What kinds of dunes can you see along the way?
Dunes are formed when sand is moved by the wind. As the wind carries the sand, it gradually accumulates into dunes. The development of dunes can be divided into five stages: embryo dunes, white dunes, grey dunes, crowberry dunes, and forested dunes.
The different stages of dune development can be recognised by their distinct vegetation. The first plants to colonise the sandy shore and the foredunes must be able to withstand salt water, strong winds, being buried by sand, and occasional heat. Typical species of embryo dunes include sea sandwort (Honckenya peploides) and lyme grass (Leymus arenarius). As embryo dunes grow higher and become more continuous, they develop into white dunes. On the white dunes, pale sand accumulates amongst the lyme grass. As the amount of lyme grass decreases and wavy hair-grass becomes more common, the dunes gradually develop into grey dunes. On the sheltered side of the foredunes, sand-tolerant grasses, herbs and mosses begin to establish themselves. These include narrowleaf hawkweed (Hieracium umbellatum), sheep’s sorrel (Rumex acetosella), and fire moss (Ceratodon purpureus). Gradually, they spread to form a continuous carpet of vegetation over the dunes. At Vattaja’s grey dunes, beach pea is particularly abundant. Grey dunes covered with lichens are rare because they are easily worn away or burnt. The grey dunes are followed by the crowberry dunes. Eventually, shrubs and deciduous trees find their way on the dunes and they develop into pine-dominated heath forests.
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