Being familiar with the worms on your property allows you to plan effective non-chemical management strategies and choose appropriate drenches. You get to know how they survive and what you can do to make survival difficult for worms.

The species of worms that are encountered vary from district to district and state to state. Weather conditions, the type of pasture, the effectiveness of non-chemical worm management strategies and your ability to diagnose and treat infestations in the past influence the activity of the different worm species on your property.

In general, you should focus on managing the truly important worms.  The others tend to be controlled along with the important ones.

The important worms in winter rainfall areas of Australia are

• Brown stomach worm (Ostertagia)
• Black scour worms (Trichostrongylus spp)
• Plus or minus liver fluke and barber's pole worm

In summer rainfall areas

• Barber's pole worm (Haemonchus contortus)
• Black scour worms (Trichostrongylus spp)
• Plus or minus liver fluke, nodule worm and maybe brown stomach worm.