The Dutch Plant Health Association has confirmed the presence of beetle larvae in public areas of Boskoop, leading to the implementation of a 2km quarantine zone that effectively prevents 550 nurseries from selling plants.

The Royal Dutch Wholesalers Association for Flowerbulbs & Nursery Stock (ANTHOS) -- the Dutch equivalent of the HTA -- is working with growers to eliminate the problem.

Secretary Matthys Mesken said: "What the damage will be is difficult to say. Hopefully they won't find any more beetles because if they will do it will be a big disaster. As well as the economic cost, it has damaged our image, but what that cost is will be hard to say."

Growers are required to foot the bill for the inspections, which Mesken estimated could cost in excess of EUR150,000 (£131,301) and may take up to a month to complete. There is no compensation available to them and the cost of lost sales could end up being considerably more.

But UK growers may be able to step in as retailers unable to acquire Dutch plants look for replacement stock.

Nursery consultant John Adlam said: "This is a difficult time for Dutch growers and maybe for UK growers who had orders placed from that area. If garden centres have orders from Dutch suppliers they may need to look into purchasing from UK suppliers. It's an opportunity for UK growers to meet the needs of other nurseries and garden centres."

News of the outbreak emerged during the IPM Essen show in Germany, where hundreds of growers nervously traded gossip.

Johnsons of Whixley joint managing director Andrew Richardson said: "Everybody who came on the stand had a comment about it. In Holland it's such a big story that it is all over their news - it's really serious for them.

"But it might be an opportunity for UK growers. They had a problem with it 18 months ago and one way or another it has not been sorted. Consumers need to know there is a huge benefit to UK stock."

The European Nursery Association discussed the outbreak at a meeting during the show. Chairman and Belgian grower Willy De Nolf told HW: "The Dutch growers were obviously concerned but we are confident the situation will be under control again soon. Last week no plants were exported from Boskoop and clearly that is a very strange situation."

According to ANTHOS, nurseries in the quarantine zone are banned from selling plants until they have been inspected.

Mesken added: "Once they have been inspected they will get a certificate and then they can sell again. Inspections started on Thursday (28 January) and they will continue for about three to four weeks." A list of inspected firms can be found online at www.naktuinbouw.nl.

While the Dutch looked to play down the impact of the outbreak, HTA business development director Tim Briercliffe said its location made it significant: "This has not happened before in such a key area. If it had been a month later it would have been even worse. Because it is in Boskoop, hundreds of nurseries are affected - in the UK it would only have been one.

"There has been a significant decrease in the imports from Holland in the past year because of the exchange rate, with more inter-trading between UK nurseries - that's a good thing because it keeps out pests such as this."

Many British growers were scrambling to asses the impact of the outbreak following emails from the HTA warning them to be vigilant for any sign of the beetles.

Wyevale Container Plants managing director Andy Johnson said there might be concern for young plant supplies but some growers could see small gains as a result.

Meanwhile, retailers warned that the pest could further disrupt trading as they look to get back on track after the chaotic start to the year caused by the extreme weather.

Buckingham Nurseries & Garden Centre planteria manager Chris Day said: "This could impact all importation at a time of the year when garden centres start their spring re-stocking schedule."

Food and Environment Research Agency (FERA) international plant health policy team member Steve Ashby said FERA inspectors were looking out for the pest, given the numbers found in Holland.

He added: "We can't rule it out being here. The two big threats are Acer and bonsai. These are coming in from the Far East and we are encouraging the EU to take stronger action to stop it."

Inspectors found the beetle on Acer consignments in 2004 and eradicated it. In 2008, "quite large numbers" formed another UK outbreak.

Ashby said: "The beetle could be a big problem if it moves into native trees. In Holland they have had findings in established trees - ours have just been in imports."

Adlam added: "It burrows into the stem and smaller trees will snap off at that point. It's something we don't want to see established in the UK."

The common plants affected include apple, peach, birch, elm, maple, poplar, plum, cherry, willow. The beetle can also live in pallets. Foliar insecticides bifenthrin and chlorpyrifos are recommend to tackle the pest.

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