The recent weeks of sunshine are having an interesting side effect on Lancashire’s canals, which are being invaded by a green carpet of weed.

The Canal & River Trust (CRT) has begun the painstaking task of removing millions of pieces of floating duck weed from the water, which multiplies rapidly in the heat, across its waterways. Last week they cleared a mile-long section on the Lancaster Canal, between Hollinshead Fold Bridge and Ashton Basin.

While an individual piece of duck weed is no bigger than a ladybird, congregated together they can resemble a thick carpet across the canal.

This accumulates litter, which can be problematic for the hundreds of boats and leisure craft on the water. Over 70 tonnes of duck weed per week has been collected by CRT teams. They are asking people to get in touch via their website or social media channels with sightings of duck weed. 

Ecologist Diane Rollin explains: "Duck weed is really noticeable across our canals at the moment. It’s been flourishing in the warmer weather and sunshine.

“The weed is not harmful to people, but dogs and other animals have been known to mistake it for grass and ended up in the water. Significantly, if left to thrive, it can cause problems for other aquatic wildlife by starving it of oxygen and sunlight, so please get in touch if you spot areas along your local river or canal that look particularly bad."

She added: "We’re asked what it is all the time. Some people describe it like a garden lawn, pea soup, or even green porridge! The food references are interesting though, as we found that people in South East Asia regularly eat duck weed because it contains lots of protein.

“I see plenty of ducks tucking into it, so I guess it could be the next super food craze. But in all seriousness, hopefully nobody would be foolish enough to eat it from the canals!"

The Trust is also reminding people to take care when out walking with dogs and with their families, and asking people not to throw litter onto the weed.