Online tool tackles worst of NZ pasture pests and weeds

The AgPest website is a feature of the AgResearch display in the Mystery Creek Pavilion at this year’s National Agricultural Fieldays.

The AgPest (formerly known as Pestweb) display highlights some of New Zealand’s worst pasture pests, and demonstrates the online tool as a practical way for farmers to identify and then tackle the problem.

Scientist Colin Ferguson says the aim of the AgPest display is to ensure continued and productive pasture growth, and it fits with the theme of the AgResearch stand, which is featuring science which farmers can use to increase their knowledge on farm.

“We’re highlighting pests such as porina and black beetle; both are causing damage to New Zealand pastures currently as the mild winters and warm springs over the past few years have produced the perfect conditions for adult black beetle and porina survival.”

Porina are grazers that will eat all herbage that is on surface of the ground. The amount of damage depends on the number of insects; at low densities they are direct competitors with stock for food and reduce the amount of foliage available. At higher densities plants are destroyed allowing inferior plant species to establish reducing long term pasture quality and production.

“Paddocks that are two to three years out of cultivation are particularly prone to porina infestation,” says Mr Ferguson.

Black beetle numbers are also high where populations are found in the upper North Island.

“Black beetle adults usually go into a rest period over winter, becoming more active again when it warms up in spring,” says Mr Ferguson.

“Awareness will help farmers plan for combat strategies to make up for the feed consumed by this pest. These may include putting in a maize silage block or buying in additional feed if appropriate.

“You can find out more about the control of both porina and black beetle at the AgPest website.”

Built for farmers and agricultural professionals, the recently renamed website ( is a free online tool to assist with pest and weed management decision making.

“Visitors can find over 80 pests and weeds that affect New Zealand pasture in the pest directory. Each pest profile includes the biology of the pest, its impact on pastures and the latest information on control measures,” says AgResearch weed scientist Dr Katherine Tozer.

“One of the site’s key features is the ability to help farmers identify a particular weed or insect pest they find on the farm through a simple query and response system.

“While we were rebranding the site we also took the opportunity to include a new site-wide search function.

“AgPest Alerts is a free subscription email service providing timely alerts to farmers about pest outbreaks in their region. They are delivered via email, text, Twitter or Facebook and link to the AgPest site for further information. You can sign-up for the service on the AgPest site,” says Dr Tozer.

For further information please contact: 

Alex Fear
Senior Communications Advisor
AgResearch Limited
T   07 834 6636
M 021 773 674

Comments are closed.