Spartina (cord grass)
|Botanical Name||Spartina spp.|
|Origin||Mostly N. and S. America|
IdentificationPerennial rhizomatous grass up to 1 m tall. Distinctive longitudinally wide ribbed, alternating leaves. There are two species and one hybrid in NZ. The hybrid (S. x townsendii) is rare and has never been found north of Kaipara Harbour. Of the other two S. alterniflora is the most robust (stems over 8 mm diameter) and forms more open clumps. The ligule (row of hairs where leaf meets stem) is 1-2 mm. It is the most common in Northland and hardly ever flowers. S. anglica is smaller (stems over 5 mm diameter), forms dense clumps and meadows and has ligules to 3 mm long. Spartina can be distinguished from tall fescue (Festuca arundinacea) by the deeply ribbed upper-leaf surface and from couch (Elymus spp.) by the short fleshy rhizomes.
HabitatsWetlands, especially estuaries.
Impact to Biota and EcosystemsVigorous grass which can form large meadows and occupy considerable areas of estuarine sand and mudflats. Traps sediment. Originally planted for reclamation purposes but this mostly proved unsuccessful. S. alterniflora is the greatest cause for concern in the North Island. Estuary habitat for other plants and also animals is almost completely lost with stands of spartina. Degrades natural character of estuaries. Can cause flooding by trapping backed up water.
Dispersal Routes, Vectors, Infestation SourcesPlanting and transplanting is a major cause of spartina invasion though this is prohibited now. Only S. anglica which is the less common species, spreads by seed. Both species spread by rhizomes and fragments and can break off and wash downstream.
|Physical Control||Small stands can be hand pulled or dug out but care must be taken to remove all rhizomes, dispose of carefully and follow-up. Although stock graze spartina, grazing is not recommended as rhizome fragments caused by trampling are transported downstream.|
(i) Gallant is very effective but a consent must be obtained when using herbicides over water in an esturaine area.
Rate - Gun and Hose 1 litre Gallant + 2 litres crop oil/100 litres water.
Control measures should be carefully planned and monitored and care needs to be taken to avoid associated damage to delicate estuarine systems.
This plant is prohibited from propagation, sale and distribution within the Bay of Plenty!