Large dead spots in lawn - Ask Extension
Our lawn has developed large dead areas again this year. It seems to happen every year; we start out great in the spring but by the time we get to Sep...
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Large dead spots in lawn #277113
Asked September 10, 2015, 12:13 PM EDT
Our lawn has developed large dead areas again this year. It seems to happen every year; we start out great in the spring but by the time we get to Sep it look terrible. A picture is attached below. We have several ant colonies ... could that be responsible? Is its fungus? And what can we do to get rid of them. Any help would be greatly appreciated. Thank you
Wicomico County Maryland
Expert Response
Lawns in Maryland are usually comprised of tall fescue (or fine fescue in the shade). These are cool season grasses, which means they grow best in cool moist conditions, i.e. spring and fall. In drought, tall fescue will go dormant, but it has the ability to green up quickly as soon as it rains because the roots are still healthy. (Though some will die in a bad drought. Unfortunately, we've been having a bad drought.) This is normal.
We doubt the ant colonies are your main problem. Ant colonies can indicate dry soil, however.
The problem is also probably not a fungus. However, fertilizing in the early spring can promote an overly-lush lawn which is tender and weak and susceptible to fungal problem. For this reason, we recommend fertilizing in the fall primarily.
Your lawn may need overseeding to thicken it up because it has slowly thinned over the years. The pH may be too low--so you need to get a soil test and see if and how much lime it needs (don't try to guess.) Info on soil testing is on the right side of our homepage.
Carefully read through the following pub. It will tell you what needs to be done for a successful lawn and you can compare those steps with your lawn because not following any of the recommendations can lead to problems: http://extension.umd.edu/sites/default/files/_images/programs/hgic/Publications/HG102%20Lawn%20Estab...:
The good news is that fall is the best time to oversee and fertilize because then the new seedlings have three relatively cool moist seasons to get established before they hit a tough Maryland summer. .
ECN
We doubt the ant colonies are your main problem. Ant colonies can indicate dry soil, however.
The problem is also probably not a fungus. However, fertilizing in the early spring can promote an overly-lush lawn which is tender and weak and susceptible to fungal problem. For this reason, we recommend fertilizing in the fall primarily.
Your lawn may need overseeding to thicken it up because it has slowly thinned over the years. The pH may be too low--so you need to get a soil test and see if and how much lime it needs (don't try to guess.) Info on soil testing is on the right side of our homepage.
Carefully read through the following pub. It will tell you what needs to be done for a successful lawn and you can compare those steps with your lawn because not following any of the recommendations can lead to problems: http://extension.umd.edu/sites/default/files/_images/programs/hgic/Publications/HG102%20Lawn%20Estab...:
The good news is that fall is the best time to oversee and fertilize because then the new seedlings have three relatively cool moist seasons to get established before they hit a tough Maryland summer. .
ECN
