help needed my sir Walter buffalo going brown in patches and thatching.

[wilederlee]

 

 

 

[EricL]

Hello @wilederlee 

Welcome to the Bunnings Workshop community. It's sensational to have you join us, and thanks for sharing your question about your buffalo lawn.

Can you please tell us what has been happening the last few weeks? Have you increased your watering schedule? Have you added fertilizer or any type of chemical to your lawn? Did you miss watering your lawn? Has your neighbour been spraying weedkiller? How long has the patching been going on? Any extra information you can share will help us diagnose what could be going on with your lawn.

If you have any other questions we can help with, please let us know.

Eric

[wilederlee]

Sir Walter buffalo lawn layed early  November, grass was going well for about 6 weeks, then started getting brown patches and thatching in areas of lawn, In other areas thinning grass. I was watering twice a day, for about 6 weeks, reducing down to once a day was inconsistent, sometimes in the morning if this was missed I watered in the afternoon. I first thought it was grubs so I used yates grub kill & protect, there was no change. Then I thought it was dog urine. I have used trojan fertiliser and the rescue wetting and no improvement on these areas the grass in other spots are green and thick. Recent rain has made it look worse and it looks like it spreading. I'm not sure what I should do now.

[EricL]

Hello @wilederlee 

From the photo and from what you have described, this looks much more like a moisture and disease issue than insects, dog urine, or nutrition. Newly laid Sir Walter buffalo is quite prone to problems when it is kept too wet for too long, especially in its first few months while the roots are still establishing. Watering twice a day for six weeks, then continuing with daily watering and occasional afternoon watering, would have kept the soil surface constantly damp. That creates ideal conditions for fungal diseases and also leads to excessive thatch and weak, shallow roots. When rain then arrives on top of that, the problem often accelerates and appears to spread, which matches what you are seeing now.

The brown, thinning patches with a matted or thatchy feel are very typical of fungal lawn disease in buffalo, commonly things like brown patch or root rot. These diseases cause grass to collapse at the base, so it looks straw-coloured and thin rather than burnt or chewed. The fact that grub treatment made no difference, fertiliser made no improvement, and rain made it worse are all strong indicators that insects and nutrients are not the primary issue. Dog urine usually creates dark green rings with dead centres, which does not match the pattern in your photo.

The first thing to do now is to stop overwatering. Even though it feels counterintuitive when grass is struggling, more water will continue to fuel the problem. At this stage, watering should only be done every two to three days, and only in the early morning, with enough water to soak the soil to around 80–100 mm. This encourages deeper roots and allows the surface to dry out between waterings, which fungi hate. Afternoon watering should be avoided completely.

The second step is to address the disease directly. A lawn fungicide suitable for buffalo such as Yates 150g Mancozeb Plus Garden Fungicide And Miticide, applied according to label directions, is the most effective way to halt the spread. I suggest diluting the chemical in a Silvan 5L ECO Hand Sprayer. Without this, the affected patches often continue to enlarge even if watering is corrected, particularly in warm, humid conditions. Once the disease pressure is reduced, the healthy grass around the patches can start to recover and grow back in.

You should also lightly mow if the lawn is tall enough, making sure the mower blades are sharp and not removing more than one third of the leaf at a time. This improves airflow and reduces humidity at the soil surface. Avoid further fertilising for now, especially high-nitrogen products, as these can worsen fungal issues. The Trojan fertiliser you applied will not fix this type of problem and may have unintentionally encouraged softer, more disease-prone growth.

After the disease is under control and conditions dry out, the affected areas can be gently raked to remove dead material and encourage new runners to spread back in. Sir Walter is slow to recover but it does recover well once conditions are right. If some patches are very thin, they can be top dressed lightly with sandy soil to help runners re-establish.

Please remember to wear personal protection such as gloves, goggles and mask when spraying your lawn.

If you need further assistance, please let us know.

Eric

[wilederlee]

Hi Eric,

Thankyou for all you're advice!

I have 2 Cavelier's dogs, how safe is yates 150g mancozeb plus garden fungicide and miticide.

[EricL]

Hello @wilederlee 

Please note that Yates 150g Mancozeb Plus Garden Fungicide And Miticide is toxic to pets. It would be best to keep the dogs away from the lawn for at least two days before allowing them back outside. Keep in mind that this is dependent on the weather and if the lawn is still wet or moist after two days, please keep them away from the lawn. If there is a dog park near your area, it would be best to bring them there to get their exercise.

If you need further assistance, please let us know.

Eric