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grassmasterswilson
07-18-2012, 05:31 PM
So we had a nice 3 week stretch of drought and 100 degree days. Then we had a week in the 90s and about 5-6 inches or rain for the week. Now we are back into dry and 90s.

Shortly after the rain I noticed what I think is diesease on mostly my hybrid bermuda. I just assume that because of all the rain that the leaf blade stayed wet. Is this dollar spot?

Think Green
07-18-2012, 05:51 PM
Wilson,
Take some dead stems and some stems from the surrounding areas and separate them. Look at them under a magnifying glass for spots and lesions.
A state or university test is the best way to detect these diseases, as I am seeing this start to infiltrate our bermuda's also. It is so bad that I am afraid that the recovery process and the time involved is against us. Not enough time left in the summer to fill in the spots.
I wish this response was more informative. I am needing to know also, but I don't have the spare time to send all these specimens off to state and wait for a diagnosis. By the time I get the results back, the use of fungicides will only cease the spread temporarily and not allow time for regrowth.

Brett Thomas
07-18-2012, 06:54 PM
Pythium blight always works from the crown of the plant and works outward towards the leaf tip

RAlmaroad
07-18-2012, 07:08 PM
If you could possibly photograph a section very close up using good sunlight with plants against a pure white background (paper laid in a good angle to catch the sun), there are several very good guys that can recognize the many fungi that we deal with. Some of only see brown patch and TARR, but other have far more vast experience. Close up with large leaf patterns, roots, crown are all important. Look for frog eyes or brown patches with a different color in the center. Post these and let the more experienced guys help. Could save a lawn and I totally agree that the universities are too slow to return a positive finding on the fungus.

coolluv
07-19-2012, 06:15 AM
Drought Stress.

Dave...

cgaengineer
07-19-2012, 06:20 AM
Drought Stress.

Dave...

I agree.
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RigglePLC
07-19-2012, 11:53 AM
Drought would affect all the grass--not kill some and leave the rest. Perhaps there are two kinds of grass--one susceptible to whatever is the cause. And one not susceptible. Is this all the same grass? Hybrid Bermuda?
No rye? No poa? No fescue? No common Bermuda?
The odd pattern of damage means something. I don't know what.

georgialawn88
07-19-2012, 12:15 PM
i have spots in my yard like that. about 3 or 4 spots not near as big. they showed up literally over night. The grass is completely dead about 8 inched by 12 inches. Ive never sen that before. It looks identical. but i have a irrigation system so it shouldn't be due to stress. i dunno... but whatever that yard has mine looks close just not as bad.

cgaengineer
07-19-2012, 12:17 PM
Drought would affect all the grass--not kill some and leave the rest. Perhaps there are two kinds of grass--one susceptible to whatever is the cause. And one not susceptible. Is this all the same grass? Hybrid Bermuda?
No rye? No poa? No fescue? No common Bermuda?
The odd pattern of damage means something. I don't know what.

It will leave spots just like this in Bermuda...I know it for a fact. Had one lawn that looked just like that...added water and it is now fine.
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RAlmaroad
07-19-2012, 12:45 PM
Here's an excellent report on fungi and fungicide. Good supporting info on IPM and how fungicides react to soil pH. Give it a read. http://www.ca.uky.edu/agc/pubs/ppa/ppa1/ppa1.pdf

macgyver_GA
07-19-2012, 01:15 PM
Definitely drought stress. A few of the lawns I maintain had spots like this because the customers didn't water at all during the record 100+ degree temps, no rainfall for about 2-3 weeks, and low humidity. The lawns only did it in spots with 100% full sun all day. The bermuda is already shooting up new growth since we've been getting dumped on with rain the last week and a half and the temps are down and humidity up.

Driving around here, I have noticed a lot of the non-irrigated hybrid bermuda turf has done the same. It's all starting to come back. Give it a few weeks and it will look much better.

grassmasterswilson
07-19-2012, 02:09 PM
I thought drought at first but signs showed up after all the rain before the rain the lawn showed total browning due to drought of course we are back in a crunchy state now sonit doeant really matter

The couple i have really noticed it in are ones that were sodded at some point with a hybrid. They have irrigation and use it. I advised them to cut back some or make sure it was running early in the morning so the lawn wasn't wet all the time. All are Bermuda with no other species.



