Arundo donax

giant reed

 

Arundo donax

L. 1753

pronounced: uh-RUN-doh DON-aks

(Poaceae — the grass family)

 

common names: giant reed, giant cane

Arundo (harundo), is Latin for a tall reed, while donax is of Greek origin, δοναξ, ‘a reed shaken by the wind’, referring to its seed-dispersal. This plant is of Mediterranean origin. Ancient Egyptians wrapped their dead in its leaves. Since then it has been introduced into many parts of the world, temperate regions as well as tropical. It has been cultivated throughout Asia, southern Europe, northern Africa and the Middle East for thousands of years. It was introduced into Australia as an ornamental, and has now become an environmental weed in some parts of the country. The clump photographed is near the old helipad in Nelly Bay.

As far as I can ascertain, Arundo donax is the only species of the genus found in Australia. The genus consists of tall perennials with thick, knotty rhizomes, and, when fully grown in suitable conditions, they are almost as large as Golden Bamboo.

Our species generally grows to about 6 m, but it can exceed 10 m in height, with stems 2 – 3 cm in diameter. The leaves are alternate, 30 – 60 cm long and 2 – 6 cm broad with a tapered tip, grey-green, and have a hairy tuft at the base.

It flowers in late summer, bearing upright feathery plumes 40 – 60 cm long, but the seeds are rarely fertile. Instead, it reproduces vegetatively, by underground rhizomes. These are tough and fibrous, forming knotty spreading mats that penetrate deep into the soil, down to about 1 m. Stem and rhizome pieces as little as 5 cm long and containing a single node are able to sprout under a variety of conditions. This vegetative growth appears to be well adapted to floods, which may break up individual clumps, spreading the pieces, which may then sprout and colonize further downstream. It uses large amounts of water when it is growing in a wet habitat, to supply its rapid rate of growth, up to 5 cm a day in spring. It is capable of growing in dense stands, which may crowd out other plants and prevent their growth. The canes contain silica, perhaps the reason for their durability, and they have been used to make fishing rods, walking sticks and paper.

The stem material is both strong and flexible. It is the principal source material for reeds of woodwind musical instruments (oboe, clarinet, bassoon and saxophone) and is also often used for the chanter and drone reeds of many types of bagpipes. It has also been used to make flutes for over 5,000 years, particularly pan pipes. Its stems are also used as garden canes to provide support for climbing plants and vines.

It was introduced from the Mediterranean to California in the 1820s for roofing material and for erosion control in drainage canals in the Los Angeles area. Through spread, and subsequent plantings as an ornamental, and for use in making reeds for woodwind instruments, it has become naturalized throughout the warm coastal freshwaters of North America. It has been planted widely through South America, as well as Australia and New Zealand, and I have seen it growing in the UK around ponds in gardens and parklands.

This is one of the fastest growing terrestrial plants.

 
Photographs taken 2009-2013, Nelly Bay
Page last updated 13th October 2018