Lawn Alert - Are You Seeing Brown Patches in Your Lawn?

How to Control Porina Caterpillar and Grass Grubs

During late winter, spring & early summer, porina caterpillars are a destructive lawn pest in much of the country. Porina are the larvae of a native moth. After the caterpillars hatch out, they live in silk-webbed tunnels at the soil surface, but as they mature they dig deep underground burrows to hide in. The caterpillars emerge from their burrows in late afternoon & evening, stripping the grass foliage and causing rapidly expanding bare patches.

In addition to bare patches, if you see birds pecking at the lawn, or bare patches of soil dotted with pencil-width holes, it can be a sign of porina caterpillars (the birds are searching for caterpillar 'snacks').

Grass grubs are also a destructive native lawn pest. They are the larvae of brown beetles, that mature under the soil and chew their way through the roots of your lawn. Grass grubs are C-shaped, creamy coloured grubs, with a dark brown shiny head.

Yates Lawn Grub and Porina Kill + Protect delivers excellent preventative control against porina, grass grub and other lawn pests commonly found in New Zealand.

Pro Tip:  The adults of both these lawn pests are attracted to light. It's quite common in October/November to see the grass grub beetles buzzing around the street lighting. If your outdoor lighting is close to your lawn area, try to use it sparingly and don't leave it on for extended periods.

Controlling Lawn Diseases

Mild temperatures and excess rainfall and humidity during autumn can encourage lawn diseases to strike. These diseases include brown patch, fusarium patch, dollar spot and anthracnose. Diseases can be tricky to diagnose, as symptoms can look similar to other lawn problems, like grass grubs or armyworm. If you have a browse through our ProblemSolver page, it'll help you diagnose the problem and find out the fix.

Common disease symptoms include areas of discoloured, brown, red, dead or dying patches in the lawn. Lawn diseases can also reoccur year after year, so it’s important to get them under control to keep your lawn looking good, long-term.

Here’s how to help reduce the risk of lawn diseases:

• Mow regularly to prevent a build up of thatch

• Remove grass clippings from the lawn, while weather conditions favour diseases

• Water only in the mornings, to allow the lawn to dry off during the day

• Aerate or core your lawn, to improve drainage

• Proactively treat with Yates Fungus Fighter, which contains an effective fungicide to control common lawn diseases dollar spot and rust

• Keep your grass well fed, with a lawn food that contains a good amount of potassium. Potassium is a nutrient that helps strengthen the lawn so it’s better able to resist disease infection. Yates Dynamic Lifter Lawn Food applied during autumn will also promote a lush green lawn as winter approaches. It also adds valuable organic matter into lawn soil.