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How to Diagnose Lawn Problems

By Tanya Khan ; Updated September 21, 2017

Every homeowner strives to make his or her lawn resemble a professional golf course. While this can be achieved with plenty of hard work and commitment, lawns are sometimes plagued by diseases that reduce their appeal. Lawn damage can be caused by a variety of culprits, ranging from insects, pet urine, and foot traffic to over or under watering or feeding. Careful diagnosis is essential for treating lawn damage correctly and preventing it from occurring again.

Walk through your lawn to determine any visible damage that cannot be seen from afar. Look for brown, burnt or dead spots, yellow circular spots, grass blades with red threads running through them or for an ant infestation. You may find one or two affected patches, or several of them all through the lawn.

Bend down and look for bugs or insects at the base of your grass blades. Bugs such as aphids, army worms, beetles and billbugs eat grass and roots, reduce the appearance of a lawn and can ruin it completely. To counter the infestation, purchase grass pesticide from your local nursery and follow label instructions to apply it over your lawn.

Prevent dogs from urinating on your grass. Dogs, especially females, have a high concentration of nitrogen in their urine and create small circular brown patches in the lawn, eventually burning it. Douse the urinated patch with water immediately to dilute and wash it away. Take your pets for a walk so they can relieve themselves, or insert stakes along your lawn and wind chicken wire around them.

Other causes for dry spots can be lack of moisture, over fertilizing, or thatch--an accumulation and buildup of debris and dead grass on soil surface. Heavy doses of fertilizer and applying it in hot weather or on wet grass can cause brow spots. Rent a dethatcher or use a rake to remove thatch when it reaches a height of 1 inch.

Fungal diseases cause grass to turn yellowish-brown or form red threads that run the length of grass blades. Purchase fungicide or an organic corn-gluten mix from your local nursery, and follow label instructions to apply it over the affected area. This will weaken the fungi and restore the grass. Over watering your lawn also creates a suitable environment for fungal disease to develop. Water infrequently, but deeply.

Weeds are a common problem in lawns, growing alongside grass and competing for nutrients. Remove weeds by pulling them out by the roots by hand or with a hoe, or applying a broad spectrum herbicide over the area to kill them.


Things You Will Need

  • Gloves
  • Pesticide
  • Garden hose
  • Stakes
  • Chicken wire
  • Dethatcher
  • Fungicide
  • Corn-gluten mix
  • Hoe
  • Herbicide


  • Mow the grass frequently, and keep the grass to a height of 2 to 4 inches. Mowing the grass too short will make it susceptible to disease, while tall grass will retain moisture and fail to dry quickly.

About the Author


Tanya Khan is a freelance author and consultant, having written numerous articles for various online and print sources. She has a Master of Business Administration in marketing but her passion lies in writing.