Q. I have some large dead areas
in my lawn. I don’t think it’s an insect problem. Watering is at 2 AM and 7 AM.
This was my first lawn problem in 16 years!
in my lawn. I don’t think it’s an insect problem. Watering is at 2 AM and 7 AM.
This was my first lawn problem in 16 years!
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| Unusual pattern for dead grass. Too random for irrigation I think. |
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| This picture you start to see the “frogeye” disease pattern. Looks like it could be a chemical spill. |
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| Here is where “frogeye” starts to make an impression. But its over. |
A. I looked at the
pictures you sent, but the last picture was the most “telling” to me. I think
your lawn had a disease problem that is now finished. Don’t do anything now! Let
me tell you why I came to that conclusion.
pictures you sent, but the last picture was the most “telling” to me. I think
your lawn had a disease problem that is now finished. Don’t do anything now! Let
me tell you why I came to that conclusion.
Insect problems here are not like those “rolling back
like a carpet” problems described in books and online. Those descriptions apply
to Kentucky bluegrass damaged by white grubs. We have grubs, but we don’t have
much bluegrass anymore. Our lawns are 95% tall fescue and tall fescue reacts
differently to insect damage. It pulls out like loose hair from an old animal
skin. Plus, the pattern of dying grass does not resemble insect damage.
like a carpet” problems described in books and online. Those descriptions apply
to Kentucky bluegrass damaged by white grubs. We have grubs, but we don’t have
much bluegrass anymore. Our lawns are 95% tall fescue and tall fescue reacts
differently to insect damage. It pulls out like loose hair from an old animal
skin. Plus, the pattern of dying grass does not resemble insect damage.
I first thought the brown spots were an irrigation
problem, but the pattern doesn’t fit an irrigation problem. With irrigation
problems, dead or damaged areas are in a pattern that relates to the location of
sprinkler heads. I didn’t know where the sprinkler heads were, but the damage
was irregular, so I ruled out irrigation.
problem, but the pattern doesn’t fit an irrigation problem. With irrigation
problems, dead or damaged areas are in a pattern that relates to the location of
sprinkler heads. I didn’t know where the sprinkler heads were, but the damage
was irregular, so I ruled out irrigation.
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| Irrigation problems are nearly always easy to see how they connect to the sprinklers. |
The
pattern does, however, resemble a chemical spill flowing downhill and damaging
the grass in its path. It was a possibility, but the last picture looked like
advanced stages of a disease problem. We used to call this disease Fusarium
blight or “frogeye”. This disease has since been renamed Necrotic Ring Spot. I
thought “frogeye” was much more descriptive.
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| Seldom will you see it this obvious but this is frogeye. See how it got its name? In advanced stages these dead areas can become one but you still look for little patches of green grass that would still be there. Sometimes its hard to see them. |
What led me in the direction toward disease were the
small patches of green grass still alive but surrounded by dead grass. These
small green patches of grass are how “frogeye”, now Necrotic Ring Spot, got its
name.
small patches of green grass still alive but surrounded by dead grass. These
small green patches of grass are how “frogeye”, now Necrotic Ring Spot, got its
name.
From the pictures, it looks like the disease has run its
course and the grass that’s alive is healthy. I say this because the grass
surrounding the dead areas appears healthy. This is the way lawn diseases
usually work. They have a window of opportunity, when the weather is right for
the disease to spread, and it takes off. The weather changes and the disease
stops.
course and the grass that’s alive is healthy. I say this because the grass
surrounding the dead areas appears healthy. This is the way lawn diseases
usually work. They have a window of opportunity, when the weather is right for
the disease to spread, and it takes off. The weather changes and the disease
stops.
You would be wasting your money to apply a fungicide now that
it’s over. But, don’t disturb the brown, dead grass and leave it alone until
fall. If you remove it now, it opens the soil to invasion by Bermudagrass.
Bermudagrass loves sunshine, bare soil and water. It hates shade. Wait until
the weather cools in late September or October, remove the dead grass and
either seed or sod these areas.
it’s over. But, don’t disturb the brown, dead grass and leave it alone until
fall. If you remove it now, it opens the soil to invasion by Bermudagrass.
Bermudagrass loves sunshine, bare soil and water. It hates shade. Wait until
the weather cools in late September or October, remove the dead grass and
either seed or sod these areas.