In my last post, I might have mentioned the issues I’ve been having recently with fungus gnats or sciarid flies. As the yellow sticky traps have become covered with them, I thought I’d try making my own sticky traps to see whether they worked. I roughly followed the instructions here: https://www.thespruce.com/how-to-make-fly-paper-1389064, substituting golden syrup for the corn syrup.
I only wanted to make a little – just to see if it worked – so I mixed 2 tablespoons each of water, sugar and golden syrup in a pan and heated it until the sugar dissolved.
I found some paper I received as packaging and cut that into strips. It was brown paper on one side and green on the other. I punched a hole at the top of the paper and put a twist tie through it. Then I dipped the paper in to the mixture, brushing and getting it to soak in. I strongly recommend that you have an area for hanging these up with something to catch the drips ready before you start – these things are sticky! And a bit messy!
I left the traps to dry overnight in an area where there are a lot of the pesky flies – I was hoping some of them would get stuck straight away, but no.
Once they were dry and had stopped dripping, I hung them in the areas where the yellow traps had been and where there was an infestation of the flies in some of my indoor plants. The traps felt sticky to me, but they were a “light” sticky, and not as heavy feeling as the commercial traps. It’s a bit like the difference between the sticky side of some sellotape and some duct tape – light sticky and heavy sticky.
After a few days….I’m sorry to say that these really weren’t too successful. I even watched a fly land on the paper and after a little wriggle, just walk across the surface of the trap. It did catch a few flies (about 3) but the yellow commercial traps caught dozens in the same time.
If I made these again, I would need to think about making them “heavier” in terms of the stickiness. Looking at the recipe, I think it needs a bit more sugar and for it to be heated to a higher temperature (not just dissolved) so that it can start to form a melted sticky mass – soft-ball in sweet-making terms. I understand that this is around 112-116oC, so could make the whole process more dangerous. Still, could be exciting! I think the golden syrup is there to stop the sugar from crystallising and to aid stickiness. I think I’d also have to source some yellow paper since it seems that it really does attract the flies. The back of my packet of commercial traps from Bayer describes them as “aureolin yellow” so that’s what I’d go for. Looking at the traps I’ve used, most of the flies seem to be around the edges. I’ve no idea why that would be, but maybe narrower strips of trap would work well.
Anyway, the fungus gnat problem isn’t over yet – I’ve started to put the yellow traps directly over the surface of the soil by cutting them into small pieces and balancing around the rim of the pot. I only peeled off the covering paper on one side to make positioning these a bit easier. This has stopped quite a number of them (again around the edges of the trap – how strange!) but I think I will be looking at sourcing a butterwort or a cape sundew once the weather gets warmer, and continuing to spray with neem oil.
Gardening studies 