Ash dieback: More positive tests in Carmarthenshire
Six more positive samples of a fungus which kills trees have been confirmed in Carmarthenshire.
National Resources Wales (NRW) had been testing for ash dieback in the Ferryside area after an initial case of the disease in mature trees.
NRW has been carrying out a 1.5km (0.9 miles) sweep around the first case and other samples have tested positive.
The first infected trees were discovered last week.
Until now the Chalara dieback in Wales had been confined to newly planted sites in trees from nurseries known to hold infected stock.
But the Ferryside finding marks the first discovery of the disease in the wider environment on the western side of Britain.
NRW had said it would be just a matter of time before the fungus spread to the wider environment.
The disease - caused by the fungus Chalara fraxinea - has also been found in the wider environment in the south east of England and the east side of Scotland since it was first recorded in Britain in early 2012.
Seminars are being held to offer landowners and tree planters advice and guidance about how to deal with the fungal spores which attack young saplings and mature ash trees.
"It's almost been like we've only seen the tip of the iceberg in Europe," said tree pathologist Joan Webber.
"It's an organism that was only really identified in 2006 and there's been a real confusion over whether it is a new organism or whether it's closely related to a native organism."
NRW said the source of the infection in Ferryside was near where young ash trees were planted between December 2006 and March 2007.
The disease poses no risk to human or animal health and public access to woodlands is not restricted.
However, people are asked to behave responsibly and take simple precautions such as removing mud from footwear and tyres.
Ash dieback is spread by airborne spores and can also be moved long distances by the transport of infected material.
Anyone who thinks they may have seen trees with symptoms of dieback are asked to let NRW know by using the free Tree Alert app or online form available at www.forestry.gov.uk/treealert.