If you know this old lady, kindly mention that we have some flies for her. We have over two hundred goats, all of whom defecate. House flies are keen to feed on warm, rotting organic matter such as goat manure, and apparently a pair of flies can produce over a million new flies in two months. There are sensible precautions. We keep screens on windows and doors, and rubbish bins shut. We collect goat manure and cover it while the heap decomposes into valuable garden mulch. However, there are thousands of flies to suppress, and we have a multipronged attack plan. You might have noticed plastic bags mounted on our outside walls, of dubious appearance. They contain a liquid irresistible but deadly to flies. We have also built bat boxes, in the hope of bat tenants moving onto the farm. Starting at dusk, bats will eat hundreds of flying insects every night, including mosquitoes and flies. It only remains to find the old lady, and we won't let her swallow the horses.