Xylella puts English oak at risk, says grower

Plant disease Xylella fastidiosa could wipe out the English oak in the same way as ash dieback is killing the UK's ash trees, a leading grower has warned, adding that European plant health rules are to blame.

Oak: inspections for Xylella fastidiosa limited to named hosts on an EU list that does not include Quercus robur
Oak: inspections for Xylella fastidiosa limited to named hosts on an EU list that does not include Quercus robur

Xylella has 300 hosts and has badly damaged crops in Italy and Spain. J&A Growers managing director Jamie Dewhurst, whose Warwick-based nursery grows 13 million trees a year, said in the past the expectation has been that the authorities will keep the UK disease-free. But "now they won't - they will just use what powers they have and ultimately as a trade we are responsible for what we do". He added: "I have major issues using a stable door policy. Surely our environment and heritage is worth throwing a bit of resource at."

Speaking at the HTA York plant health conference last month, which centred on the Xylella plant health threat, Animal & Plant Health Agency chief plant health inspector Ed Birchall said inspections are limited to named hosts on the EU list "because of lack of resource". This does not include Quercus robur (English oak), which is only a named host in America.

Dewhurst said: "The Food & Environment Research Agency's John Elphinstone said at the HTA event how difficult Xylella is to identify, how long it takes to show symptoms and how the bacteria is continuously evolving. I personally call for national measures on Quercus robur because it is an iconic tree for the UK. We are going to lose ash and the other major tree of England is the English oak, and if we're not careful we'll wake up and have Xylella in our oak.

"We need to be taking measures to control Xylella in English oak. At the moment, any Tom, Dick or Harry can buy Quercus robur, potentially with Xylella. It's wrong only reacting to species actually identified in the EU at present. We're just waiting for a Chalara situation to happen again.

"I was on the fateful trip (to Holland in 2009 with the HTA after which they warned of the Chalara threat) with Steve Ashworth and the trade and authorities were caught with their pants down (when Chalara hit the UK in 2012).

"The potential for Xylella will blow Chalara totally out of the water - it is the unknown. We've seen it establish itself in France in a very short period of time, and maybe it's already in the UK. I would be very surprised if it is not more prevalent than it is at the moment.

"Trade works on a European basis. I'm European Forest Nursery Association representative for the HTA and members surveyed found 20 million plants are moving within the EU every day of the six-month planting season, and every single one of those is at risk. We need to take control of our borders, not for immigration but from a plant health point of view.

"It annoys me. I know the UK has been accused of taking action for commercial rather than plant health purposes. I was told it this week by a Dutchman that we're keen on using home-grown and you will do whatever possible to protect your own market. Of course we will. I don't believe we've taken action for commercial purposes, we've always done it for the right reasons.

Dewhurst added: "In the UK we have a natural border, the Channel, which gives us an advantage from a plant health point of view. We should take advantage of it. We need the ability to react quicker to outbreaks. Brussels works so slowly to get national measures in place - diseases don't. Emerald ash borer and bronze birch borer are threats and we need to take control of our borders. One way could possibly be by coming out of the EU.

"Dutch growers are very concerned about UK growers pulling out, but I think trade will still continue anyway. Norway and Switzerland have trading relations with the EU so why can't we? We need to take a bit of control back. Chalara had one host-ash. Xylella has 300-plus, so if it moved into the UK it could hit English oak, wild cherry, sycamore. It's a rolling stone, so let's do all we can to keep it out. I don't think present legislation is good enough to keep it out and by the time the new 2019 regulations come in it may be here."

Threat: Nursery industry eager to defend against plant disease

Wyevale Nurseries director Steve Ashworth said: "We are all very concerned and want to get it right in the nursery industry and not get caught out by the new threats. There’s certainly a lot going on with the new [plant passport] regulations coming in autumn 2016 to be fully implemented in three years’ time. It’s quite a big thing to take on.

"I’m reassured by Defra chief plant health officer Nicola Spence looking after things on our behalf. She seems very capable and communicative, and able and willing to talk to us nurserymen. With Xylella, this month prunus was added to the list of items we must report any importation of. Xylella does appear very possibly to be a concerning threat and no one is quite sure of its spread.

"My concern is the cost of all this, though I received some assurance from the Animal & Plant Health Agency. Number one is to keep the disease out but the cost of extra inspections at £145 an hour could escalate. Plant health inspectors wonder how much time and manpower will have to be spent rolling out these inspections. I’d like some guidance from on high that growers won’t be bankrolling onerous inspections. At the event [chief plant health inspector] Ed Birchall suggested they could be tacked into exiting visits and might not cost much more. I’d like to hold him to that.

"Also, extra inspections should be consistent throughout the EU. We want their assurance of diligence. On their part they are insisting other EU states are equally diligent.

Crowders owner Robert Crowder said he is "delighted" that the Government and the industry have got together ahead of any Xylella issue, but he said his concerns are about funding and quality of inspectors as the Government "extended the range of plant passports to cover landscapers, distance sellers and a new range of threats".

Crowder added that he is worried about "the resource of people to inspect all these new sellers and the difference in quality of the inspection teams across the country".

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