Supporting culturally significant native plants with environmental water
Author: Dr Will Higgisson
For more than 60,000 years, over 40 Aboriginal nations have been caring for the Country that the Murray-Darling Basin is within. While diverse, Aboriginal peoples share cultural connection and custodial responsibility for water, which for thousands of generations has held meaning and purpose, detailed through lore and customs. As well as these customary values, the rivers and wetlands have been cared for by Aboriginal people and provided productive areas rich in resources in an often-dry landscape. Through this relationship with Country, the complex connectedness of land, water, plants, and animals is deeply embedded in Aboriginal knowledge systems.
The Murray-Darling Basin is home to a large number of native plants across many diverse ecosystems and sites. Many of these sites along rivers, floodplains and wetlands can be associated with particular uses for the collection and cultivation of plants for food and medicine and for the production and manufacture of tools. For these sites to be productive, they were known to rely on certain hydrological conditions. Large scale changes in water management practices ill-suited to a climate of multiyear drought cycles after colonisation and the removal of Aboriginal peoples from Country led to widespread changes in the landscape and ecosystems.
Through the Flow-MER program, Ecologists at the Centre for Applied Water Science are working with the Commonwealth Environmental Water Holder to improve our understanding of how environmental water can help to maintain important sites and values across the Murray-Darling Basin. Using vegetation data collected across the selected areas in the Basin between 2014 and 2020 we described the response to flooding and drying of three widely used plants including a food plant (Nardoo), medicinal plant (Old Man Weed) and a plant used for fibre (Cumbungi).
Nardoo
Nardoo (Marsilea spp.) forms large fields of cover across floodplain regions in response to flooding, producing a nut-like object up to 9 mm long called a sporocarp; a hard capsule in which there are spores packed in a starch-like substance. The sporocarps are roasted, ground, and then mixed to make a dough. The dough is then baked, producing bread or seedcakes high in protein and carbohydrates. This process and production was once on such a large scale across the Murray-Darling Basin that sets of grinding stones known as ‘Nardoo Mills’ are commonly found in regions long distances from where the stone originated. Nardoo features in the story of Burke and Wills ‘Life saver or life taker.’
Old Man Weed
Centipeda spp. known as Babiin (pronounced Ba Been) or Budhaanybudhaany in Wiradjuri. Babiin loosely translates to father or old man; hence it is known as Old Man Weed. Old Man Weed is commonly found throughout the South-East Murray-Darling Basin, and grows in moist soils near rivers, wetlands and billabongs. It is a perennial plant that produces flowers from September to February.
Old Man Weed is known as a cure-all and is an important medicinal plant to many Aboriginal nations in the Murray-Darling Basin. The leaves are boiled and used for colds, coughs, and to wash sores. It can be crushed in the hand and sniffed to relieve cold symptoms. Tea made from the plant is drunk as a health tonic and for upset stomachs. It is also used to treat arthritis and tuberculosis.
Cumbungi
Cumbungi (Typha spp.) occurs in wetlands that have permanent or near-permanent water regimes and hydrologically stable conditions. It has been described as one of the most valued aquatic plants in the Murrumbidgee Catchment, and is used across other parts of the Basin.
It is a plant with many uses. It is an important fibre plant used to weave baskets and rope and can also be woven into nets used for hunting animals. The seed heads are used in ceremonial decorations and the rhizomes (the roots or stems) can be cooked and eaten, providing an important source of starch. And if you are after a salad, the young shoots can be eaten raw.
Key Learnings
Environmental water has supported a range of native plant species in the Murray-Darling Basin. Our research has shown that Nardoo, Old Man Weed and Cumbungi are more abundant at sites that have been recently flooded and this reduces with time since flooding. During dry years these plants reduce in abundance and cover and often only occur in lower lying parts of the floodplain which are flooded more frequently. Following re-wetting, they establish and grow rapidly. These flooding events provide the conditions required for growth, reproduction and establishment.
Through engaging with Aboriginal communities across the Basin we can learn values such as important locations, species or practices which can be supported with environmental water. This can help establish more specific cultural objectives for vegetation outcomes in the Basin and help inform the design of watering actions and contribute to supporting plant species diversity across the Basin.
Feature image: Environmental water in the redgum woodlands of the Great Cumbung Swamp, Lachlan River, June 2020. Credit: Fiona Dyer
Why Vegetation?
The Vegetation Theme evaluates the contribution of Commonwealth environmental water to the diversity and condition of non-woody vegetation across the Murray- Darling Basin, as well investigating how to best use it to achieve environmental outcomes for tree species such as River red gum and Black box.
