There are maggots growing in my garbage dump, and you tell me it's a good thing?

Full text insect terror warning!

On a rainy morning in September, Ms. Da, who lives in Shanghai, opened the compost bin on her balcony and was shocked by a layer of oval, wriggling, two-centimeter-long yellow, paste-like organisms inside.

The horrified Ms. Da then did what a horror movie character usually does: she closed the box and walked away as if nothing had happened.

I didn’t take a picture at the time, this was taken later | Photo provided by the author

Two days later, a line of yellowish creatures poked out from the cracks in the lid, stretched out half of their bodies and twisted slowly, just like the lady who covered herself with the quilt up to her belly button in the summer but hung her upper body outside the bed to enjoy the air conditioning. When the lady touched the compost bin, she found that it was getting warmer ...

Feeling warm, Ms. Da then did what a documentary character usually does—she opened a museum group and typed:

"My compost seems to have maggots. Can I send pictures to this group?"

Group member A: "This is a museum group, it's ok, just post it."

Group member A: "But wait, let me go for 5 minutes"

Ms. Da (after leaving enough 5 minutes to escape) posted a picture, and the warriors who stayed behind said that this was not maggots (the common name for fly larvae), but the larvae of soldier flies (which belong to the same order as flies, Diptera).

Group member A: Soldier flies! Soldier flies are so cute!!

Group member B: Didn’t you leave?

Group member A: I was attracted back by soldier flies! Dada, take good care of them, they will be so beautiful after they emerge!

Me: Wanla, I just poured two pounds of coffee grounds in there, I wonder if they will make the maggots dance like crazy

(Conclusion: No. Alas!)

A food waste treatment expert grows out of a compost bin

You may find this a little comforting (or even more confusing), so let me give you some context.

Simply put, I use a foam box to make a sandwich compost of kitchen waste + soil on the outdoor balcony, relying on microbial fermentation to degrade kitchen waste (if you start to worry about the smell, this method has no odor). The compost box will experience several temperature increases under the action of microorganisms, and after months of bacteria and fungi eating each other, it will become decomposed soil with a fresh earthy fragrance, which can be mixed with garden soil to plant plants.

Infrared imaging of warming compost soil | Photo provided by the author

I have been doing this for a long time, and the compost bin has only produced red, orange, yellow and green fungi, and has never grown anything visible to the naked eye . The typhoon a while ago may have caused a crack in the foam bin, and a stray soldier fly discovered this warm, humid and dark treasure land, and left a whole generation of well-developed babies here - I roughly checked the breeding guide, and judging from their size, they are growing very strong.

Soldier flies are organisms of the family Schizophoridae in the order Diptera of the class Insecta. Many species in this family have larvae that are scavengers. The one that appeared in my compost bin should be the black soldier fly ( Hermetia illucens ), a well-known scavenger insect with high economic value - the black soldier fly is an expert in processing kitchen waste . These kitchen wastes rotate at high speed into the body of the soldier fly and are converted into protein by it. Many places such as Guangdong and Hubei have raised black soldier flies to process biological waste. The white and fat black soldier flies can later become protein feed for poultry and livestock. I have long heard of this economic insect, but I have never seen it outdoors - the reason is easy to imagine, and the place where it likes to grow is obviously not where we like to go.

Vanke Center Black Soldier Fly Station, black soldier fly larvae are processing kitchen waste | Guokr

With the help of experts, composting efficiency has improved

Now there are baby soldier flies on the balcony. Ms. Da was very excited when she learned the truth, thinking that her composting skills have been recognized by experts. After consuming kitchen waste, soldier flies produce loose and odorless metabolites, which are very good compost materials, and their metabolism rate is much faster than that of microorganisms : after just over ten days, fresh grapefruit peels are only a pile of ribs, while grapefruit peels in anaerobic microbial composting barrels can last up to a year.

The remaining problem is to deal with another common large mammal in the area: Dada's companion, humans.

That day, when Mr. Hammer got off work, Ms. Da wrung her hands and said carefully, "Honey, I want to tell you something, don't be in a hurry... I raise... a lot of soldier flies outside... But listen to my explanation, although they look like maggots, they are really not maggots, they are very good!"

Mr. Hammer: Oh, it's okay. It's not like we haven't snorkeled in a sea of ​​maggots before. (lost in memory)... the big rats can't be driven away... there's a layer of maggots surging below... the competition among the decomposers is really fierce...

(Inner thoughts: Great! My husband should find someone who has been a forensic doctor and can easily handle a small scene like composting.)

Da (happy): Then do you want to go out with me to see it?

Hammer (shrinks): ...I'm not going!

The life of a black soldier fly | extension.entm.purdue.edu

The Nature Observation Team has added another member

Whether raising plants, animals or even fungi, much of the pleasure lies in observing the interactions of organisms without interference .

In the past compost, I could see corn cobs growing delicate little mushrooms in every cell, just like in modern factories. Penicillium infects corn cobs and defeats mushrooms, and the empire of Penicillium is often quickly devoured by black mold. The finished compost is put into flower pots, and the rich microorganisms attract fruit flies to swim in this huge nutrient pool. The lurking spiders peek at the slow crawling of fruit flies under the shade of plants. In their eyes, this is probably a candy jungle flowing with milk and honey.

There are no pictures of corncob mushrooms here.

Because the author thinks it is unhygienic to stick a cell phone camera into a cloud of fungal spores

Now, this little ecosystem has been joined by soldier fly larvae, which occasionally squeak out half their bodies from the cracks in the lid - it looks like the box is sticking out its (very small) tongue.

I am also a person who has a treasure chest monster at home｜Photo provided by the author

This brought an unexpected blow to my planting business: the soldier flies that swarmed out of the compost bin attracted birds to the farm . The sparrows gathered around the compost bin, plucked one out with a chuckle, and happily jumped away in front of our shocked eyes. In the process, they also noticed the fig tree that I raised with compost, and harvested it accurately, never touching it when it was not ripe, and leaving no peel when it was ripe. By the way, they pulled out a basil and stepped on it, pecked a hole in a tomato, and then took two branches from the insect house that they liked and took them back to make a nest (the rest were scattered all over the ground). What kind of quality.

It was not ripe last night, but it is like this this morning. | Photo provided by the author

Friend: Do you want to put a bag around your plants to protect them?

Me: No, there aren’t many places for birds to play in the city, just like the park is filled with running children and parents setting up tents on a sunny day - who isn’t a middle-aged office worker who is looking for free entertainment space while foraging for food to support his family?

My pleasure is to play with these crickets behind my friends｜Photo provided by the author

A month later, Ms. Da saw an insect as black as night fog outside the compost bin. Its wings were as light as soap bubbles, its body was as strong as a beast, and its iris compound eyes were painted with magical patterns. It was obviously a dipteran ghost. It rested in the morning light for a long time until the dew on its forehead turned into pearly sunlight. Then, it suddenly rose up like a flying yo-yo and disappeared beyond the shadows of figs, tomatoes and roses.

Adult black soldier fly | Photo provided by the author

Author: Dadazi and Hammer

Edited by: Yellowtail Pollock

Title image source: provided by the author

This article comes from GuokrNature (ID: GuokrNature)