FW3B Phragmites australis – Agrostis stolonifera swamp
Vegetation
This is a somewhat mixed and often open swamp community. Phragmites australis, Bolboschoenus maritimus and Agrostis stolonifera are the constant species. Frequently accompanying them is the tall swamp species Typha latifolia with Schoenoplectus tabernaemontani occasionally present. With Agrostis in the rather sparse understorey may be found Juncus articulatus, Eleocharis palustris, Hippuris vulgaris, Mentha aquatica, Galium palustre, Lythrum salicaria, Iris pseudacorus or Ranunculus flammula.
Ecology
These stands occur in mildly eutrophic, quite base-rich waters. They have predominantly been recorded from the margins of coastal lagoons, but also from estuaries and from mesotrophic lakes further inland.
Sub-communities
No sub-communities are currently described.
Similar communities
Bolboschoenus maritimus is also a key species in the SM6A Bolboschoenus maritimus – Agrostis stolonifera saltmarsh-swamp. However, in that community Phragmite australis is rare and Bolboschoenus forms dense beds, often accompanied by at least one other halophile, such as Aster tripolium, Triglochin maritimum or Glaux maritima. Dense beds of Phragmites may be referred to the FW3E Phragmites australis – Equisetum fluviatile swamp.
Conservation value
Stands may occur fringing lagoons corresponding to the priority EU HD Annex I habitat 1150 Lagoons*. It is a relatively diverse swamp type (species/4 m2 = 10.6, n = 18).
Management
Occasionally, Phragmites beds are cut for reeds, but those in this community may be too sparse for this to be practical. This vegetation may be threatened by eutrophication and drainage.