Winds wildest in 40 years, foresters say
Up to a million tonnes of wood might be on the ground across Canterbury after historic storms two weeks ago.
Winds of up to 200kmh were recorded at the top of Mt Hutt at the height of the blast, the likes of which foresters say had not been seen for 40 years.
Parts of McLeans Island recreational reserve, popular with mountain bikers, will be closed for months due to "fallen and dangerous" trees over much of the walking and cycling trails.
An Environment Canterbury (ECan) spokeswoman said they were still assessing some damage, so there was no way to know yet how long the park would be closed for. Some parts were planned to reopen by October 5.
A post on the ECan website informs people there is "a huge amount of work to complete before we can reopen so please stay away for now to allow us to work as quickly as possible".
The McLeans Island Golf Course had also suffered extensive damage, and was closed "until further notice".
Meanwhile, foresters say it will take another few weeks before they know the extent of the damage.
But forestry consultant Allan Laurie said the million-tonne figure was being bandied around.
"The net impact will be significant, but putting into context with 1975, when there was a major blow in Canterbury, we had about 2.5 million tonnes of wood on the ground and the net impact of that was said to have affected Canterbury's log supply for up to 20 years.
"This one is at a lower level, but still significant nonetheless."
The damage spanned the whole of Canterbury, as far north as Amberley and as far south as Oamaru in North Otago, although it was in isolated pockets like Geraldine.
Sawmillers are concerned the damage may have hit younger trees which could create shortages of supply in future years.
However, Laurie said it appeared that trees of all ages were hit.
Darren Mann, general manager of Rayonier's Matariki estates in Canterbury, said the winds did substantial damage in its Eyrewell and Ashley forests in north Christchurch.
The estimates floating around were "pure speculation", he said.
"We've been spending a bit of time just flying those areas and remapping, just building up a picture of what we're dealing with. We'll certainly have crews assigned to salvage for a while."
A small silver lining was that many of Rayonier's fallen trees were quite mature and could be used for processing.
"By and large, the younger part of the estate held up pretty well."
Foresters will be under pressure now to recover the wood before it begins to swell or rot.
Wood younger than 25 years is not acceptable for processing and Ian Anderson, of McVicars Timber Group, said younger wood would be either chipped or exported.
The extra volumes were not expected to affect the export log price.
"It's not so much about the here and now, it's two or three years down the track when those trees will be coming to millable size or millable age, they won't be there."
Laurie said many local sawmillers were starting to struggle to source wood for the domestic market.
However, it remained to be seen whether the windthrown wood was a boon for the Christchurch rebuild.
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