Notes on Agrostis vinealis

Agrostis vinealis Schreb. (Poaceae) is a somewhat poorly known species. Its total distribution and extent of intraspecific variability require further clarification though the species (as A. stricta) has been treated adequately in Widén, K.-G. 1971: The genus Agrostis L. in eastern Fennoscandia. Taxonomy and distribution. Flora Fennica 5: 1-209. A showy morph with yellowish panicle, also mentioned by Widén, has once been found by me in Lohja. Most probably it represents a minor mutation without essential taxonomical relevance.
    In some southern Finnish localities (Lohja, Vihti, Kauniainen, Vantaa) I have observed another morph which might be taxonomically more interesting. As compared with A. vinealis (as it occurs in the rock outcrops of southern Finland), the deviating morph is somewhat smaller in all parts, the subterranean stolons are shorter and thinner,  the stems and leaves are less stiff, the leaf sheaths are usually retrorsely aculeolate and hence slightly rough, the veins of the upper side of the leaves are fewer and hence the lamina hardly gets inrolled in drying, the upper leaf surface is often short hairy, and the inflorescence always lacks anthocyanin colour. The anthers are usually dehiscing with seemingly good pollen. Sometimes the plant reminds of the closely related species A. canina. In the siliceous rock outcrops, this deviating morph plant occurs in a certain microhabitat: the lower terraces, shelves and basal parts of steep walls. These habitats are more or less shady because of surrounding woods. Typical A. vinealis favours more or less open, sunny and windy rock surfaces.
    The habitat requirements of typical A. vinealis and this deviating morph appear different to such a degree that I have not seen them growing side by side. It remains to be studied whether these deviating plants represent an independent taxon or solely represent modifications adapted to the more shady habitat

Created August 29, 2004.