Scientists are delving deeper as they search for new ways of boosting production on the farm. Earthworms are playing a key role.
AgResearch soil scientist Alec Mackay says earthworms play an important role in conditioning and cultivating the soil.
He heads a team that's surveying life in the soil and investigating how creatures such as worms, mites, springtails and nematodes might be used to improve pastoral farming.
But earthworms and other useful soil-dwelling life-forms are in short supply in some places.
Dr Mackay says his team has just finished an earthworm survey with farmers to see what the potential might be for building up populations in areas where they're lacking.
He says it's an oportunity to introduce a greater range in pastures across New Zealand.
Dr Mackay also says people may be surprised to learn that in an average sheep paddock, the life underground weighs more than the livestock.