There are a number of products available for control of Wild Oats in cereals, all of which will produce a satisfactory result given the right conditions. However, there are very significant cost differences and certain situations where one product would be a better option over another.

Considerations in product selection include:

· Efficacy. The performance of products registered to control Wild Oats can vary with climatic conditions and growth stage of the weed. Group B products work best when soil conditions are moist and weeds are small. Products such as Mataven will only work in warm temperatures. Understanding the limitations of the various products is important to ensure sufficient efficacy is achieved to obtain control.

· Resistance Status. Resistance to Group A (fop) herbicides in Wild Oats is common. Resistance to Group A (dims) and Group Bs is less common, however increasing rapidly. Understanding the resistance status of the Wild Oat population to be controlled is vital to product selection. Rotation of chemical groups is a critical management technique to maintain the efficacy of post-emergent herbicides.

· Other Weeds Present. Most products are registered on a number of other grass weeds and in some cases broadleaf weeds as well.

· Cost. Prices range from $7/ha to $40/ha. Therefore cost should be a major consideration in product selection after taking the above into account.

· Growth Stage. Grass weed control should be carried out at the earliest opportunity when weeds are small and more susceptible to herbicides. Early removal reduces crop competition and improves the economic result.

· Grazing Withholding Period (WHP). Should grazing wheat require a grass weed spray, the WHP becomes a critical factor in product selection. Achieve has a 2 week WHP, Wildcat and Foxtrot have a 3 week WHP, while Topik has a 4 week WHP.

· Plant Back Period. Generally this is not a consideration, however with the increasing number of Group B products available, the plant back restrictions to pulses, legumes and pastures needs to be considered.

Following are some specific comments on the more common products available.

Achieve Good Wild Oat control, weak on Annual Ryegrass.

Atlantis Most effective on small weeds. Good Wild Oat control. Also effective on Annual Phalaris. Less effective under dry conditions.

Axial Most compatible with broadleaf weed control products.

Hussar Good Wild Oat control. Also effective on small Annual Ryegrass and broadleaf weeds. Less effective under dry conditions.

Crusader Similar to Hussar. Suppression of Annual Ryegrass only.

Mataven Good control of Group A & B resistant Wild Oat populations. Very expensive. Requires warm conditions. Selective spray topping option to reduce Wild Oat seed set.

Topik Generally most cost effective option for control of “fop” susceptible Wild Oats.

Wildcat Strong on mixed populations of “fop” susceptible Wild Oats and Annual Phalaris.

The following table outlines some of the key features of each product which require consideration prior to application.

Based on the above information, Topik is likely to be the product of choice where Wild Oats are Group A (fop) susceptible. For Group A (fop) resistant populations, Achieve Group A (dim), Axial Group A (den), or a Group B product may provide control. Group B products whilst expensive, have a place where rotation of chemical groups is required, or broadleaf weeds are present and can be controlled with one pass. Alternatively, Mataven can be used at the full rate early, or at the lower spray topping rate later.

Post-Emergent Wild Oat Control in Cereals