Constant species

Agrostis stolonifera, Myosotis arvensis, Poa annua, Poa trivialis, Polygonum aviculare.

Physiognomy

Poa annua and P. trivialis are constant in the Poa-Myosotis arvensis community and the former in particular can have high cover. Agrostis stolonifera and Elymus repens are also very frequent overall and, among these grasses, are scattered plants of Polygonum aviculare and Myosotis arvensis. Other common associates include Stellaria media, Chamomilla suaveolens, Ranunculus repens, Veronica persica and Anagallis arvensis. More occasional are Lamium purpureum, Bilderdykia convolvolus and Lolium perenne.

Sub-communities

Typical sub-community. Polygonum persicaria and Sonchus asper are rather more frequent here with occasional Urtica dioica, Dactylis glomerata, Lolium multiflorum, Chenopodium album and Atriplex patula.

Dicranella staphylina-Bryum sub-community. Among vascular plants, Aphanes arvensis and Veronica arvensis become frequent in this sub-community with occasional Lapsana communis, Viola arvensis, Heracleum sphondylium and Trifolium repens. However, the more striking feature over the surface of the soil is the variety and abundance of diminutive acrocarpous mosses. Dicranella staphylina, Phascum cuspidatum, various Bryum spp. (including B. rubens, B. erythrocarpum, B. microerythrocarpum, B. violaceum and B. klinggraeffii) are frequent with occasional Pottia truncata, P. intermedia, Barbula convoluta and B. unguiculata.

Habitat

The Poa-Myosotis community is characteristic of trampled and dunged areas within damp leys, pastures and recreational swards. In such situations, P. annua germinates very readily where seeding has been poor or where trampling creates gaps. Its seed remains viable in the dung of cows and horses and can germinate in cattle dung (Hutchinson 1979).