Moth flies

My house has been taken over by small critters that look like a cross between a moth and a fly. I initially thought they originated in the bathroom, as I always seem to see one while I’m taking a shower (I was beginning to think it was the same one — just a stray who’d wandered in and found the bathroom hospitable enough to stay), but I opened the worm bin the other day to discover a teeming horde of them dining contentedly on something or other in there.

While piddling around on Vancouver’s incomparable City Farmer site (add that one to my list of nonprofits that will be getting a little something in their Christmas stocking this year — I owe my worm bin and my excellent dog waste composter to these folks), I learned that the aptly named moth fly is a common interloper in compost bins. There was no photo, but a Google image search confirmed that my houseguests are, in fact, moth flies — also known as drain flies because of their propensity for dining on the muck that collects in household drains.

They’re neither a moth nor a fly, but they’re harmless (if a wee bit annoying). It appears that they originated in the bathroom and then discovered the delectable smorgasbord in the worm bin and decided to throw a party in there.

Click here to see what they look like.

I think they’re sort of cute, although I will probably follow City Farmer’s advice and toss some baking soda and cover material into the worm bin to discourage them from breeding in there any more. I don’t think my worms should have to share their food with strangers. The flies can grab a snack in the drain. My worms have no such options.

Speaking of compost, the aforementioned dog waste composter is still going strong. As you’ll recall, Ron installed it in mid-January. Nearly 10 months later, it’s not even half-full. I swear, if I weren’t so madly in love with Route 66, I’d run away to Vancouver just so I could hang out with the City Farmer crew. I’ve got to get up there for a vacation one of these years. I am dying to tour the demonstration garden.


3 thoughts on “Moth flies”

  1. Hi there. I also have an infestation of moth flies. Generally I don’t mind insects and they usually die off by winter anyway, but these moth flies were actually beginning to gross me out a little. So I’m going to go try your baking soda trick. Did it work for you? It doesn’t hurt the worms to alkalize their home? I haven’t been feeding them for weeks cause I didn’t want to encourage their guests- poor little guys. Anyway- thanks for the blog. Good luck with the moth flies.

  2. The baking soda didn’t seem to hurt the worms. I can’t tell it made a lot of difference with the moth flies, but I reduced the infestation in my home by switching to a different container with a tighter-fitting lid. What I’d been using was one of those plastic three-drawer storage cabinets, with holes drilled in the sides and bottoms of the drawers for aeration. It was handy to be able to open the drawer and toss in my biodegradables, and I liked being able to quarantine some of the worms while I tried new food, bedding, etc., but the gnats and moth flies had WAY too easy access in and out. I felt pretty confident that I had a good balance of food, bedding, and water, so I went ahead and put all the worms and all their materials into a plastic tub with holes drilled in the sides and a tight-fitting lid on top. The bug problems have decreased dramatically since then. I highly recommend this approach if you haven’t tried it already.

  3. I don´t get it. How can you eliminete moth flies in the worm bin just by putting a tight-fitting lid on top when the flies are already there and can procreate there on and on? I also have a moth fly infestation so if you got rid of them, please explain. Thank you

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s