Does New Zealand need regenerative pastoral agriculture?
The rapidly growing interest in regen farming has raised the ire of many dairy scientists and consultants. They make critical comments such as ‘NZ agriculture is already regen’, ‘ it has no definition’, ‘there is no science behind it’ etc. Regardless of how much truth there is to these criticisms, I take the view that you that, given that the interest in it is being driven largely by farmers themselves, we need to look at it very carefully.
I have come to the conclusion that many farmers, dairy farmers in particular, are becoming increasingly concerned about the ever-increasing pressures on them to adopt new practices to increase production just to stay profitable. Their lives are becoming increasingly complex and stressful, for no benefit. They instinctively know that many of these practices, such as increasing bought-in feed, and replacing permanent pasture with short-term ryegrasses needing ever-more fertiliser N as clover disappears, are not good for the soil or the environment. Then there is the ongoing difficulty in finding staff.
The staffing problem is one of the key drivers towards once-a-day (OAD) milking, or variations such as 3 milkings every 2 days (3/2) etc. The latter appears to result in no significant drop milk-solids production.
Interestingly, while dairy farmers’ rapidly increasing interest in 3/2-type milking – a very significant change to the traditional twice a day – is being taken very seriously by scientists, research establishments and consultants, their equally strong interest in the potential environmental and lifestyle advantages of regen farming is being rubbished by virtually all of them. They simply cannot bring themselves to accept that many changes in dairy farm practices introduced to increase production in the last 2 decades have actually been detrimental to the environment, and in so doing have reduced the pleasure farmers get from what they do.
So I thought that if I came up with a scientifically-orientated definition and rationale of the objectives of regen farming in NZ that was acceptable to farmers, it might help it to be taken more seriously by those who should.
Objective:
Regen agriculture strives to optimise the production of nutritious food, while restoring and protecting the environment, in so doing bringing back the respect for and enjoyment of farming as a way of life, and encouraging practices that sequestrate soil organic carbon.
Key practices:
– avoiding ploughing to maintain soil carbon;
– rotation grazing to residuals of no less than 2500 kg DM/ha. Overgrazing encourages nutrient and soil losses, compaction, pugging and reduction in soil carbon. The 2500 DM minimum could be replaced with a maximum of 5% bare soil.
– allowing pasture to grow taller; encourages diversity, shades out weeds and increases soil carbon;
– maintaining pasture covers in winter by feeding out hay rather than growing winter crops;
– limiting soil Olsen P levels to 20 and maintain optimum production, by the use of sustained-release non-leaching fertilisers such as RPR. Soil particles in the top 2cm (often with Olsen P much >20 from using excess soluble P), are the main source of particulate P in run-off.
– minimise nitrate leaching and run-off, and gaseous losses of ammonia and nitrous oxide, by using new-gen N ferts such as prilled, inhibitor-coated urea.
– applying effluent to as much of the farm as possible, with 10ml application rates.