Empowering the Next Generation to Face the Problem of Invasive Jumping Worms

As educators and mentors, we teach children that earthworms are a friendly garden helper that aerates the soil and help plants grow. But right now, our northern ecosystems are facing a silent underground invader that requires us to talk about a not-so-friendly species, jumping worms.

Jumping worms, originally brought here through horticulture, have been slowly adapting to local climates, surviving winters as tiny cocoons beneath the soil, and being quietly moved around in shared plants and mulch. This is called a lag phase.

Once an invasive species reaches a critical mass -- and gets a boost from environmental changes like warmer winter -- this quiet lag phase ends.

Jumping worms are now moving north and are a new invasive species in Canada, while the harm they are now doing to forests in the United States is formidable. 

Larger industries like commercial construction, landscaping and topsoil transport are their major vectors and will soon face stricter regulations. However, at this moment in time, although Canadian children are certainly not a significant vector for spreading this species, they can become soil stewardship aware and in doing so, better protect their local parks, gardens and forests now and in the future, armed with practical knowledge before the species arrives. By teaching good garden protocols and citizen science, we transform eco-anxiety into direct, community-driven action.

Because jumping worms were in a lag period for so long, government policy and official regulations are moving too slowly to contain them. For this reason, citizen awareness is essential. We cannot wait for top-down restrictions when we know protection starts in our own backyards, parks, gardens, and summer camps.

Jumping Worms do not benefit the soil.

• They destroy soil structure: Jumping worms voraciously consume the organic leaf litter layer at the top of the soil, stripping it of nutrients and leaving behind a coarse, dry texture that resembles dry coffee grounds. This degraded soil cannot hold moisture, erodes rapidly, and fails to support native plant or seedling life.

• They threaten entire forests: By ruining the soil bed, they harm the regeneration in our forests, destroying habitats for birds, insects, and native wildflowers, while engineering a disturbed soil where hardy invasive plant species thrive.

• High reproductive numbers: They reproduce parthenogenetically (meaning they don't need a mate), and just one 1-3 mm cocoon moved on a boot or a plant root can start an entirely new population.

• They have strong survival defences: North American robins, toads, salamanders and snakes cannot possibly reduce the very high numbers that jumping worms produce annually. Although they die off with the cold, they leave behind many dozens of cocoons in the soil that overwinter and hatch in the spring. These cocoons are incredibly resilient to chemical treatment and controlled burns simply do not affect them, as soil is extremely insulating even a few inches down. In fact, the decaying matter that results in chemical treatment and after a burn can create a population boom, as the hatchlings find the precise sort of disturbed landscape in which they thrive. While some North American wildlife will eat them, jumping worms have defensive features such as moving quickly like a snake, breaking off the end of their tails, and thrashing when caught, while tending to concentrate heavy metals in their bodies, making them fairly unpalatable past the juvenile stage.

The Mustard Pour Test

If you suspect an area in your camp, schoolyard, or local park has been compromised, you can perform a simple diagnostic check called the Mustard Pour. Remember, there are many soil-dwelling species that create slight on-surface disturbances potentially mistaken for the early stages of a jumping worm problem. Be careful not to pour into an area where a native species has set up shop. Jumping worms are at places where humans have accidently put them there and particularly where decaying vegetation is plentiful. Many other worm species look a bit like a jumping worms, so learning identifications skills is a process.

 Important Safety Note: The liquid must be mixed and poured entirely by older children and with an adult leader. It is a kitchen spice diluted in water but is also an irritant. Younger kids should be strictly in the "observer and reporter" role and should protect their eyes and skin from contact with a mustard pour.

The Recipe & Method

• 1 Gallon (approx. 3.8 Litres) of Water

• 1/3 Cup of Yellow Mustard Powder (the dry spice ground mustard)

If you want to make a slightly smaller batch:

• For half a litre (500 ml) of water, that is around 3 1/2 tablespoons of dry mustard.

Mix the mustard powder thoroughly into the water. Find the suspect patch of soil, clear the surface leaves, and slowly pour the mixture over the ground. The mustard acts as a safe, temporary skin irritant to the worms, forcing them to rapidly surface.

If they surface, look for distinguishing features: a smooth, milky-white band (clitellum) that completely wraps around their body nearer the head than the middle (at the 14th segment), and a violent, snake-like thrashing or "jumping" movement when touched or handled.