Meet a talented trio of highly specialised detection dogs, who focus on UK’s most invasive plant, the notoriously tough-to-erradicate Japanese knotweed.

Nica the springer spaniel, Nettle the working cocker spaniel and Phoenix the Dutch shepherd devote their entire working lives and considerable skill to finding Japanese Knotweed.

Everything is a training opportunity for Kat, here with her dogs (L-R Phoenix the Dutch shepherd, Nica the springer spaniel, Nettle the working cocker spaniel and rescue Leathe, in training to join the team).

Together with their talented handler, Kat Janczur of Canine Detection Solutions, they work with knotweed eradication companies, landowners and developers to survey construction sites, highways, railroads and individual properties. 

Kat wears organge hi vis jacket and bright yellow trousers. Phoenix the Dutch sheperd dog holds his toy,
Phoenix the Dutch sheperd holds his favourite toy – his reward for good search technique at a typically muddy construction site.

Japanese Knotweed is the UK’s most invasive plant.  Over two metres high in full bloom, it has evolved to withstand volcanic eruptions and seismic events, and can lie dormant for years, waiting to regerminate once conditions are favourable.  It’s a very, very tough plant, which means that it’s almost impossible to eradicate, and a constant fight to keep it down.

Nica, Nettle and Phoenix can detect even tiny bits of knotweed, as well as the underground rhizomes, which humans cannot see. This makes them a highly effective surveyors who, as long as it’s not sub-zero temperatures, can check sites, all year round.

A woman's hand with red painted nails holds a small, curling piece of Japanese knotweed no more than four inches long while a dog looks on.
A shrivelled piece of knotweed like this is easily overlooked by humans, but would spring back to life in the right conditions

Kat explains to Dogs with Jobs presenter Kate Fairweather how she keeps the dogs physically fit and mentally at the top of their game for this high stakes detection work. She explains some of the techniques she uses to keep her dogs independent, and to avoid handler bias.

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