OV25: Urtica dioica-Cirsium arvense community

Summary

Constant species

Cirsium arvense, Urtica dioica.

Physiognomy

The Urtica dioica-Cirsium arvense community typically has a rather open or patchy cover of U. dioica, usually grown tall by mid-summer but not so densely developed as to exclude other associates. Among these companions, large thistles and coarse grasses are the most conspicuous, with Cirsium arvense and C. vulgare both occurring frequently, and often in some abundance, and Dactylis glomerata, Elymus repens, Holcus lanatus and Arrhenatherum elatius very common in various of the sub-communities. Galium aparine is occasional, its shoots sprawling over the taller herbs, and there can be scattered plants of Lamium purpureum, Leucanthemum vulgare, Epilobium hirsutum and Carduus acanthoides.

Sub-communities

Holcus lantus-Poa annua sub-community. Elymus repens and Holcus lanatus with, somewhat less frequently, Poa annua and Agrostis stolonifera give a distinctly grassy look to this vegetation and there is often some Sonchus asper, S. oleraceus, Senecio vulgaris, Daucus carota, Rumex obtusifolius and Echium vulgare. Locally, Pteridium aquilinum can figure. Smaller associates in more open places among this tall and coarse herb cover include Cerastium fontanum, Trifolium repens, T. pratense and Myosotis arvensis and Vicia sativa is an occasional climber.

Rumex obtusifolius-Artemisia vulgaris sub-community. Elymus repens, Dactylis glomerata and Arrhenatherum elatius are frequent here, along with the nettle and thistles, but the most distinctive feature is the common occurrence of Artemisia vulgaris and Heracleum sphondylium with occasional Calystegia sepium, Malva sylvestris and Conium maculatum.