4/19/2015 10:04 PM
I'm in Western NY and had a huge problem 8-10 years ago. We had a Cornell entomologist that did in depth study on threshold, timing and efficacy. His name is Daniel Peck he has plenty of articles.
Bottom line inWNY we spray Mid Sept.- mid Oct. this timing eliminates 2 different species and is timed with egg laying and smaller larvae ( I prefer imidacloprid then). The other timing is May in WNY, but this is timed with adult feeding and I prefer carbaryl (unfortunately earthworms don't like it).
We had 188/square foot in fairways with no visible damage other than holes from birds feasting. Our rough gets hammered with as little as 25/square foot. You'll have nothing left in the rough,but undesirable species of turf.
The aftermath was ridiculous. So many dead larvae it stunk. Dropped the HOC on fairways a click and bucketed the mess.
Good luck and check your rough and home lawn.