Weed Alert – Serrated Tussock (Nassella trichotoma)

WHAT IT LOOKS LIKE: Serrated tussock is a perennial tussock grass growing to 50cm high with erect bright green (“bleached blonde” in winter) rolled leaves less than 1mm wide. Long, branched flowering stems are slender and weak, often weep over, and trail on the ground, rather than erect like some native grasses. The flowers are enclosed in a red sheath, and combined with the weeping habit, give the flowering plant a pink cushion-like appearance. The seed is tiny and almost round, with a fine thread-like awn attached off-centre at one end.

HOW IT SPREADS: Spread is mostly by wind, although seed can be transported in and on animals, clothing, vehicles, and machinery. The entire seed head snaps off when seed is ripe, and blows around. Large accumulations pile up along fences and catch on other vegetation such as shrubs and thistles. The native Hairy Panic (Panicum effusum) also does this, but its stems are thicker and straighter

WHY IT’S A PROBLEM: The huge financial cost to agriculture of weeds and weed control is well known and the devastating impact of weeds on natural vegetation is widely recognised. Weed invasion is one of the greatest threats to many communities of native plants. Weeds can come to dominate the landscape, significantly reducing agricultural productivity and preventing regeneration of native plants or even killing them in some cases. Weeds result in reduced habitat for native animals and change the visual character of the landscape.

WHAT YOU CAN DO: Learn to recognise weeds and take early action to control them on your property:

• Have unfamiliar plants identified if you think they may be weeds. • Avoid unnecessary soil disturbance. • Monitor areas where you have imported materials or created disturbance, and be ready to control weeds as soon as they appear. • Avoid overgrazing as this creates ideal conditions for weed invasion. • Insist that contractors’ clean machinery before bringing it onto your property and monitor areas where such machinery has worked for new weed arrivals. • When feeding stock on imported hay or grain, do it in a restricted area and monitor afterwards for weeds. • Quarantine new livestock for up to two weeks so weed seeds can pass through them in a confined area which can be treated later. • Find out about the weeds present on properties you buy feed or stock from and where possible avoid situations with significant weed problems. Request a commodity vendor declaration (CVD). A CVD is good for helping to manage on-farm biosecurity risks such as introducing pests and weeds from purchased fodder. • Don’t shift stock straight from weedy areas into clean paddocks or areas of remnant native vegetation, especially when weeds are seeding. • Get to know when weeds on your place flower and time your control efforts to prevent seed set. • Be vigilant, and act early. Do not wait until a few plants turn into a major infestation.

We will be talking more about effective methods for controlling serrated tussock and other grassy weeds next week.

For information, advice and assistance: •Visit Council’s website https://www.snowymonaro.nsw.gov.au/140/Biosecurity-and-Weeds •Download the free NSW WeedWise app https://www.dpi.nsw.gov.au/biosecurity/weeds/nsw-weedwise-app •Call Council’s Biosecurity Officers 1300 345 345