Vascular – Exotic
Aquatic: Emergent. Saline.
Stiff perennial grass 10-50cm tall, with fleshy rhizomes forming dense clumps or swards. Leaf blade 5-35cm x4-10mm, flat or inrolled, hairless and narrowed to fine hard tip. Culm erect, 3-8mm diam. near base incl. closely ensheathing leaves. Inflorescence 8-30cm, erect, seed always aborted.
Can be separated from S. alterniflora by the smaller culm (3-8 mm). and from S. anglica by its generally smaller size, (10-50 cm) and aborted pollen and seed (S. anglica is 50-100 cm tall and has viable seed).
Perennial. Does not set seed, reproduces entirely by rhizomes. S. xtownsendii is sterile and does not set seed. Dispersed by livestock, propellers, nets etc dislodge rhizome fragments, tidal and current movement, intentional planting. Can survive long-tem at sea, moves long distances.
Reason for introduction
Can tolerate extreme saline conditions.