''In terms of numbers it's not going to make a major difference to emissions,'' she said in reply to a question from the floor at a ''Carbon Unravelled'' meeting in Pleasant Point last week.
''But in terms of showing how it can be done, we can make a difference. We have to do what we can.''
Dr Wreford told a meeting of about 50 people considering the issue ''making sense of carbon on your farm'' that New Zealand's agricultural sector accounted for 48% of the country's emissions.
Between 1990 and 2017 there was a 13.5% increase due to doubling of dairy production and a 650% increase in N fertiliser application.
The Government's proposal was to price livestock emissions from 2025 at the farm level and fertiliser emissions at processor level. Price details were still to be decided.
In summary, she said the pricing would be difficult for farmers unless land use changes were made, reducing methane by more than 10% would be hard, trees and carbon trading provided some opportunities for land management, and acting now would be less painful in the long term.
''If we act now there will be time to do it gradually and not destroy communities and to learn from the mistakes as we go along.
''If we're going to delay then we're going to need drastic measures to plant huge areas of land.''
Anne Gordon of Te Uru Rakau provided information on the one billion trees programme and funding available for planting - for natives $4000 per hectare, natives reversion 5ha-300ha, $1000 per hectare; and manuka/kanuka planting 5ha-300ha, $1800 per hectare.
Top-ups were available for fencing and ecological restoration, and native planting.
Radiata pines had been restricted from the ETS scheme for six years, including the year of planting.
Ms Gordon said there was usually a two-month turn around once applications were received.
-By Chris Tobin