UOTE=RigglePLC;4475409]Drought would affect all the grass--not kill some and leave the rest. Perhaps there are two kinds of grass--one susceptible to whatever is the cause. And one not susceptible. Is this all the same grass? Hybrid Bermuda?
No rye? No poa? No fescue? No common Bermuda?
The odd pattern of damage means something. I don't know what.[/QUOTE]
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grassmasterswilson
07-19-2012, 02:11 PM
It is back to being really dry here so at least te symptoms are a obvious. Hopefully some good rain will come in hope of being able to grow te spots back.
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cgaengineer
07-19-2012, 03:57 PM
Just because they are irrigating doesn't mean it's enough.
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coolluv
07-19-2012, 04:04 PM
Drought would affect all the grass--not kill some and leave the rest. Perhaps there are two kinds of grass--one susceptible to whatever is the cause. And one not susceptible. Is this all the same grass? Hybrid Bermuda?
No rye? No poa? No fescue? No common Bermuda?
The odd pattern of damage means something. I don't know what.

I can't see those spots from here, but from what the OP posted it looks like drought stress. The Bermuda lawns around here looked just like that a week or so ago. Just burnt patches scattered here and there. Why? Could be a bunch of reasons. Bad soil under those areas. Close to a driveway or road. Slope area, poor drainage area and on and on.

Bermuda is different from what your probably used too. Sure the whole lawn will go brown eventually, but the most stressed spots will show up first. Like I said, many many lawns looked just like that a week or so ago.

Without closer pics of the blades...thats my guess from down here in Atlanta.

Dave...

coolluv
07-19-2012, 04:05 PM
I agree.
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What the Hell do you know!

Dave...

georgialawn88
07-19-2012, 04:15 PM
I'm out of town but i do hope that it is drought stress. ill update mine when i get back. we have been having a ton of rain

macgyver_GA
07-19-2012, 04:38 PM
Just because they are irrigating doesn't mean it's enough.
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Got that right... It was tough keeping up with it on my personal lawn. It seemed like we were getting jipped on rain at my house in Canton/Ball Ground. All the storms were going around us. We didn't get a good heavy long rain until last thursday.

cgaengineer
07-19-2012, 04:45 PM
What the Hell do you know!

Dave...

I don't know anything...but I do know that brown spots in Bermuda are often misdiagnosed as a fungus and when the fungicide is applied and the lawn is watered it magically turns green...not from curing fungus...because it needed aqua.
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cgaengineer
07-19-2012, 04:48 PM
I can't see those spots from here, but from what the OP posted it looks like drought stress. The Bermuda lawns around here looked just like that a week or so ago. Just burnt patches scattered here and there. Why? Could be a bunch of reasons. Bad soil under those areas. Close to a driveway or road. Slope area, poor drainage area and on and on.

Bermuda is different from what your probably used too. Sure the whole lawn will go brown eventually, but the most stressed spots will show up first. Like I said, many many lawns looked just like that a week or so ago.

Without closer pics of the blades...thats my guess from down here in Atlanta.

Dave...

This is the correct info...But hey, what do I know...I water my lawn in the evenings!
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Think Green
07-19-2012, 07:09 PM
I agree with all as my customers that do not have a irrigation system. These irregular spots appear mostly on the concrete street sides and around the driveways and sidewalks. Complete thorough coverage and penetration of moisture is another topic of deep discussion on this forum. I have irrigated lawns that is watered 3 days a week at 30-35 minutes per station..........good coverage with great curtains of precipitation.......same issues. Changed the watering to 5 days a week at 20 minutes per station.......same problem. When the precipitation is evaporating faster than the soil can receive it, then the soil underneath is either to compact or sandy. Some of my lawns is on a golf course plateau..........just an inch underneath the sod is a rocky base. Crappy for holding moisture and great for holding heat. Poor growing conditions is usually the culprit and others may advise the addition of top dressing.