In the mind of a natural scientist, forests are living organisms consisting of plants trees, bushes, shrubs, grasses, floor mosses and lichens. The undergrowth serves as a indicator of the fertility of a forest and helps classify it. Finland has developed a Cajander-like system, where forest types are separated based on the vegetation of the forest floor. Stands and copses are also classified according to the forest types that are most similar in ecological terms.
Forest types from top to bottom: cowberry-type forests, heather-type forests, lichen-type forests
Virttaankangas belongs to the forest vegetation zone of south-west Finland, which is a very favourable area for vegetation. However, on the ridge, the variety of vegetation is lower due to its poor soil and despite the appearance given by lichen coverage. Due to the sandy soil of the ridge, lichen type and heather type forests are more abundant than coniferous forests on average.
The ridge’s coniferous forest can be divided into three main groups and then into several subgroups by their species:
In the cowberry semi-dry coniferous forest there are only three species of shrub: cowberry (Vaccinium Vitis-idaea), wavy hair-grass (Deschampsia fl exuosa) and heather (Calluna vulgaris). The most abundant of ground layer species are rugose fork-moss (Dicranum polysetum) and the less common red-stemmed feathermoss (Pleurozium schreberi).
In the heather-type dry forest, the shrub layer is sparse and mosses are much abundant than the lichens on the ground layer, of which red-stemmed feathermoss (Pleurozium schreberi) is found more abundantly than rugose fork-moss (Dicranum polysetum).
In the more barren lichen-type dry forest it is reideer lichen that forms large mats on the forest floor. On the layer above heather and cowberry are common and crowberries (Empetrum nigrum) and bearberries (Arctostaphylos uvaursi) are also found. Mosses are much less common but red-stemmed feathermoss and rugose fork-moss are found.
Photos: Tuuli Lunas ja Juha Kääriä