Sea Arrow-grass
Triglochin maritima
Tap image to enlarge · Wikimedia Commons
Overview
Sea Arrow-grass is not a true grass — it's a member of the arrow-grass family. It grows in dense stands on the saltmarsh at Marshside, its narrow, fleshy, cylindrical leaves looking superficially like rushes. The tall flower spikes produce small, inconspicuous green flowers followed by distinctive elongated fruits. It's one of the dominant plants of mid-saltmarsh. Important food for geese and wildfowl, which eat the leaves and seeds.
At a Glance
| Order | Alismatales |
| Family | Juncaginaceae |
| Habitat | Saltmarsh · Tidal creek edge · Coastal wet grassland |
| UK population | Common on all UK saltmarsh systems and coastal wet ground |
| Sefton Coast | Abundant in the Marshside and Crossens saltmarsh |
| Conservation | UK Green List |
Where to See It
Saltmarsh at Marshside RSPB and Crossens. Very common in the mid-saltmarsh zone.
Identification
Narrow, cylindrical, fleshy leaves arising in a basal rosette. Tall, unbranched flower spike with small green flowers. Elongated, three-parted fruits. Growing in saltmarsh. Superficially like a grass but leaves cylindrical.
Viewing & Photography Tips
Walk the Marshside saltmarsh — Sea Arrow-grass is common in the mid-zone. Look for the cylindrical, fleshy leaves and the tall flower spikes.
Conservation Status
UK Green List
This species has a favourable conservation status in the UK and remains an important part of Sefton Coast biodiversity.
Frequently Asked Questions
Is Sea Arrow-grass toxic?
Sea Arrow-grass contains cyanogenic glycosides that can release hydrogen cyanide if the plant is damaged. In normal conditions this is not a problem. However, when plants are wilted or drought-stressed, toxin concentrations can increase, and cases of livestock poisoning have been recorded. In UK conditions and at normal grazing pressures this is not usually a significant hazard.
Related Species
Plan your visit to the Sefton Coast
Marshside RSPB, Formby pinewoods, Ainsdale NNR — practical guides to getting there, what to bring, and the best spots for each season.