The best fly trap bait!

We reuse the tops from the bag style fly traps on old canning jars and we have tried many fillers to attract flies. By far the most effective has been thin slices of potato in water. It can develop a healthy smell if not changed often but I can feed the contents to my chickens without worrying about making them sick!

I thought flies chose sugar most of the time.

Kai Walker wrote:I thought flies chose sugar most of the time.

I think the smell is geared toward where they lay their larvae. A rotten smell.

I use fly jars. I've caught thousands. The scent traps have a rotten egg smell. In fact, i think egg are the main ingredient

Bad pic but shows the quantity.

I used lemon juice and dawn dish soap as my main ingredients, and it worked fine.

I believe what attracts them is smell of the yeast from the potato water (old school bread makers used potato starter). You can also use a little flour like you are making a sourdough starter, but it takes a bit for the yeast to build up, so I prefer the potato.