Of increasing concern is the spread of Chilean needle grass (CNG) in the Braidwood area. Excellent spring & early summer rainfall has encouraged growth & seeding of this perennial grass weed in the area. So here are a few facts on this perennial, tussock forming grass:
* Introduced to Australia in the 1930s from South America;
* It can grow to a height of up to 1 – 1.5 m;
* Once it reaches flowering, livestock find it very unpalatable;
* Seed can remain viable in the soil for in excess of three years;
* Readily causes injury to livestock, as the panicle seed attaches to stock & burrows into the skin & eyes;
* Grows in winter & summer dominat rainfall areas, from 450 – 1000 mm annual rainfall;
* Best identified by seed: CNG forms three different types of seeds:
(i) panicle seeds: formed in summer with a characteristic purple colour,
(ii) stem seeds: form January-April along the leaf sheath;
(iii) basal seeds: found at the base of the plant. These seeds are formed very early in development & mature before flowering. No native grass species contain these three types of seed.
* The main distinguishing feature of CNG is the panicle seed, which has a characteristic purple colour, with a crown-like corona at the base of the seed. This corona is not found in native grasses.
Control options for CNG are similar to other perennial grasses, such as serrated tussock & African Lovegrass. Cultivation, chipping, grazing management or chemical control (using flupropanate +/- glyphosate) can be employed to control CNG. Cropping & establishment of competitive perennial grass/clover species is also essential for long term control of this perennial weed. Excellent control has been achieved by planting a sequence of fodder crops of 2-3 years to reduce the seed bank before establishing perennial pasture. Even the strategic use of fire can reduce the dominance of CNG in a mixed pasture.
To facilitate discussion on this significant weed, Landmark Daniel Walker is arranging a field day on Chilean needle grass early in the New Year, so keep an eye out for further details. In the meantime, for further information, please do not hesitate to contact our consulting agronomist, Roger Garnsey through Landmark Daniel Walker on 02 48 422405. Acknowledgements: Chilean Needle Grass National Best Practice Management Manuel, DPI Vic.