David Matthews, chairman of the council's rural community board, said Whanganui's rural roads would experience heavy vehicle movements at least four times and possibly 10 times higher than those servicing existing farming operations adjoining the forests.
"For every tonne [of product] per hectare coming off my farm there'll be about 50 tonne per hectare coming off a forestry lot," he said.
He said this presented a clear case for introducing either a special forest road policy or a differential roading rate.
But Mr Martin told the Chronicle that "even with my limited experience in farming", forestry didn't produce 53 times the tonnage per hectare as pastoral farming as some commentators were claiming.
Arbor Forestry manages more than 50 forests across the Whanganui region. Most of those are off State Highway 4 with others in the Turakina Valley and near Mangamahu.
He said many of those owners were encouraged by local government to plant trees in the mid-1990s, not only because returns were high at the time but because forestry was seen as a sustainable land use.
"There were even grants available which encouraged new plantings," Mr Martin said.
"But that same local government is effectively telling these owners that they were happy to pocket their rates every year for the past 30 years, spend it on a failed wastewater treatment plant [among other things], and not bring any of the district roads up to a standard to handle heavy trucks.
"These forests have now been there for over 20 years. Surely someone in local government would have had the foresight to spend some money upgrading these roads before it became a problem."
Mr Martin said a forest sat idle for almost 30 years before any major operations occurred, so a roading network is the only thing a forest directly needs from the district in order to realise returns.
He said what also needed to be remembered was the economic impact that forestry yielded for a region.
"A 200ha block of forestry will produce about 4000 truck-loads of logs over a two- to three-year period, once only in 30 years. Keep in mind a similar-sized dairy farm will have a similar-sized truck pick up milk once a day, virtually every day.
"Over this same two to three-year period about 30 people will be employed full-time to complete the harvest operation. This includes logging crew, in-forest roading crews, supervisors, truck drivers. And that's before you consider the flow-on effects to other businesses such as food and clothing providers, mechanics and accountants."
Mr Martin said during that same short period about $1million would be spent on in-forest infrastructure in a 200ha forest, which includes roads and skid sites. A further $3.6 million would be spent on log transport and about $4.2 million on logging itself. "The forest owner will be unlikely to receive any more than what they spend on logging the forest in net returns."
He said as there were no major local wood processors in Whanganui most wood was trucked from the region using the state highway network, which was not the responsibility of the district council.
"The rail yard at Eastown may only account for 40 per cent of volume from a forest but I would guess that having that yard actually decreases the impact on district roads as wood is transferred to the rail system, which again, the district doesn't pay for."
Mr Martin said he could understand farmers' concerns about the potential for damage but it was a concern shared by a number of Arbor's clients who access their forests on those same roads.
"However the blame should be laid squarely at the feet of the district council, not the forest owners who have no choice in how their rate money is spent. Increasing rates will do nothing but discourage investment in forestry within the region."
He said forestry contributed more to the local economy than people realised.
"We don't get recognition in the media because we don't have a united lobbyist such as Federated Farmers to go into bat for us. Most of the time forestry is perceived negatively by the public because there is little pushback from industry stakeholders when these issues are brought to light."
