In My Garden Blog
June 19, 2008
Lower South
By
Skip Richter,
Austin, TX
Take-all root rot causes a general dieback of affected turf grasses.
Take-All Root Rot
Growing a beautiful lawn has its challenges. There's the need to water, the challenge of weed invasions, and various insects and diseases that can show up to hamper your dream of a beautiful green carpet. However, in recent years we have been dealing with a particular disease here in the south that affects St. Augustine grass and bermudagrass but can also attack zoysia and centipede. This disease is called take-all root rot or take-all patch.
Unlike most other turf diseases, it doesn't just do some aesthetic damage, leaving the turf to recover. It kills turf, and as its name implies, it can take out a large part of a lawn. It's caused by a fungus that gets the upper hand when turf is stressed. Drought, shade, and weed killers are all common causes of turf grass stress that may lead to take-all infection.
This disease kills roots and runners, leaving the lawn declining quite rapidly in the heat. Unlike chinch bugs, symptoms don't usually begin adjacent to a curb or sidewalk but are rather random in location and irregular in shape and progression throughout the lawn.
The Remedies
There are two basic approaches to dealing with take-all: prevention and treatment. Avoid stressing your lawn and you will likely avoid this disease becoming a factor. Broadleaf weed killers are very stressful to St. Augustine, for example, when temperatures rise into the mid 80s. Avoid using these products after the cool spring period gives way to rising temperatures.
I let my lawn get very drought stressed a couple of years ago during the long, hot summer season. The next year I experienced a serious take-all problem. Once you have the disease in the lawn, your control options are cultural and chemical. First of all, you will want to provide adequate soil moisture without overwatering to help the grass plants survive with their limited root systems. Avoid overfertilizing but make sure and provide moderate nutrition to help keep the plants reasonably vigorous.
Research in several Texas trials has shown that peat moss applied at a rate of one 3.4-cubic-foot bale per 1,000 square feet was effective in suppressing take-all. One trial showed that the inclusion of iron in the peat application was even more effective. There are special rolling drum spreaders for applying peat moss, and some lawn care companies have compost blowers that can be used.
After applying the peat moss, water the area well. Applications can be made at any time, but in lawns with take-all problems it is especially important to make the applications in early fall to mid-fall or mid-spring.
There are several chemical treatments available through lawn care companies or over the counter at garden centers for this disease. These have shown some effectiveness, but in some cases they can inhibit grass regrowth. All things considered, I find the peat moss approach to be the most natural and effective option. Just remember to avoid stressing the grass or you'll be providing take-all the opportunity to strike again.
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Comments on Take-All Root Rot
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Linda B in SC
Boy, does this sound like my lawn. It has been in decline for
several years. And maybe not surprising this started 'after' I had a
lawn service doing my yard. Big mistake I fear. Too much either too
soon or too late. I am paying for it now.
Interesting article and I am in the process of getting some help
putting down Peat Moss but did not think of placing it on this
heavy. So thanks from someone that needed a boost on this project.
LB
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Skip
Linda, I would also suggest you contact your County Extension Office
and ask about bringing in a sample for diagnosis. They may be able
to help you diagnose the problem and build a more complete plan for
getting the lawn in top shape again. I hope you can turn your lawn
around soon!
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Skip
Linda, I would also suggest you contact your County Extension Office
and ask about bringing in a sample for diagnosis. They may be able
to help you diagnose the problem and build a more complete plan for
getting the lawn in top shape again. I hope you can turn your lawn
around soon!
add a comment
Skip
Linda, I would also suggest you contact your County Extension Office
and ask about bringing in a sample for diagnosis. They may be able
to help you diagnose the problem and build a more complete plan for
getting the lawn in top shape again. I hope you can turn your lawn
around soon!
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cari
very new to lawn care--what is peat moss? Do you lay it down or is
it seed? Our lawn seems to be invaded with this take-all---yikes!
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Cari
Sphagnum peat is the ground up product that is mined from peat bogs.
It is much like the fluffy brown material in most seed starting
mixes. Check with a full service garden center about them ordering a
compressed bale for you or check online for sources. These bales are
plastic bags of the compressed product about the same size and shape
as a bale of hay.
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Amy
Howdy from Dallas... This sounds like what we had last year...
whole lawn died out, and there were even large fungal masses at some
places on the top of the soil (hard as a rock, flat, creamy-yellow,
anywhere from 4" to 12" across)... So we dug out the masses, raked
as much of the dead thatch and disease out as we could, then applied
50lb of dried molases & watered it in well to stimulate growth of
the good, fungus eating bacteria... next year the lawn recovered
just fine. Actually it's going gang-busters this year. Maybe
someone more knowledgeable can explain the microbiotics involved?
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