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.

Description

The leaf blades of young plants are dark green, hairless and flat, with an evenly ribbed upper surface and smooth, shiny lower surface. The youngest leaves are rolled in bud.

The mature plant is erect with shiny hairless leaves. Its hairless stems are often reddish-purple towards the base of the plant, particularly on younger plants.

Control

The prevalence of herbicide-resistant populations in many areas has made it more important than ever to take an integrated approach to managing annual ryegrass, involving non-chemical management practices as well as herbicides. With many post-emergent herbicides no longer effective against populations with developed resistance,

Sakura^® has become a key part of most growers’ management programs. See the Sakura Product Page for more information about all aspects of managing annual ryegrass.

Related Pests

Annual phalaris

Phalaris paradoxa

Annual phalaris is an aggressive annual grass weed that is generally a more serious problem in northern New South Wales and southern Queensland than in other cropping areas. It prefers alluvial, sandy-clay or clay texture soils with high soil moisture.

Capeweed

Arctotheca calendula

Capeweed is widespread throughout the southern cropping regions. Very little rain is needed to germinate capeweed seeds, so plants can emerge following ‘false breaks’ in early autumn and grow large before crops are sown.

Wireweed

Polygonum aviculare

The typical late germination of wireweed can make it hard to control. Although it may not compete strongly with the crop if it emerges when the crop is established, the long, tough branches of uncontrolled mature weeds can cause problems at harvest.