Overnight lawn camouflaging phenomenon (10-23-2006)
These past few crisp mornings prompts me to mention prior to the occurrence a phenomenon that generates several calls each fall. If this year holds true as in the past years, I will receive several calls concerning weird camouflage patterns on turf, particularly hybrid Bermudagrassafter, the first light killing frost.
Now I have had some fun with a couple of callers I know personally. I explained to them that our military has been quietly spraying at night to test a new defense system to camouflage lawns from terrorist attack. And I believe one or two callers have taken me seriously. But in reality, this phenomenon is nothing to worry about. Your lawn has not been invaded by the military or some terrible insect or fungus. It is simply the results of the first light frost or two of fall.
Heat is absorbed into the soil during the day and radiates off at night through the dense canopy of leaf blades, stolons, etc. in these somewhat zigzag patterns. The small difference in temperatures is enough for frost to develop and kill leaf tissue in spots where the temperature has dropped low enough, but not in others. Generally, the denser and thicker the turf canopies the more likely for this phenomenon to occur. Once we get a hard freeze with a widespread heavy killing frost the camouflage patterns will disappear.
Published October 23, 2006
