Successful Re-establishment of a Native Savannah Flora and Fauna on the Site of a Former Pine Plantation at Constance Bay, Ottawa, Ontario

Résumé

To determine the extent of successful restoration of native savanna vegetation at The Sandhills, an unusual and biodiversity-rich habitat in the Ottawa Valley, we gathered information from quadrats along transects so as to compare a restored clearing with the surrounding plantation. We provide an indication of success with respect to amount of effort and provide an example of some considerations and procedures for estimating success. With a minimum effort of tree cutting and bulldozing, removal of pine duff and litter, that is estimated to have required five people over a period of less than two weeks, a hectare was successfully restored to pre-settlement savannah vegetation. Apart from a limited seeding effort following the removal of planted trees, the re-establishment of native vegetation proceeded naturally, and it was likely aided by dispersal of seed from adjacent remnant vegetation along paths and firebreaks in the vicinity. Biodiversity, based on number of species and various indices, was substantially greater in the restored clearing than in the adjacent Red Pine platation. The semi-open Jack Pine plantation accommodated species of both shaded and open habitats and diversity approached that of the clearing. However, some species such as blueberry were in poor condition in the plantation, generally not producing flowers or fruit. In addition the non-dominant vegetation was much less of the cover. In the restored area there were more regionally rare species and much greater development of flowering herbaceous species and shrubs. Orthopteran insects, a useful indicator group of plant feeding species, had much higher diversity and abundance in the restored area. Savannah and natural sand barren that have been largely destroyed by plantation forestry can be restored successfully and inexpensively, and there is thus no reason why such restorations should not include large areas and be implemented widely. Among the tools for evaluating success are historical descriptions and various measures of biodiversity and vegetation condition.