Magnaporthe Poae Lawn Disease

early spring lawn care tips

lawn diseaseSo, what is Magnaporthe Poae Lawn Disease? Firstly, like all other common lawn diseases, it is a fungus. It causes a turf grass disease that is known commonly as Summer Patch or Poa Patch.

Poa Patch will usually become visible and noticeable between the months of June and September. However, it can also can appear throughout the year at any point. The main factors that encourage this intruder are heat and humidity.

Bluegrass, Fescues, and Bentgrass are the 3 turf types most commonly afflicted by poa patch. Fortunately, none of these are terribly popular in the North Texas reason. However, it’s still good to know the warning signs, especially if you have a yard with mixed turf.

If it is a mild infection and the turfgrass is able to recover on its own, you may not even notice it before it’s gone. But if it’s doing serious damage to your lawn, it’s good to know what to look for.

Things to Look Out For:

  • Turf base turning brown or black
  • Yellow patches or streaks growing and joining together
  • High heat and humidity
  • Cutting grass too short
  • Using too much nitrogen
  • Low spots with poor drainage


Poa Patch rings can join together to form larger, more irregular spots and streaks. If allowed to progress, the infection can lead to a condition called Dead Patch. Dead Patch will actually kill the lawn’s roots, so we want to stop it before getting to that point.

Depending on how you treat your grass, you may have summer rings and not know it until it has spread for awhile. This is because it first appears at the very base of the grass, making it difficult to see without looking closely. If the base of your grass is turning dark brown or black, this means you have an issue that needs to be addressed immediately.

Turf Necrotic Ring Spot Disease is another fungal disease worth learning about, for optimal lawn health.

Avoid Scalping

When it comes to treating magnaporthe poae disease, you can do a couple of things to prevent and solve the issue at hand.

Make sure you don’t cut more than 1/3 the length of your grass when you mow. This is true regardless of the beginning length, as moving more than that percentage makes the blades themselves more vulnerable.

If you cut shorter than this, it can cause root damage and “scalp” the grass. Scalped, damage grass is weaker and more vulnerable to infection or disease.

Excessive Nitrogen

It’s also a good precaution to not go overboard with nitrogen-based fertilizer in the summer. This can be tricky, as North Texas soils generally need nitrogen-rich fertilizers. However, there is always such thing as too much of a good thing. Excessive nitrogen can promote the grown and spreading of some fungal diseases, including Poa Patch.

Watering and Drainage

Make sure you water lightly and often in the hot weather. When you water, you want to avoid watering the areas where Poa Patch is present, this can hasten the spread of the disease.

Another key step when dealing with Poa Patch is soil drainage. Having soil that is blocked and unable to breathe is a key ingredient for the growth of magnoporthe poae fungi. Our Aeration Service can also assist in addressing fungal diseases, as aerating helps the topsoil breathe.

Be mindful of low areas in your lawn with poor drainage. This includes low spots around your home and gardens, as well as areas with high traffic. If you find that you need to have parts of your lawn leveled, contact JC’s Landscaping LLC for a free service quote.


Finally, a great tip when dealing with Poa Patch is fighting back with fungicides. Depending on the severity and how badly the disease has taken over the grass, you have multiple options.

Picture of Janice Nelson

Janice Nelson

Leave a Reply

Your email address will not be published. Required fields are marked *

For security, use of Google's reCAPTCHA service is required which is subject to the Google Privacy Policy and Terms of Use.

I agree to these terms.

This site uses Akismet to reduce spam. Learn how your comment data is processed.