Manure containing the previously-banned aminopyralid herbicide has been found in gardens and allotments despite being reinstated under tighter controls.

Aminopyralid was reintroduced in April with sales restricted to Scotland, the South West and Northern Ireland to address issues with contamination.

It was voluntarily suspended by Dow AgroSciences in 2008 after sensitive crops on some gardens and allotments were affected by manure containing traces of the herbicide.

Andy Bailey, Dow AgroScinces principal biologist, said the discovery was disappointing, but said the contaminated manure was not from the current season.

“It is a reflection of manure generated from past treatment and kept in heaps for more than a year,” he said.

The updated restrictions in aminopyralid use means manure returns immediately to pasture so it does not leave the farm and risk causing harm.

The herbicide can not be used on grassland destined for hay and silage, or on grassland grazed by horses.

Mr Bailey said concerned farmers or gardeners should check the source of their manure where it is being used on sensitive crops.

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