Thursday, 27 June 2024 11:55

Deferred grazing back in play

Written by  Peter Burke
AgResearch’s Katherine Tozer (middle) explaining deferred grazing at the Fieldays. AgResearch’s Katherine Tozer (middle) explaining deferred grazing at the Fieldays.

With farmers facing challenging financial times, a move to deferred grazing is one of many cost-effective systems available to them.

That’s the view of AgResearch scientist Dr Katherine Tozer who was at Fieldays this month talking to farmers about this option. The concept is not new and some of the early research dates to the 1950s and 1960s by one of the early ag scientists, Eddie Suckling. In 1951 he presented a paper at the Grasslands conference showing the success of over-sowing pastures in autumn as opposed to spring.

In recent years there has been a revival of this concept, coming with the support from the likes of DairyNZ and Beef+Lamb NZ. To that end, Tozer and others have done further research to fill in gaps from early investigations into this pasture management tool.

Put simply, deferred grazing is about resting or locking up a limited amount of the grazing platform for a period between mid to late spring and late summer. Tozer says in the case of dairy, this could be up to10% of the pasture and maybe slightly longer for sheep and beef farmers, depending on their individual feed and water availability. The overall aim of the system is to improve pasture quality and at Fieldays there was significant interest in this option.

She says this involves the farmer assessing what grass species – such as plantain or other mixtures – will be best, and then over-sowing these on the ‘deferred paddocks’.

“When the stock are brought in to eat the deferred pasture, they will trample in the seed and ensure that it has good soil contact and will establish easily. It also means that as the grass is eaten down, the seeds will have light – necessary for growth, but also some protection from the remaining grass,” she says.

The advantage of this, says Tozer, is that the longer grass in the paddock will retain soil moisture which is good for germinating the seed. She says the longer grass will also prevent the paddock from drying out too quickly.

About The Research

The aim of the research by Katherine Tozer and others is to get some hard data on the benefits of deferred grazing. She says for example they are interested in seeing how the system improves root depth, pasture resilience and if it has any impact on carbon sequestration.

“So, we have got two sites [with] rhizotrons installed. These are clear plastic tubes inserted at an angle into the ground, and with the aid of a camera we can measure of root growth over time to see how it’s changing, in terms of seasonal growth, and how deferred grazing is having an impact as opposed to not using deferred grazing,” she says.

Tozer says one issue of concern raised about deferred grazing is the risk of facial eczema due to dead grass in paddocks where spores are commonly found. She says their research shows that when spore counts occurred in deferred grazing pasture, these were much lower than in conventional pasture.

For Tozer and advocates of deferred grazing, the message at Fieldays to farmers was ‘give it a go’. Start small and trial the idea to see how it works. She says it may not be for everyone, but is a good option – with one proviso. Tozer says deferred grazing will likely not work in a paddock where browntop or weeds are very dominant. She says browntop is very difficult to work with and paddocks that are already good will benefit most from deferred grazing and will likely improve profitability.

More like this

'Let's not chase rainbows'

Farmers with experience and breeding knowledge are deeply concerned about the pressure to breed for low methane sheep traits and its effects on other important traits they have been pursuing over the last 100 years.

Finalists named for Primary Industries awards

One of the country’s top trade officials, a respected farmer and orchardist and a radio presenter are in the running for the 2024 Outstanding Contribution to New Zealand's Primary Industries award.

'Living labs' to tackle emissions

Living labs that bring together expertise at locations around New Zealand are among potential solutions identified by researchers to help the country move towards a more climate resilient future.


Red tape 'blocking access to crop production products'

Outgoing chief executive of Horticulture New Zealand, Nadine Tunley has taken a swipe at government agencies for the “costly and lengthy regulatory approval process” to get new crop protection products registered.

Farmers back ACT MP's bill

ACT MP and Northland dairy farmer Mark Cameron is lodging a new member’s bill that would prevent regional and district councils from regulating greenhouse gas emissions.


Cream of the crop

One of New Zealand's largest dairy farmers won the 2024 'Food, Beverage and Fibre Producer' award at the NZ Primary…

Machinery & Products

Revamped automatic calf feeder

JFC Agri, the family-owned manufacturer of agricultural products from Galway, Ireland, used Fieldays to launch its innovative Evolution range of…

ErgoPOD set for 2025 farm debut

Waikato Milking Systems has unveiled the final production version of its ErgoPOD, a state-of-the-art semi-robotic technology designed to increase milking…

» Latest Print Issues Online

Milking It

100-year-old milk powder

OPINION: A 100-year-old sample of milk powder from Ernest Shackletons’ first solo expedition to Antarctica has been analysed by scientists.

Farmer feedback

OPINION: Sticking with the NZ Primary Industries Summit, Fonterra chief executive Miles Hurrell’s quip about the milk price has been…

» Connect with Dairy News

» eNewsletter

Subscribe to our weekly newsletter