THE value of windblown Scots pine will "quickly deteriorate" unless it can be felled "as soon as possible". 

That's according to industry figures who estimate around 20 per cent of Scotland's annual timber harvest was torn down when Storm Arwen wreaked havoc across the country last month. 

High winds - reaching speeds of up to 100 mph - blew down trees, blocked trails and roads, and caused extensive damage, particularly in Aberdeenshire and Dumfriesshire. 

Andy Leitch, deputy chief executive of Confor, which represents the forestry and wood-using industry, told BBC's Farming Today: "We reckon through our guestimates at the moment, and that's just through our members feeding back to us, we have lost between 1 and 1.5 million cubic metres. 

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"However, we will know much more when we have done an analysis of satellite imagery.

"If it's 1.5m cubic metres, that equates to 20 per cent of the harvest we fell annually in this country.

"The impact that will have is it means the landowners will have to sell a lot more timber than what was planned. So, the industry will have to get together, along with the public sector, to ensure we can get this material felled quickly and safely. 

Forestry Journal: Andy Leitch was speaking on the BBC Andy Leitch was speaking on the BBC

"Otherwise it will deteriorate and we will lose a fair bit of that wood." 

When asked how long the industry has to remove the windblown trees, Andy replied: "It depends what state the trees are in. 

"There are quite a lot of snapped trees. That means the crop will deteriorate quicker. 

"Scots pine, for example, we have to get in there as soon as possible. It deteriorates very quickly once it is felled or comes off the root.

"That becomes very low value within six months, so we need to get in there quickly. 

"The pine and other species hit hard looks like sitka spruce. If it's been snapped, we have between six months and a year. If it's on the stump, we have just over a year. 

"But we do need to get in quite quickly. 

READ MORE: Storm Arwen: Confor's initial estimates suggest 20 per cent of Scotland's timber trade damaged by winds

"Windblow is a very dangerous operation. The best way to harvest it is by harvesting not just the windblown trees but the ones standing as well. Otherwise they will just fall down." 

While the damage is estimated not to be severe enough to instigate the Scottish Windblow Action Commitee (SWAC), Andy warned harvesting costs will still rise given the scale of the operation. 

"It will cost more to harvest the material and we will lose a percentage of it because a lot of it will be snapped," he said.