Floristical and ecological properties for identifying of primeval forests in Estonia

True primeval forests in Estonia generally occur as isolated small patches while only a few larger forest stands still remain, mainly in some protected areas. All the surviving primeval forests have many characteristics in common, e.g., the abundance of hemerophobic vascular plant, lichen, bryophyte and fungus species, the high diversity of the biota in general, and the abundance of coarse woody debris. In 1994 we started to study primeval forests of Estonia and developed a ten point scale to estimate the status of a forest to decide whether it can be classified as a primeval forest or rather as another category of forest stand. Of the surviving primeval forests all the larger stands and some of the smaller ones must be protected if they still support sufficiently large numbers of rare species and hemerophobic species specific to primeval forests.