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1996, No. 7
SUMMER DISEASES DEVELOPING IN ILLINOIS
A number of diseases have developed so far this summer.
Some of these problems are common, while others are more unusual.
First, the common problems.
Take-all patch was severe on bentgrasses a month ago, but should be gone by now.
Some scars will remain if this disease attacked your turf, and you can expect it to return when cool, wet soil conditions return.
Take-all patch is a devastating disease and difficult to control.
If you had this disease, contact us and we will assist you with it.
Basal stem rot, or anthracnose, was also active during June, but it too should be causing few problems now.
It will return in the fall when cool, wet conditions are accompanied by some turf stress.
Watch for this disease on annual bluegrass, but don't be surprised if you see it on bentgrass too.
Summer patch of Kentucky bluegrass is a destructive disease that is visible in turf now! You can recognize this disease by rings or patches of grass that are sunken, a little bluish or even straw brown.
If the summer turns hot and dry, the symptoms will intensify.
There isn't much you can do about the disease now.
The time to control it is in the spring and fall.
Fairy rings have been abundant during the past two months and will continue to appear if we get sufficient rain and heat.
They are difficult to control.
There are fungicides that have shown effectiveness on some fairy rings, but with so many different types of fungi causing them, your chances of success are slight.
An uncommon leaf blight has been seen in several areas of the Midwest on Kentucky bluegrass.
The disease is Leptosphaerulina leaf blight.
It is a disease that affects the grass leaves; it generally develops when turfgrass blades remain wet for long periods of time, and the temperature in the turf canopy is high.
You can recognize this disease by the formation of tan or necrotic tips on leaf blades.
Also, look for small black specks in the dead leaf tissue.
The disease starts at the cut end and progresses down the leaf.
Frequent mowing, proper fertilization, and irrigation management will control this disease.
Fungicides are also effective, but often not necessary.
Dollar spot and brown patch are also active, but these are common and expected.
The severity at this time is not great in the Midwest.
Likewise, Pythium blight pressure seems to be generally low, but some turf managers have experienced local hot spots.
If you have any questions, contact one of us for consultation and relief.
(H.T. WILKINSON AND R.T. KANE)
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