Wild oats

Avena fatua

Wild oats have evolved in parallel to winter cereal crops and are particularly well suited to compete strongly with wheat. Left uncontrolled, they can reduce wheat yield by as much as 80 %.

Description

Wild oat seedlings have leaves twisted anticlockwise – the opposite direction to wheat and barley.

The sheaths are smooth or slightly hairy, especially in younger plants. The dark green leaf blades remain twisted and the youngest leaf is rolled. Mature plants reach up to 150 cm.

Control

Wild oats are probably second only to annual ryegrass as the most challenging grass weed in winter cropping. Resistance to herbicides with older modes of action is widespread, so integrated weed management is essential.

As with most of the key grass weeds of winter cropping, Sakura provides effective early and lasting control in favourable conditions with no cross-resistance.

Related Weeds

Brome grass

Bromus diandrus

Brome grass and wild oats have been rated the two most competitive grass weeds in wheat. Western Australian research has shown that brome grass at a density of 100 plants/m2 can reduce wheat yields by 30%.

Barley grass

Hordeum leporinum

Although not a major winter cropping weed in all areas, barley grass is prevalent in some areas with higher winter rainfall. A combination of its potential for rapid germination and developed resistance to Group A and B herbicides can make barley grass difficult to control.

Annual ryegrass

Lolium rigidum

Annual ryegrass (Wimmera ryegrass) is arguably the most important grass weed competing with winter cereal crops in Australia. The rapid spread of herbicide-resistant populations in recent years has even threatened the viability of cropping in some areas.

Silver grass

Vulpia bromoides; Vulpia myuros

Even though silver grass is less competitive than other major grass weeds, dense populations can severely limit crop yield. Another weed that has become more of a problem since the adoption of minimum tillage practices, it is most likely to emerge in high numbers in crops sown early by direct drilling.