yellow streaked bahia

pfflyer85 – posted 17 July 2002 08:16

I have yellow streaking on my bahia (approximately 10000 sq feet). I had soil tested and applied by broadcast method 7 lbs sulphur per 1000 sq foot end of June to correct the ph as reccommended. Liquid over the counter ironite applied in July at 32ounces per 5000 sq ft and in June 16.6 lbs of 6.6.6 was applied by broadcast method per 1000 sq foot. Sod was layed last year, is mowed every week at approximately 3.5 to 4 inch height. It is watered with reclaimed water twice a week. I am now going to try a top dressing of composted cow manure. Do you have any idea what is causing the yellow swaths??? Could it be a mower problem? The grass blades appear ripped off at the top. Help, Help. Thanks

WillR – posted 17 July 2002 16:43

Well, if your getting any substaintal rain, or if you are watering deeply, you might check for root rot. You could also have a fungus.

Does the grass seem tender? Is it fragile?

seed – posted 20 July 2002 22:01

pfflyer85, yellowing is not uncommon for bahiagrass, sometimes correctable with iron, sometimes not. I have seen yellowing associated with marly, calcareous soil, high soil pH. You’ve tried to correct that with sulfur, but even if the rate is right (varies by soil type), the effect is not instantaneous. More nitrogen from cow manure will probably make the problem worse. If the mower were the problem, then the width of the deck would probably conform to the width of the yellow swaths, but I think a mower effect is unlikely. Bahiagrass leaves are tough and even with a sharp mower there will be some tearing, especially if the blade speed is slow, e.g, the motor is straining. Reclaimed water is a concern. First, depending on where you are, why are you watering the bahiagrass at this time of year? Or any time of year? Throughout most of Florida, in level areas, it survives with no irrigation. Second, how much nitrogen is in the reclaimed water? If you water with 1 inch, that’s 7770 gallons, and if you do this twice per week for one year, that’s 1.39 million pounds of water, and if the water is 15 parts per million nitrate (nitrate is 22.5% nitrogen), then that’s an extra 4.7 pounds of N per thousand square feet per year, more than you should be fertilizing bahiagrass anyway unless it’s for cattle.

Phil