A new economic analysis says farm incomes and the national economy would gain billions if farmers renewed their pasture more frequently.
The report was commissioned by the Pasture Renewal Trust, which was formed three years ago to educate the agricultural sector about the value of improving pasture.
The trust's chairman, Murray Willocks, says current annual pasture renewal rates are about 2% for sheep and beef farms, and 6% for dairy farms.
He says the analysis presents a compelling case for increasing pasture renewal rates for sheep and beef farms fourfold, while those for dairy farms need to double.
Mr Willocks is urging farmers to think of grass as a crop that needs to be managed annually, saying the lack of investment in pasture improvement, new plant species and technology is holding back production.
He says financial pressure from the recession may have slowed investment in pasture renewal, but farmers need to remember it's a good investment.
Billions at stake
Mr Willocks says the report put the value of pastural farming at $20.5 billion or 12% of GDP, and the value of increasing the rate of pasture improvement at an extra $1.6 billion at the farm gate or $3.2 billion at GDP level.
He says New Zealand would need to attract an extra 460,000 international tourists a year to generate $1.6 billion in economic gain.
The analysis was carried out by economic research company BERL.