The Planted Native Flowering Grassland

by John Delpratt

The remnant native flowering grassland communities of southern Australia provide a tantalising and poignant glimpse of a pre-European landscape. Now restricted to flora, railway and road reserves, isolated cemeteries and lightly grazed paddocks, they once clothed vast treeless plains and enriched the understorey of open woodlands. In recent years, considerable effort has been directed towards a better understanding of these fragile and threatened communities of plants and animals. While we have sparse knowledge of the exact composition of these near-extinct plant communities, a relatively intact temperate grassland will consist of three broad groups of native plants.

1. Cool season grasses
   These perennial grasses grow actively during spring and autumn and may stay green during summer if soil water is not limiting. Common species include the wallaby grasses (Danthonia spp.), tussock grasses (Poa spp.), spear grasses (Stipa spp.) and Weeping Grass (Microlaena stipoides).
2. Warm season grasses
   Warm season perennial grasses are in active growth during late spring and summer. An example is the widespread and statuesque Kangaroo Grass (Themeda triandra), a dominant component of many Australian grasslands. Other species which grow actively over summer and are dormant during winter include Windmill Grass (Chloris truncata) and Red-leg Grass (Bothriochloa macra).
3. Seasonal wildflowers (forbs)
   The so-called flowering component of grasslands and grassy understoreys includes a numerous and diverse group of herbaceous, perennial plants other than grasses (forbs), which flower sequentially from early spring through into autumn. Spring is announced by the first appearances of the delicate lily, Early Nancy (Wurmbea dioica), to be followed closely by various terrestrial orchids, Bulbine Lily (Bulbine bulbosa), Milkmaids (Burchardia umbellata), Chocolate Lily (Arthropodium strictum) and Creamy Candles (Stackhousia monogyna). As the season develops, the grasslands glow with Common Everlastings (Chrysocephalum apiculatum), Spur Velleia (Velleia paradoxa) and Scaly Buttons (Leptorhynchos squamatus). Moister areas explode with massed stands of Billy-buttons (Craspedia variabilis -see right) and Australian Buttercups (Ranunculus lappaceus). Late spring and summer introduce the elegant blues of Australian Bluebell (Wahlenbergia stricta -see top left) and Blue Pincushion (Brunonia australis), the metallic blues and mauves of Blue Devil (Eryngium ovinum) and the extraordinary straw coloured inflorescences of Feather-heads (Ptilotus macrocephalus). By early autumn, the Kangaroo Grass is turning bronze, highlighting the erect silver stems and brilliant lemon flowers of Lemon Beauty-heads (Calocephalus citreus). In the woodland understorey, the bright yellow heads of Wiry Buttons (Leptorhynchos tenuifolius) contrast with the drying seedheads of the grasses and forbs that have gone before.

A flowering grassland is a diverse, complex and dynamic system. The cohabitation between plant groups depends on intermittent disturbance, such as grazing and fire, to reduce the vigour and cover of the grasses. Disturbance creates gaps between the grass tussocks where the colourful, seasonal forbs can establish and thrive. For many years, botanists, ecologists, plant scientists and naturalists have been advocating the retention and protection of remnants of these precious and exciting reminders of past floras. Many have promoted and researched the use of their component species to develop attractive, low maintenance and water efficient landscape styles for roadsides, public open space and private plantings. With our present knowledge, it is not realistic to expect to recreate a fully functioning flowering grassland within a reasonable time frame. We can aspire to establish attractive and functional plantings that share many of the desirable attributes of natural grasslands.

Research and experience in Australia and in other parts of the world show that there are some common issues faced by those attempting to reconstruct flowering grasslands. With the generous support of the Potter Foundation, we at Burnley College are building a planted grassland. Our research will help us better to understand how to cultivate and manage these little known wild species for habitat reconstruction and a range of landscape applications.
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About the writer: John Delpratt lectures in plant production and seed technology. His research interests include the cultivation of wildflowers for seed production and the construction of planted flowering grasslands.

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