What was it all about?

This project investigated the effects of different landscapes that surround fields on pest management in vegetable and other crops. Overseas research has found a protective effect of maintaining semi-natural habitats around crop fields, as this supports populations of beneficial arthropod species.

The project team made a critical overview of relevant research in Australia to see if the same effect might be found here. They also consulted with 26 expert researchers.

Key findings included…

• Native plant species tend to support beneficial insects that prey on pest insects, whereas weeds tend to support pests
  
  
• Beyond individual native species, native vegetation also increases the numbers of beneficials by providing shelter and resources, and there is evidence to show that they move from native vegetation to the crop
  
  
• Benefits of native vegetation varies with:

o The quantity, type and configuration of native vegetation (for example, individual paddock trees, retained strips or blocks)

o The condition of native vegetation

o The complexity of the habitat such as whether it has under, mid and overstory layers

• Lucerne in surrounding areas was found to promote the numbers of beneficials, as well as providing additional farm income.

The researchers noted that there is still much to be learned about the effects of surrounding landscapes for crop production, but made the following recommendations for growers…

• Maintain native vegetation on farm, particularly woody vegetation at field margins 
• Remove weeds from semi-natural areas 
• Combine this with integrated pest management of crops, particularly reduced pesticide application
• Consider regionally suitable species of perennial native plants that could also provide additional farm income, such as plants for the native cut flower industry, native bush tucker and seed for the native revegetation industry 
• Improve habitat quality by maintaining layers of vegetation and avoid overgrazing.