What do matches, skunk spray, lightning strikes, rotten eggs and farts share in common? You get a gold star if you said sulfur dioxide.
A bright yellow mineral, sulfur (also spelled sulphur) is the fifth most abundant element on Earth and has been used for a variety of purposes, including as an insecticide, since ancient times. It’s now used to make sulfuric acid in the manufacture of fertilizers, batteries and cleaners; to refine oil and process ores.
Sulfur on its own is odourless, but you might recall that it was referred to as brimstone in the Bible, meaning ‘burning stone’ because when burned in air it produces a blue flame and sulfur dioxide, which creates its distinctive odour.
So what’s this little lesson in chemistry got to do with chickens? It turns out that sulfur can be used as a natural remedy to deal with mites. I know there are a number of chemical products that are effective against ectoparasites, but I always try to look out for natural, easily accessible and inexpensive alternatives.
The most common ectoparasite, Northern Fowl Mite, lives on chickens: feeding on their blood causing inflammation, anemia, 10-15% drop in egg production and weight loss. Severe cases can lead to premature death.
Sulfur has been registered in the USA as a pesticide since the 1920s, but more recently it got it’s scientific due when researchers from the University of California, Riverside conducted studies on its efficacy to confirm what many farmers have known for centuries: sulfur is an effective way of eradicating mites. Despite the fact that sulfur has long been used to control mites, the how of it is unknown. The theory is that sulfur dust is converted into hydrogen sulfide by the chicken’s body heat and it’s that compound which works as a fumigant.
Most large commercial poultry production facilities deal with parasites by using high-pressure insecticidal sprays that can penetrate chicken feathers to reach mites, lice, and fleas. Small flock keepers can use feed store products like Ivermectin or Permethrin to treat individual birds topically.
I have had a couple of outbreaks of mites and used a combination of Ivermectin and access to a dust bath. It’s easier to have my birds work at ridding themselves of parasites before they are an issue than for me to attempt to eradicate mites once they’ve become a flock-wide issue. For me, there’s almost nothing worse than being covered in tiny bugs. I’ve spent nights lying awake being tickled by them as they make their way up my arms and across my face in the dark.
Sulfur can be provided to chickens in a dust bath, which often also contains fine dirt, sand, wood ashes and/or diatomaceous earth (DE). By coating their feathers and skin with the ‘dust’ the parasites are often knocked off the bird’s body or suffocated. Sulfur can be added to their dust bath as an effective way of controlling Northern Fowl Mites, even for chickens sharing the same coop that do not use the dust bath.
Researchers Amy Murillo and Bradley Mullens evaluated an alternative technique for using sulfur to control Northern Fowl Mites within chicken housing by providing sulfur in a mesh bag that allowed chickens to treat themselves with the pesticide.
Small gauze bags filled with sulfur dust were placed in locations where chickens were likely to brush up against them, such as above the coop door, nest boxes or near a food dish. Each time a chicken touches the bag small amounts of sulfur drop onto their feathers and into the coop environment.
Sulfur dust bags have proved more effective than permethrin strips. On average, sulfur reduced mite infestations to low levels within one week of treatment and eliminated mites in three weeks. Hanging dust bags worked better than bags affixed to the cage floor because they allowed for greater physical contact. Another bonus is that an increasing number of mite populations are becoming resistant to permethrin, while sulfur is still a novel treatment.
Self-treatment has other advantages: it cuts down on the workload of chicken keepers and reduces stress to birds because they don’t need to be handled. Dust isn’t good for the respiratory systems of both people and birds, so not having dust clouds in the air is better for everyone.
After I read about using sulfur I went out and bought an inexpensive box at my local garden centre. I looked around the house for little nylon bags that hold sachets or tea bags, emptied them out and filled them with powdered sulfur. I then suspended them above the coop entrance and at the top of the nest boxes. I can’t say how effective they were as my flock also has year round access to a several outdoor dust baths. I see sulfur as more more tool in my larger strategy of pest control. I am happy to report though I haven’t had any significant dealings with mites in several years.
Sulfur is available in liquid, granule and powdered form. I would recommend the latter, used sparingly.
Credits: Amy Murillo and Bradley Mullins (Journal of Economic Entomology 2017); Poultry Site; Meredith Swett Walker. Featured photo: Adobe Stock