ONCE hit by health and safety concerns, the traditional autumnal game of conkers looks set to fall victim to foreign invaders.

Horsechestnut collectors are being warned they face returning home emptyhanded or with under-sized conkers, too small to play the playground pastime, after unusually high rainfall caused health problems for the trees.

Forestry Commission researchers said that while a rise in moulds, fungi and mildews had made many trees less productive than usual, horsechestnut trees were being affected by a new invader – a tiny Macedonian moth called the horsechestnut leaf miner, whose larvae tunnel through the leaves to feed, causing the leaves to turn brown in mid-summer.

Dr Barnaby Smith, of the Natural Environment Research Council, said the leaf miner moth had arrived in Yorkshire last year and was believed to have reached the Scottish borders this year. He said: “The only thing to have moved across Britain faster is the harlequin ladybird.”

A Forestry Commission spokesman said repeated leaf miner and fungal leaf blotch attacks, combined with wet weather or another bacterial infection called bleeding canker, could cause horsechestnuts to go into decline.

Yoredale Natural History Society secretary Leonard Shepherd, of Leyburn, North Yorkshire, said he had received reports of horsechestnut trees bearing fewer and smaller conkers.

He said: “It’s wrong to say there are no conkers anywhere because there are little pockets that have had good weather.”

Weeks after the Health and Safety Commission stated children needed greater freedom to play games such as conkers, fans of the game across the North-East and North Yorkshire said it was unlikely they would be able to play this season.

Keith Flett, of the Campaign for Real Conkers, said by this month he was usually informed about numerous competitions in the North of England, but had heard of none this year.

He said: “It doesn’t look good. It is possibly the worst year for decades for collecting and playing.”

Trimdon Colliery’s annual conkers contest organiser, Derek Langley, said he had seen few conkers on trees in the area while Geeta Bannister, of the Bardon Mill and Roman Empire Conker Championship, said she was working on a backup plan for her event on October 20, following reports of few suitable conkers.

She said: “We are not giving up yet. We might have to import them from down South for the championships.”

Dave Brown, who organised the inaugural North-East Conker Championships last year at Teesside Retail Park, said it appeared some of the Cleveland area remained unaffected by the horsechestnut tree blight.

He said: “We’ve decided not to hold it this year, it takes quite a lot of organising, but hope to hold a championships again next year.