Presqu'ile Provincial Park is a park in southeastern Northumberland County on the north shore of Lake Ontario near the town of Brighton in Ontario, Canada. The park occupies an area of 9.37km2. The name of the park is the French word for peninsula, or literally "almost island", and was believed to be named by Samuel De Champlain on his second expedition. The park area was formed when a limestone island was connected to the mainland by a sand spit; this kind of formation is referred to as a tombolo.Nature and ecologyThe park's wetlands are one of the larger wetlands along the north shore of Lake Ontario, and are noteworthy for the many sand ridges running through them, which increases habitat diversity. The mixture of sand dunes, marshes and forests leads to very high plant diversity.In some ways, the flora of this site is therefore similar to the much larger sand spit at Long Point. The long sand spits in Presqu'ile also create natural vegetation gradients from sand dunes and pannes to coniferous and deciduous forest. Sand dunes and pannes are uncommon along the north shore of lake Ontario. Pannes are an unusual moist sand habitat, calcareous and seasonally flooded, similar to a wet prairie or wet meadow. This creates situations with high plant diversity. The pannes support many unusual plants, such as Carex aurea, Cladium mariscoides, Scleria verticillata, Parnassia glauca and Physostegia virginiana. The colourful pink flowers of the Physostegia are a good indicators of panne habitat during the summer. Because of their scarcity and scientific importance, these wetlands have been used to develop and test general models for factors affecting diversity in plant communities. In drier conditions, these pannes grade into more typical sand dune vegetation. In wetter conditions, they grade into rich marshes and sedge meadows, which intergrade with forested sand ridges in the "Fingers". This rare and distinctive vegetation type is not mentioned in the park's resource management plan., and has been damaged in the past by factors such as road construction, mowing and planting of exotic tree species.