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.
Photo: A.D. Warnock – University of Ballarat.
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.