Studies on Fire in Scottish Heathland Communities II. Post-Fire Vegetation Development

(1) Post-fire regeneration was studied in experimentally burned stands of species-rich and species-poor heath whose age since burning varied from 6 to 39 years, and also in stands burned in earlier fires. (2) Regrowth of Calluna vulgaris and Erica cinerea declined with preburn stand age, with a switch from mostly vegetative growth in young stands to regrowth mainly from seed in older stands. (3) Where Vaccinium myrtillus was present before the fire it reappeared in abundance after the fire and attained dominance where Calluna vulgaris regrowth was slow. In the absence of rapid regrowth of Calluna vulgaris, Deschampsia flexuosa also spread quickly, both vegetatively and by seed produced after the fire. (4) In species-rich heath the numbers and abundances of grass, forb, and lichen species reappearing declined with preburn stand age; there was little grass or forb regrowth in older stands. (5) These trends were still evident 8 years after a fire, and it was concluded that the floristic composition set up immediately after the fire is the main determinant of post-fire development. (6) The result of burning very old stands is extremely slow regrowth, reduction in species diversity and persistence of bare ground for many years after the fire.