Shift of conifer boreal forest to lichen-heath parkland caused by successive stand disturbances

In the southern boreal forest (Québec, Canada), tree harvesting is a major disturbance affecting the dominant black spruce (Picea mariana) stands al-ready suffering from naturally recurrent insect and fire disturbances. Although recovery of the spruce forest after an insect infestation or a fire is possible under current site conditions, it is less likely when both types of disturbance occur during a short pe-riod of time. The addition of yet another distur-bance, such as tree harvesting, can thus have cata-strophic consequences. We analyzed the impact of three successive disturbances—tree harvesting, in-sect infestation, and fire—on the regeneration of boreal spruce–moss forests within a period of ap