Thrips advice

Hewitt&son

Evening all.

I appear to be having a problem with a greenhouse thrips infestation in my laurel hedge and would like a bit of advice please. I've tried putting a photo of them on but can't for some reason but I know that's exactly what they are. 

The hedge is about 12 feet tall and 50 feet long and I'm concerned I'm going to lose the lot based on what's already happened. The thrips are on every leaf as far as I can see and I'd like to know if I'd be best spraying the lot, remove the lot or leave it and hope that we have a cold enough winter to kill the little blighters off. I'd rather not spray as it would be a massive task and I also run the risk if losing any beneficial creatures that live there too. I don't want to have to remove them all as that would be a nightmare to complete and I love my hedge. I'm hoping you're all going to say we're in for the coldest winter in decades and they'll all die. 

Please help