Laggs can develop and be restored inside a raised bog

The lagg is an integral part of the hydrological system of a raised bog and can add significantly to the biological diversity of the ecosystem. Conservation and restoration of raised bogs should therefore involve this transition zone. The ideal situation for conservation is to protect or restore the natural laggy at the outside margin of the bog. However, it is not always possible to restore the lagg where it was historically situated. An analysis of historic maps of a raised bog in British Columbia, Canada, shows that in areas where the outflow of water from the bog has been impeded, lagg plant communities have naturally colonized parts of the bog that were historically open bog. This suggests that it is possible to create the ecohydrological conditions of a lagg in areas that are currently occupied by bog species. Based on this knowledge and the hydrochemical, hydrological, and vegetative characteristics of a regionally-specific laggy reference ecosystem, we describe several laggy restoration options for locations where it is not possible to restore the lagg at the outside margin of the bog