Yesterday I treated the entire apartment, well that was an overstatement, I treated all the flower pots, orchid pots and vivariums at least with nematodes. Waging war on the Sciaridae. I have not really seen any of them around the apartment, but they absolutely love my nano-vivarium and my flaskbaby nurseries (mini-greenhouses) where it is nice and warm and humid. But I took no chances and treated everything with the tiny biological predators, the nematodes (from Lindesro). It is not as disgusting as it sound, you have larger creatures living in your bed or favorite pillow… namely bedbugs. Anyway, they are harmless to humans and pets and it is nice not having to use any toxic poisons to combat these darn things that have invaded my 35×100 cm slice of tropical heaven (the nano)!
Most people think all the tiny flies we often see around our plants are the common fruit fly (Drosophila melanogaster), and of course – some are. These are however merely a nuisance but harmless to our plants. But there is another pest from the Sciaridae family called Sciara hemerobioides, or the dark-winged fungus gnat (or “sorgmyggor”/”sorrow mosquitoes” as we call them in Swedish – very appropriate name). These evil doers look a lot like the common fruit fly, but are not only a nuisance their larva love to munch on fine tender roots. Although most orchid roots are too thick to be bothered, these larvae can completely decimate a cultivation of fine moss or young plants – such as my tropical moss and flask babies.
You can tell the flies apart (without putting them under the microscope) by the way they fly. The evil fly is not a very skilled flyer, Sciaridae moves in a jerky fashion and is often seen running over the surface rather than flying. They are also not attracted to fruit or wine like the harmless fruit fly so you cannot trap them in this way. They are however attracted to yellow, so I hung yellow fly traps (the yellow cards with glue on them) to catch the adults, then sent in the nematodes (Entonem /Steinernema feltiae) to kill the next generation larvae.
It all took about 2 hours using the high-pressure watering hose (at low pressure) but it is well worth if it only works. Now I just have to sit back and wait. They say it may take 2-3 weeks before you see a noticeable difference, but since I ordered large yellow fly traps at the same time it already feels better. Now I only see one or two flying around in the nano-viv and 50+ stuck on the yellow card – nice! Too bad that they already managed to consume about half of the nice tropical moss I had growing on the EpiWeb back wall… but it will grow back.
My fingers and toes are crossed, and I am prepared to take on round 2 if needed. This is war!!
(Lovely fly images courtesy of Wikipedia)