---
title: Brown Patch Grass Fungus | Emerald Lawns
description: Have you seen these tan, ring-shaped spots on your turf? It's called brown spot, a fungal disease that commonly occurs in the fall due to over-watering, under-watering, and poor maintenance practices. In this blog, learn all about brown spot disease and how you can fix it!
---

[The Dirt ](https://emeraldlawns.com/blog)

# [Brown Patch Grass Fungus | Emerald Lawns](https://emeraldlawns.com/blog/brown-patch-fungus)

 Written by [Emerald Lawns](https://emeraldlawns.com/blog/author/emerald-lawns) | Sep 14, 2012

Brown Patch Fungus In Fall

The beauty of a lawn can be quickly destroyed by brown patch, a serious fungal disease that predominantly affects **St. Augustine and zoysiagrass**. [Brown patch](http://www.clemson.edu/extension/hgic/pests/plant_pests/lawns/hgic2150.html) is a turfgrass disease that is caused by the Rhizoctonia species fungus.

# When Does Brown Patch Appear?

Late spring through early fall, with peak outbreaks in late summer to early fall.

# How Can I Detect Brown Patch?

Viewing brown patch from above, it will look like a doughnut – **a ring of tan grass having a patch of green grass in the center**.

- Individual grass blades will be brown down to the crown, where the blade merges from the group, but the crown will be green.
- **Grass blades will easily pull off** of stolons in the grayish area.
- These patches can range in size from a **few inches to several feet in diameter**.

# How Do I Prevent Brown Patch?

Prevention is much easier to deal with than treatment after a fungus develops! The common themes of unwanted fungus are humid/damp conditions, over-watered lawns, dry lawns, and poorly maintained lawns.

- **[Water the proper amount, at the proper time of day](https://emeraldlawns.com/good-watering-habits/)**. Water sitting/pooling in your lawn overnight can promote fungus so try to water between midnight and 9 am, allowing it to dry before the heat of the day sets in.
- **Avoid high rates of nitrogen fertilizer** during the fall and winter. The disease-causing fungus readily attacks the lush growth of grass which nitrogen promotes.
- [**Aerating**](https://emeraldlawns.com/services/lawn-aeration/) helps to remove extra thatch and brings better air circulation and water penetration to your lawn.

# How Do I Treat Brown Patch?

To rid your turf of Brown Patch Fungus, you can apply a fungicide yourself or hire an expert. If you plan to do it yourself, check out an online tutorial to ensure efficacy:

- Inspect your application equipment prior to use
- Follow product application procedures to avoid an improper distribution rate
- Time the application just right, again following the instructions closely, for maximum optimization
- Water exactly as described

# Let’s Restore Your Turf!

[View full post](https://emeraldlawns.com/blog/brown-patch-fungus)

```json
{
  "@context" : "http://schema.org",
  "@type" : "BlogPosting",
  "author" : {
    "@type" : "Person",
    "name" : "Emerald Lawns"
  },
  "dateModified" : "2025-06-13T23:42:02.662Z",
  "datePublished" : "2012-09-14T04:00:00Z",
  "headline" : "Brown Patch Fungus",
  "image" : {
    "@type" : "ImageObject",
    "height" : 800,
    "url" : "https://47505944.fs1.hubspotusercontent-na1.net/hubfs/47505944/Imported_Blog_Media/Brown-Patch-Header.png",
    "width" : 1200
  },
  "mainEntityOfPage" : "https://emeraldlawns.com/blog/brown-patch-fungus",
  "publisher" : {
    "@type" : "Organization",
    "logo" : {
      "@type" : "ImageObject",
      "height" : 60.0,
      "url" : "https://47505944.fs1.hubspotusercontent-na1.net/hubfs/47505944/Imported_Blog_Media/EL_LOGO_BASIC_NO_TAG1-300x104.png",
      "width" : 173.07692
    },
    "name" : "The Dirt"
  }
}
```