The organisation representing the forestry industry says the Emissions Trading Scheme should be scrapped in favour of a carbon tax.
The Forestry Institute says while its members have to be part of the scheme, farmers do not, and this has skewed things in their favour.
The institute's president, James Treadwell, said there are other ways in which farmers are - in effect - subsidised compared to foresters, who get no help.
"For instance there is irrigation which happens for farming which obviously helps them, there's a lot of other unintended subsidies that seem to help the farmers in capital gain and they can pay more for land than we can, now we don't want subsidies, we definitely don't want subsidies, but we do want a free and open market."
Mr Treadwell said 700 foresters left the scheme in 2013 alone.
He said the legislation was changed again before the Budget and a lot of people were trying to leave the scheme because of uncertainty, and forestry needed certainty in terms of legislation because it was a 30-year investment.
Foresters argue that new planting is a key part of bringing down emissions.
Ministry for Primary Industries figures show that new plantings last year were around 3000 hectares (compared to 4000 in 2013) - the Forestry Institute says that should be far higher.
Mr Treadwell said there was flooding in Manawatu and Whanganui 10 years ago when it was identified that planting more trees would help in future floods and although there has been some work done on that, it has not been enough. He said although it would be impossible to stop flooding, its effects can be mitigated.
He said since 2003 85,000 hectares of land had been deforested and a lot was probably driven by the Emissions Trading Scheme, either prior to its introduction because foresters were worried they could not convert their land, but also because of conversion to dairy farms.
But the minister responsible for forestry Jo Goodhew said it was not true to say the Government had subsidised dairy farmers.
"I'm going to take issue with the statement that we've incentivised people into dairy, the money we've set aside to promote water storage doesn't just go to dairying."
Ms Goodhew is encouraging the Forestry Institute to take part in the review of the Emissions Trading scheme.