Ten years ago, when I first came to Houston to start working on the GardenLine radio program, the problem of Take All Patch in lawns was something of a myth. Did it really exist? If you were to ask a garden advice blabbermouth, or supposed lawn expert how to control (or for that matter how to diagnose ) such a problem, we usually sloughed it off as a misdiagnosis.
But now, Take All Patch (Gaeumannomyces graminis var. graminis) is obviously a very real problem in both St. Augustine and Bermuda grass yards throughout Texas. Not only is it called Take All Patch (TAP), it is also bandied about as Take All Root Rot (TARR).
According to Texas A&M plant pathologists, the main disease is active in the fall and spring when the soil temperatures are in the 60- to 65-degree range. At this time of the year, the fungi attacks the plant's root system, weakening it as it goes into the winter and summer stress periods. This disease appears to be particularly active on plants that have been become stressed for one reason or the other. You might get some serious arguments in the Houston area about whether summer time seems to be the most active time for TAP/TARR
Take All Patch (TAP) first rears its head with a lot of yellow discoloration in St. Augustine blades. Hence the misdiagnosis: First, people think it's a simple Iron Defeciency or possibly something as simple as Chinch Bug damage. So, they throw some iron or insectiscide at it, but nothing really changes and the problem actually grows worse.
When you finally get down to look at the roots of the grass they are short, blackened and rotted, and the stolons (runners) can easily be lifted from the soil due to the poor root system. For the past few years, on the GardenLine radio program, I have refered to this lack of roots as "lifting the turf up as if it is a bad toupee." Because of the lack of roots, the yellow grass eventually browns and thins out.
But what exactly is causing Take All Patch? That is still up for debate, and research doesn't seem to have pinpointed one overall cure either. Dr. Jim McAffee, a turfgrass expert with the Texas Cooperative Extension Service in Dallas says that TAP is caused by a combination of factors, including environmental stress, disease activity, a lack of acidity in the soil, too much nitrogen and, in some cases, excess levels of phosphorus.
According to McAfee, for the last several years, summers have been above average in temperature and below average in rainfall. While this combination places a huge amount of stress on all the turfgrasses used in home lawns, St. Augustine grass has suffered the most. Oddly enough the best time to treat for Take-All Root Rot is in the fall and spring when the soil temperatures are in the 60- to 65-degree temperature range according to turfgrass researchers. Chemical treatments such as Heritage, Rubigan and BannerMaxx have shown some control for this particular problem, but are very expensive for the average homeowner, if not downright hard to find.
Foster Watts with the Fertilome/HiYield companies backed up his method with some strong research that shows a granular application of Myclobutanil (ex: Fertilome F-Stop or GreenLight Fung Away) followed by one of the lesser expensive Banner-based systemic fungicides (Ex: anything with the systemic fungicide propaconazole (Ex: Fertilome Liquid Systemic Fungicide; Bonide Infuse) seems to have credible control abilities. This is also something that is done at least twice in a 60 day period. The most serious drawback to this method, is that if it doesn't work right away, and you keep applying and re-applying chemical fungicides, you will be destroying the microbial life of the soil.
Recent research by Dr. Phil Colbaugh at the Dallas-based A&M Turfgrass researcher facility has shown that use of a composted cow manure product on this disease does have some success. Still others are using a composted Peat Moss application for their control measure, and again the results are very promising. The hardest part of the Peat Moss application is that you have use a bonafide Peat spreader, which are few and far between. Otherwise, trying to spread Peat by hand is frustrating at best. Here's is the link for Dr. Colbaugh's research (.pdf format)...
If it makes you feel any better I have suffered from Take All Patch before, and even the God of all garden advice himself, Neil Sperry, has suffered from Take All Patch as well. Neil is a huge fan of Dr. Colbaugh's Peat Moss treatment. Here is an article from Neil's website about the problem and his success story at control
And in case you have not ordered it yet, here's the link for ordering the listener discounted version of my new book "Gulf Coast Gardening with Randy Lemmon."
Only as an email tip subscriber can you have access to ordering this book at a discount. Okay, let's be honest here - if you would like to share the above link with anyone else, who is not subscribed to the email tips, they too can enjoy the only discount available for this book until the end of August.
Until next issue, here's to
Great Gardening from the GardenLine, heard
exclusively weekend mornings from 8 to noon
on Talkradio 950 KPRC.