A few days ago, I took some food scraps out to our happily rodent-free compost bin in the back yard. It was a quiet morning, and I heard a soft noise coming, I thought, from the neighbor's yard. Then I realized that noise was emanating from the compost bin. And the compost was bobbing up and down. So I carefully peered in, afraid of what I might find…
And yep, there they were.
Grubs.
I refuse to use the word "maggots" because these were much less disgusting to me; instead of initiating the gag reflex, I simply shouted, "Eww!" See the difference?
They aren't white, but instead are black and brown (from what I could tell, I didn't want to stare at 'em too long!), and look like they have more segmented bodies. Still, their writhing inch-long bodies are pretty gross.
Friends of mine who have a closed compost bin have had the same issue (ours is an open-air bin). We've both been adding greens and browns in with our food scraps (veggies only, no meat products), so we're wondering what gives.
I've done some research but have come up with conflicting information. Most of what I've read seems to indicate that these wriggling inchworms are larvae of the Black Soldier Fly, which is different from the common housefly. From what I've read, Black Soldier Flies specifically are really good at decomposing food scraps and will even take care of pet waste. Some gardening sites say it's not a problem to have them in your pile, in fact it's beneficial; and others say no grub is a good grub, add more browns and move on with your life.
Here's the thing, though: sure, they're keeping our compost pile at a low—very low—level. But in the coming months, we want to use compost on our garden. Will it be usable compost? And will we have enough of it?
In other news, the compost bin is not attracting any neighborhood wildlife, does not smell bad, and is not surrounded by flies. So we're down to just the grub problem. Any tips, tricks, or advice from you fellow composters out there?
And who knew there was so much to learn about fly larvae?
Related Posts:
• Good Question: Maggots in My Compost... Help!
• Good Questions: More on Maggots and Compost
• How to Build a Shipping Pallet Compost Bin
• How to Build a 2-Material Quck & Cheap Compost Bin
• Microbes: Making Better Compost
(Image: Flickr member Joi, licensed under Creative Commons)
Find Your Style: 20 Classic to Contemporary Kitchens to Add to Your Inspiration Board
Beth's Romantic & Retro Residence
Good Food to Share 
The Big Book of Small, Cool Spaces 
Apartment Therapy Presents 
The Eight-Step Home Cure 
Shaw's Original Fir...
How To Make Perfect Bacon in the Oven
How To Cook Tender, Chewy Wheat Berries on the Stovetop
I don't understand why people get so bent out of shape about bugs in their compost. Composting is a process of decomposition carried out by microorganisms (bacteria, fungi, etc.) and macroorganisms ("grubs," worms, even ants.)
If they really are black soldier fly larva, then you've got yourself a boon. There are videos on YouTube of those guys breaking down a whole hamburger (meat, buns and all the fixings) in just over 5 hours, and they only eat dead material, so you shouldn't have to worry about them eating up your garden. A female black soldier fly can lay something like 2000 eggs, they have extremely short lifespans as adults, and they don't carry pathogens like house flies.
With black soldier flies, you should be able to safely compost typical no-no items like meat, dairy, even animal waste.
Based on your description, those probably are black soldier fly larva, and they are a good thing! I've attended several composting classes offered by the OSU extension office in Eugene, and they have nothing but good things to say about them.
The same exact experience just happened to me. Merrily walking down the compost pile and then “what’s that noise” “what is that” “AAHHHH”. I ran in the house devastated I actually went as far to call a local composting expert at a gardening center nearby. He basically said, not a big deal at all. I was relieved, to say the least! He said I could pick them out and give them to someone with chickens, but I decided that would be a little to much for me. I thought it was going to be over run, but there ended up being only a few.
They're not bad, they're just gross.
When we (the Milwaukee Community Compost Network) flipped one of our piles last weekend it was literally CRAWLING with grubs etc and steaming (on an 80+ degree day). It's all part of the process.
Did you think decomposition would be pretty?
They'll go away when the weather cools off.
I'm all for actually wanting to have some compost to use in my garden next spring. At the same time, though, another primary reason for composting is to take items out of the trash stream. Even if these larvae are devouring organic matter and leaving little behind, it's still a huge relief to me that all of the "trash" I'm composting didn't end up in a landfill.
Adding more brown and dry leaves helped reduce the maggots in my compost, I also started separating my coffee grinds which I usually added water to to get them out of my coffee press, the more moisture the larger the grub population I found - if you spread out your compost before you use it the sun and birds will clean it up for you. I am use to them and think they really help break things down faster - I compost 100% of my food scraps so I do not worry about them eating too much!
I've noticed that, by adding some shredded paper (bank statements and whatnot), I've cut down on the bugs in my compost.
Ok, I'm going to err on the side of... nature brought 'em there, so I'm gonna leave 'em there. I'm not too grossed out by them, I just wanted some good compost for my garden. But I do have to agree with Claire T.: they're taking care of food scraps and waste, and keeping it out of a landfill. EPIC green WIN!
I might even start a second, smaller heap to try composting pet waste, which I wouldn't necessarily put on a veggie garden. In which case, I'd want the maggots around all year long. :)
What do they sound like? I'm curious.
Okay, relatedly, I just moved into a house with a pre-existing compost pile (small), and turned it yesterday to reveal...a huge ants' nest. I mean, SWARMS of ants, all scurrying willy nilly, carrying what I think were eggs. If they're beneficial to the compost, I'll leave em alone, but we have a stream of ants coming in the house so if they're not I'm going to have to take measures. Though I don't know what measures to take - I don't want to toxify the compost heap.
Lavender oil is supposed to be a wonderful natural ant repellent...If you don't want to use it on the ants, leave it around the compost pile and in the crack of your doorway to keep them out. Hope that helps!
Me too Tamarind!
I would imagine a slight hum or rustle from the movement?
Why would anyone have a problem with bugs in their compost?! Bring on the bugs!!! I mean, I suppose if they're swarming out of the pile into your house or something, you may want to move your pile further from your house, but otherwise, welcome home little buggies!
I have a closed pile too, and get grubs from time to time. Never worried about them, cause they come and go. But I'm glad to know what they are, now.
As for ants, we used to have a terrible problem with them in the summer, especially when the big ol' fig tree started dropping figs. I started sprinkling diatomaceous earth around the yard for flea control for the dog last year, and we haven't seen an ant since. I've never heard of it being an ant control method, but it seems to have done the trick.
When I first started composting, I only did kitchen scraps and was a little grossed out when one day I noticed a carrot waving at me from the compost pile only to look closer and realize there were what appeared to be hundreds of maggots doing the wave, making the pile heave and roll. Then I started covering the pile with leaves and it got better, however things don't break down as fast.