The ban was introduced in June 2005 in response to the government's climate change plans. These involved nationalising the carbon in those forests eligible to earn carbon credits under Kyoto and imposing a deforestation tax on owners of forests which weren't eligible, if they didn't replace their trees after harvest.

"We are pleased with the government decision, announced in September, to allow owners of Kyoto-eligible forests to be responsible for their own carbon credits and liabilities," NZFOA chief executive David Rhodes says.

"But land owners are still being heavily penalised by a deforestation tax which, at very conservative values, would cost land owners over $11,000 per hectare to convert forests, even after allowing for any allocations of emissions units. The policy will not even allow the owner of a forest on good dairy land to harvest and replant on erosion-prone farmland on, say, the East Coast, without facing this penalty.

"David Rhodes points out that the Kyoto Protocol contains a number of decisions on forestry that are widely acknowledged to be artificial, such as the decision that for forests planted before 1990 all the carbon in the trees will be instantly emitted at harvest and none of the carbon absorbed during the life of the tree will count.

"Policy measures intended to limit deforestation of tropical rainforest should never have been used to shape policy for plantation forests in NZ, many of which were planted on land that was once farmed.

"Whatever the reasons for the government signing the Protocol, there is no justification for bringing this unrealistic distortion into domestic policy," Mr Rhodes says.

"The threat of a deforestation tax is creating real problems for forestry and leaving many landowners with a stranded asset. New Zealand is the only country to propose a landuse change tax, and investor confidence has been badly shaken. The tax restriction would create very different economics for landowners with pre- and post-1990 plantations. This would likely see the owners of pre-1990 forests making decisions that are good for their business, but undesirable for forestry and the economy as a whole. The fact that exemptions are proposed for smaller areas of forest only adds further inequities to what will be a complex and costly regime.

"Mr Rhodes says forest owners have lifted the access ban as a gesture of goodwill, in the hope that the government will decide not to proceed further with the deforestation restrictions.

"Avoiding a deforestation tax does not mean we want to chop all our forests down. The reverse is true — we welcome measures to increase forest plantings," Mr Rhodes says.

"History shows that the vast majority of forests will be replanted after harvest. A few plantations are — for historic reasons — now ‘in the wrong place ’ , although under the current frenetic rate of cutting to avoid the tax many of these will be gone by 2008. In the same way, there is about 1 million hectares of erosion-prone farmland that should be in trees.

"Deforestation has historically been so low as to not be worth recording. The temporary issue of loss of plantation forests has been aggravated by the government choosing to shelter the agricultural sector from the true cost of its greenhouse gas emissions, such as nitrogen.

"Farmers have tools available right now to limit emissions of nitrogen to both air and water. The argument that there is nothing that farmers can do just isn't true.

Mr Rhodes says the government has provided a signal to the agricultural sector that things are going to change in the future, but only slowly, and in the meantime the encouragement of farming over forestry will remain.