The Grasshopper's gazette- December 2019

COOL WEATHER

This beautiful cool weather can bring some not so “cool” spots in your lawn. The brown patches is actually a fungus called “brown patch.” This fungus lies dormant in your soil until the weather changes, whether it is from warm to cool or cool to warm. If this fungus isn’t mitigated it can end up making your entire lawn look like leopard print.

IDENTIFICATION

Brown patch is identifiable by it’s mid to large circular area anywhere from one foot to three feet in diameter of brown grass with a yellow or orange ring around the outer edge. The brown grass in the center can be thin or dead with lesions. This disease is caused by the Rhizoctonia fungus. It will usually show up in the fall and spring time here in central Florida when there are cool nights and warm days. 

CAUSES OF BROWN PATCH

As with most fungi, Rhizoctonia thrives in a wet, humid environment. We experienced a lot of rain this summer! If there was a low lying area in your yard that did not allow for proper drainage, it is more susceptible to harboring the brown patch fungus. This fungus will wait until there is a change in temperature to be become “active” and noticeable. Brown patch can be spread to other areas of your lawn or even neighboring lawns by walking and mowing. 

PREVENTION

The best offense is a good defense in this situation. Brown patch can be contained and treated with the proper use of fungicides . But, the best thing for the grass is to ensure your lawn has proper drainage and an appropriate watering schedule. Shade areas require less water than sunny areas. Also, low lying ditches that are known to hold water should have drains installed to ensure proper water movement allowing for the soil to “dry out” and prevent the Rhizoctonia from establishing in the first place. One of the best ways to help make sure your lawn has proper drainage is to do a spring aeration. This sets the foundation to your grass on the right food just before peak growing season.

BROWN PATCH VS DOLLAR SPOT

There is another fungus that can show up this time of year and is sometimes lumped in with brown patch, it is “dollar spot.” While they share a similar appearance, dollar spot is only about the size of a dollar coin. Dollar spot is caused by a different fungal pathogen named, Rutstroemiaceae. While these spots can sometime blend together to look larger they will generally stay in the in silver dollar size. The best thing you can do for your lawn is to have a licensed lawn care professional over to give you a consultation.