By Anne Batt
Most people are aware of the problems of rice grass in the Tamar Estuary itself, but along the coastal beaches on both sides of the Tamar and further along the northern coastline, marram grass is posing a different threat. Both were initially planted to solve one problem, but are now causing different problems.
From early childhood, marram grass and sandhills were an essential part of our experience of the beach. For us that tough, spikey grass has always been there.
Marram grass is not a native grass, but was introduced to deal with a particular problem arising from European colonisation.
What was the problem? Australia has a lot of coast, a lot of sand and a lot of wind. Coastal areas around the mouths of rivers were the most attractive areas for early settlement. The settlers brought animals, agricultural practices, permanent buildings and the idea of fixed property boundaries with them to Australia. The coastal dunes were probably always fairly mobile, but grazing and foraging animals, and the harvesting of wood rapidly denuded the dunes of their natural vegetation releasing the sand.
Newspapers reported the problem of sand invasions in New South Wales in the 1850s. The inner-city Sydney suburb of Strawberry Hill was a huge sound mound. The settlers and their animals removed the vegetation and the sand was set loose. Houses, gardens, fences and wells were all buried, and the sand threatened to fill Darling Harbour. The sand dunes at Newcastle also threatened roads and port facilities.
Although the shifting sands had become an increasing nuisance, it was the introduction of rabbits to Victoria in 1859 that exacerbated the problem. Coastal settlements on Victoria’s west coast were severely affected. The Argus noted the rabbit problem in 1886:
“What was needed was a determined effort to stop the growth of the nuisance. The way in which the rabbits were burrowing under the sand-hills on the seashore at Belfast (Port Fairy) would so loosen the soil that, unless they were extirpated then, the adjoining country would become covered with sand dunes.”
The residents of Port Fairy sought advice from Baron Ferdinand von Mueller, the Government Botanist for Victoria. He recommended that the council plant their dunes with marram grass. Marram is native to the sand-dunes of western Europe and had been deliberately propagated and planted on dunes with the first such use recorded in the Netherlands in 1423.
Towards the end of 1885, Von Mueller imported a sample of marram grass for the Port Fairy borough. 1886 saw the borough ranger, Mr Avery, planting out marram on the dunes. The grass thrived in the mobile coastal dunes, and was observed to be almost indestructible. Avery was soon propagating the grass to share with neighbouring settlements, as well as sending consignments to the other colonies.
Northern Tasmanians through their Bass Strait ports were in regular and frequent contact with the settlers in Victoria. The news of the successful stabilisation of the dunes with marram at Port Fairy was soon being reported in Tasmanian newspapers. The first plantings in Tasmania were in 1893-94.
After battling encroaching sand on their farmland, roads and the Emu Bay Railway line, the Van Diemen’s Land Company took the lead, planting the 1,000 acres on the dunes of their extensive land grants. In October 1894, the Company demonstrated the efficacy of their plantings at West Beach, Stanley to government ministers visiting the area. The Lands Department, Marine Boards, Road Trusts and local councils soon became involved in planting the dunes. The VDL Co. became the main supplier in the state.
Encroaching dunes were a major problem on the North-East Coast between Little Piper River and Bridport. In 1908 the Lands Department arranged the planting of the dunes, with local residents having the job of protecting the grass until it became established. The grass was planted at Marrawah in 1910 and Waterhouse in 1911. In 1921, the George Town Council procured 5 bags of marram grass roots from the VDL Co. and the task of planting the grass was assigned to the Dalrymple Ward members.
In the post-war era, dune encroachment continued to be a problem for coastal farmland opened up for soldier settlement. In 1955 the Lands Department set up the Sand Dune Reclamation Unit to halt the invasion of the dunes at Waterhouse. This Unit was still operating in 1995. The Public Works Department was also engaged in planting marram from 1902 through to the 1940s.
About a century after the introduction of marram to Australia, scientists and coastal engineers expressed concern about some adverse effects. The grass is extremely robust, invasive and hard to control. It thus disrupts natural coastal vegetation. The natural shape of dunes is an incline down to beach level. Storm waves would normally lose erosional power running up the sloping face of the dunes. But Marram holds the sand in such a way that sand is scoured from the face of the dune by storm waves leaving a steep slope, and eroded sand deposited in off-shore bars.
This is becoming a particular concern with the prospect of a rising sea level and the increasing intensity of storms associated with global warming. We are only part way through the marram grass saga!