Disturbance-based restoration for recovery of pitch pine (Pinus rigida) in the Thousand Islands Ecosystem: a comparison of prescribed fire and mechanical disturbance on seedling regeneration

Disturbance plays an important role in maintaining forests worldwide. Many natural disturbance regimes, especially wildfire, have been modified, which can lead to the loss of disturbance adapted forest communities. Pinus rigida (pitch pine) is strongly associated with wildfire in the core of its range, however the association becomes less certain towards the species’ range margins. I tested the efficiency of a prescribed fire and mechanical disturbance treatment on increasing P. rigida seedlings using a Before-After Control-Impact (BACI) design at two sites at the northeast range margin of P. rigida in the Thousand Islands Ecosystem, Canada. Fire had the greatest effect on regenerating P. rigida seedlings and mechanical treatments were ineffective. My results suggest that the use of prescribed fire is the best approach to increase P. rigida seedlings in the Thousand Islands Ecosystem, possibly because these populations are exhibiting phenotypic plasticity in traits that favour conditions created by fire.