In the North, we often hear how sub-zero weather will suppress the bug population. "Not like the South."
Nonsense, there is more to it than that. Yes, I clearly remember discovering that cockroaches are outdoor bugs in Tampa. The critter picked up my foot as I sat on a park bench ... seems that I was keeping him from a piece of popcorn

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Okay, a mild winter here, 2014 -'15. I thought that the leafhoppers/spittle bugs would be making a mess of everything, starting with the acres of alfalfa around the big veggie garden. Nope. Oh, they were around but not like some years.
Not one leaf miner have I come across in either the spinach or beets. Indoors, and most every year, the dang fruit flies move in with the ripe melons. I had plenty of ripe melons but only a few fruit flies.
The locust tree borers have been everywhere and I worry about our drought-stressed trees and what future seasons will show. But, simple answers are often not the right ones, like subzero would have killed them ...
I'm reminded of what an entomologist from outside the US once told me: all tree deaths were being blamed on gypsy moths when there were multiple causes. He noted that the bandwagon to aerial spray them came just as DDT was banned. The government bought up much of the remaining stocks and sprayed it over many square miles of forests.
Simple answers lead off into tangled paths, at times.
Steve