Alternative common names:
Beach grass, Marram grass, European beach grass, European beachgrass, European marram grass, Sea reed
Marram grass is a grass with large resembling membrane structure (i.e. ligule), 10-30 mm long, where the leaf sheaths meet the leaf blades. Its seed-heads are relatively large (7-30 cm long) and its flower spikelets only have a single tiny flower (i.e. floret). These flowerspikelets do not have any obvious awns.It has been extensively planted as a sand binder on coastal sand dunes, but has spread from these plantings and is replacing native sand dune species.
Where does this species come from?Europe and North Africa
What is its invasive status in South Africa?NEMBA 2020 Category 3
Where in South Africa is it a problem?South African Coastline - Particularly Western Cape and Eastern Cape.
How does it spread?Spread by an extensive network of creeping underground stems (i.e. rhizomes). The underground stems produce seed, but these are often sterile. The seeds may be spread by wind, water and animals. Segments of its underground stems (i.e. rhizomes) and seeds may also be dispersed in contaminated sand.
Why is it a problem?
The grass is invasive in the introduced local ecosystems, forming dense monotypic stands that crowd out native vegetation, reduce species diversity of indigenous arthropods. The Marram grass interferes with the natural dynamics of dune ecosystems.
What does it look like?
Leaves: The leaves consist of a leaf sheath the encloses the stem and a rigid and spreading leaf blade. Most of the leaves are arranged towards the base of the stems with their sheaths overlapping. The very elongated (i.e. linear) leaf blades are greyish-green in colour and come to a sharp point at the tip (i.e. acute apex). These leaf blades (20-70 cm long and 1-2.5 mm wide) are usually tightly inrolled (i.e. involute), but may be up to 6 mm wide when flattened. Their upper surfaces are hairy (i.e. pubescent), while their undersides and hairless (i.e. glabrous). Where the leaf sheathmeets the leaf blade there is a relatively large elongated membranous structure (i.e. ligule) 10-30 mm long, which is often partially split in two
Flowers: The spike-like seed-heads (i.e. inflorescences) are borne at the tips of the stems and consist of several branches that are held closely to the stem (i.e. they are spiciform panicles). These seed-heads (7-30 cm long and 1-3 cm wide) are relatively long and narrow (i.e. narrowly-oblong tolanceolate-oblong) and contain numerous densely arranged flower spikelets (10-18 mm long). The individual flower spikelets are elongated in shape (i.e. narrowly-oblong) and brone on stalks (i.e. pedicels) 1-4 mm long. They consist of a pair of bracts (i.e. glumes) and a single tiny flower (i.e. floret). The floret has two floral bracts (i.e. a lemma and palea), three stamens (4-7 mm long) and an ovary topped with a feathery two-branched stigma. Flowering occurs mainly during spring and early summer (i.e. from October to February).
Fruit/seeds: The seed-heads turn from green to straw-coloured or pale brown as they mature. The flower spikelets break apart at maturity, with the bracts(i.e. glumes) remaining on the seed-head and the floret being dispersed. The 'seeds resemble the shape on an egg.
Does the plant have any uses?
The plant was used to stabilise and establish sand dunes for forestry plantings, property protection and erosion control.