Fairy grass Fact Sheet 1
Fairy Grass – A Coloniser Plant
Fairy Grass or Common Blown–grass (Lachnagrostis filiformis) is an emerging native plant in Australia which has colonized extensive areas of dry lake beds in western Victoria during the current changed climatic conditions. Large numbers of the plants’ detached seed heads lodge against fences, railway lines, machinery and buildings. This accumulation of material initiates concerns with respect to the safety, fire hazard, and the general nuisance it provokes.
The grass is an annual, meaning it germinates from seed, produces seed in the same growing season, then perishes after seed production, having distributed huge number of seeds ready for the following season. However, the plant can survive up to three years where sufficient moisture exists.
Fairy Grass tends to germinate, as soon as moisture conditions and temperature are suitable, generally emerging in June to August and producing seed heads between November and February.
Fairy Grass tends to establish its presence from seed blown in from significant distances away and germinates in exposed soil. In the second year of a lake bed being dry it rapidly spreads across bare surfaces. It is referred to as a pioneering species that quickly invades bare soil and as the soil is stabilised is replaced by other species that can compete through earlier germination, longer life cycles (perennials) or taller habit.
Research Recently Completed
University of Ballarat research reveals Fairy Grass causes seed headed related problems in at least 17 lakes and swamps across Western Victoria and has the potential to rapidly spread extensively across southern Australia.
Current control measures for Fairy Grass include herbicide treatment, burning, and slashing. These are costly, but do provide short term relief from problems associated with wind blown seed heads. Until recently, little was known about their long term effects, as significant rainfall resolved the problem.
Fairy Grass has extensively covered Lake Learmonth since 2002 and developed significant populations in Lake Burrumbeet and Lake Wendouree over the last summer season which impacted heavily on surrounding properties.
Research has been undertaken on lakes Learmonth and Polpara and at McCosslens Swamp over two successive growing seasons.
Herbicide treatment, burning and slashing at these sites reduced the volume of seed heads dispersed from the lakes. It also resulted, with successive application, to increase the density of Fairy Grass in consequent growing seasons.
This is attributed to the removal of desirable competition, which created a suitable germination environment for Fairy Grass the following year.
Research findings suggest that longer term effective management strategies must be found if lakes are likely to regularly become dry. Further, if conditions remain, rare and threatened species may be threatened by current control practices.