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A planted weed
Ammophila arenaria - Marram Grass - is a coarse, spreading
grass of coastal sands which grows to about a metre tall. It is
found all along the Victorian coastline except in areas where there are
limestone cliffs or salt-marshes. Marram Grass is native to
western Europe and was first introduced into Victoria, from England, in
the 1880s as a means of stabilising sand dunes which had become severely
eroded due to heavy clearing of coastal vegetation by European settlers.
This practice was continued for the next 100 years through the devices
of various government agencies, chief amongst which was the, now
defunct, Soil Conservation Authority. Today, Marram Grass is
considered to be an environmental weed and the Victorian Government does
not use or recommend it for coastal revegetation programs. In
addition, there are many local programs where efforts are being made to
remove it from native vegetation and to encourage local species in its
place.
Marram Grass is not entirely without its virtues in coastal
vegetation. It is probable that in many areas where it had been
introduced, all of the native vegetation had been removed and only bare,
eroding sand remained. The Marram Grass stabilised and built up
the dunes in areas immediately adjacent to the sea, a process that often
allowed native species, particularly shrubs and herbs, to re-establish.
The result has been a semi-natural vegetation (other non-native species
are also regular components) along much of the Victorian coast and while
this is not the most desirable outcome from a conservation standpoint,
it is arguable that that things may have been much worse without its
introduction.
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One of the problems with Marram Grass is that the kind of dunes it
creates are normally much steeper than than those that would have
otherwise developed, with the consequence that some native flora and
fauna (e.g. Little Penguins) find it difficult to survive in this
environment. Another is that it comes to dominate the landscape to
such a degree that native grasses and sedges cannot compete.
Ferdinand von Mueller, Victoria's first Government Botanist, was the
person who recommended that Marram Grass be employed as a sand-binder
when the erosion problems were presented to him. He was familiar
with the species in Europe where it was often used for the same purpose.
Von Mueller apparently didn't consider using the the native sand-binding
grass, Spinifex sericeus (Hairy Spinifex) possibly because
little was known about its propagation and there was no seed store of
the species available at the time. Marram Grass seed, on the other
hand, was readily available from England (even though it took some
months to import it) and techniques for establishment were well known.
In addition to these practicalities, von Mueller was one of a group of
19th century European biologists who thought that it was
their responsibility to introduce useful species of animals and plants
to colonial settlements around the world.
This concept was known as acclimatisation and
von Mueller, along with Frederick McCoy, the director of the Melbourne
Museum, was one of the founders of the Acclimatisation Society
of Victoria. The problem with those involved with
this process was that the determination of what was a useful or
desirable species was an arbitrary one, often dictated by the personal
bias or self-interest of individuals. As all of the Society's
members were Europeans there was an inclination to assume that species
from that part of the world were superior to those from the colonies.
Thus the introduction of trout to rivers, deer and rabbits to
grasslands, songbirds and deciduous trees to urban gardens and
blackberries to bushland gullies, were all meant as improvements to the
natural environment.
© Paul Gullan, Viridans Biological Databases
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