of different light intensities on the vegetative growth and CO2‐exchange characteristics ofCirsium palustreandGeum urbanumwere studied in order to give a possible explanation for the different behaviour of the two species in the ash coppice cycle. The shade avoiding speciesC. palustreshowed shade tolerant characteristics, whereas the species which avoids exposed conditions,G. urbanum, grew well in full daylight. Although there were some minor differences between the two species, the influence of light intensity on vegetative growth gives no sufficient explanation for the observed phenomena in the coppice cycl