Weeds are estimated to cost Australian agriculture more than $2.5 billion per year. Understanding weeds and the various methods to control them ultimately reduces costs and improves productivity.
The Department of Primary Industries and Regional Development conducts research into the management of weeds and has developed integrated weed management (IWM) packages, that incorporate a number of varied weed control options, including chemical, physical and biological strategies, are vital for sustainable weed management in this state.
Weed populations that have developed herbicide resistance, where standard herbicide treatments are no longer effective, pose an increasing threat to WA’s agricultural production.
Farmers are often concerned that weeds may reduce crop yields. Weeds use the same nutrients that crop plants use, often in very similar proportions. They also use resources such as water, sunshine and space that might have gone to crops. The more similar the weed and crop requirements, the more they will compete for those resources. Weeds that compete aggressively with crops reduce their yield. Weeds are most damaging to crop yields if they have some advantage over the crop. Four factors are especially important: density, timing, size and chemistry.
Funding provided by the Canada-Saskatchewan Agri-Food Innovation Fund
Weeds can cause problems other than crop yield loss. Some weeds are poisonous and can taint food and feed crops. For example, wild mustard seed cannot readily be removed from canola, and can flavor the resulting canola oil if crushed with the crop seed. Stinkweed in feed for dairy cattle produces off-flavors in milk.