The big picture: using wildflower strips for pest control
They may be beautiful, but these strips prove pretty deadly for every farmer's mortal enemy: aphids
News
Cell grazing supports double the livestock per hectare of set-stocking and delivers environmental benefits
Comprehensive study shows multiple positive impacts for both productivity and ecosystem health
Cell grazing has positive effects on soil carbon sequestration, pasture growth, and live weight production per hectare compared to set-stocking, according to a wide-ranging new report.
The four-year study compared cell grazing (CG), using TechnoGrazing infrastructure, where animals were moved every 1-2 days to new, and set stocking (SS), where animals remained in the same area for the grazing season.
The cell grazing method achieved substantially higher pasture growth, with dry matter production nearly 40% higher than set stocking. By the third year, CG areas supported double the livestock per hectare compared to SS - and produced 140% more liveweight per hectare.
Despite more intensive grazing and higher stocking densities, soil carbon content increased in cell grazing enclosures while it decreased in set stocking, indicating higher levels of carbon sequestration.
In a perfect system, livestock would graze all parts of a field equally. In reality, the animals tend to cluster around features like water troughs leading to uneven grazing and bare patches. Cell grazing reduces these problems; animals are evenly rotated around the paddock, grazing more intensively. The pasture then has the possibility to rest and recover from being eaten and generate new growth. In contrast, SS approaches may lead to overgrazing of certain areas, affecting pasture productivity.
“These results give the best evidence yet that ‘It’s not the cow, it’s the how’,” said Rothamsted’s Dr Jordana Rivero, who led the study. “In other words, the way you manage your grazing system is important and can deliver beneficial outcomes. Cell grazing benefits both the farm productivity and some aspects of the environment. Negative environmental impacts like increased nutrient runoff potential or soil compaction were similar between the two methods.”
The study team found a range of other effects including changes in the botanical composition of the two systems. Cell grazing increased the abundance of perennial ryegrass within the sward and maintained levels of white clover, while set stocking led to an increasing abundance of weed species.
“This study is the first time that the two systems have been systematically compared taking into account both productivity and environmental impacts in lowlands in the long term,” said Dr Rivero. “We found no added environmental costs in cell grazing systems despite its greater stocking densities. Moreover, animals in cell grazing plots also had a grazing season three weeks longer, on average, than those in set stocking, potentially reducing cost of winter housing and feeding.”
The study started in 2018 and is still ongoing. The interim report includes the results collated over the first four years. It involves six enclosures, with three replicates of each method (CG and SS). Autumn born dairy x beef steer calves arriving at around 6 months old were randomly allocated to groups. They were grazed for two consecutive seasons with the aim of finishing off grass by 24 months of age.
“Long-term trials are critical to assess any intervention applied to productive systems,” said Dr Rivero. “If we are interested in understanding how the components of the system such as soil, plants and animals evolve over time, and how the system adapts to the new management, we need to run extended studies. And the work is ongoing: A couple of week ago, the fourth cohort of calves were turned out to the experimental paddocks to launch the seventh grazing season!”
Publication
Contacts
Dr Jordana Rivero
Grazing Livestock Systems Specialist
ABOUT ROTHAMSTED RESEARCH
Rothamsted Research is the longest-running agricultural research institute in the world. We work from gene to field with a proud history of ground-breaking
discoveries in areas as diverse as crop management, statistical interpretation and soil health. Our founders, in 1843, were the pioneers of modern
agriculture, and we are known for our imaginative science and our collaborative approach to developing innovative farm practice.
Through independent research, we make significant contributions to improving agri-food systems in the UK and internationally, with
economic impact estimated to exceed £3 bn in annual contribution to the UK economy. Our strength lies in our systems approach, which combines strategic research,
interdisciplinary teams and multiple partnerships.
Rothamsted is home to three unique National Bioscience Research Infrastructures which are open to researchers from all over the world:
The Long-Term Experiments,
Rothamsted Insect Survey and the
North Wyke Farm Platform.
We are strategically funded by the Biotechnology and Biological Sciences Research Council (BBSRC), with additional support from other national and
international funding streams, and from industry. We are also supported by the Lawes Agricultural Trust (LAT).
ABOUT BBSRC
The Biotechnology and Biological Sciences Research Council is part of UK Research and Innovation, a non-departmental public body funded by a grant-in-aid
from the UK government.
BBSRC invests to push back the frontiers of biology and deliver a healthy, prosperous and sustainable future. Through our investments, we build and support a vibrant,
dynamic and inclusive community which delivers ground-breaking discoveries and develops bio-based solutions that contribute to tackling global challenges,
such as sustainable food production, climate change, and healthy ageing.
As part of UK Research and Innovation (UKRI), we not only play a pivotal role in fostering connections that enable the UK’s world-class research and innovation system
to flourish – we also have a responsibility to enable the creation of a research culture that is diverse, resilient, and engaged.
BBSRC proudly forges interdisciplinary collaborations where excellent bioscience has a fundamental role. We pioneer approaches that enhance the equality, diversity,
and inclusion of talent by investing in people, infrastructure, technologies, and partnerships on a global scale.
ABOUT LAT
The Lawes Agricultural Trust, established in 1889 by Sir John Bennet Lawes, supports Rothamsted Research’s national and international agricultural science through the provision of land, facilities and funding. LAT, a charitable trust, owns the estates at Harpenden and Broom's Barn, including many of the buildings used by Rothamsted Research. LAT provides an annual research grant to the Director, accommodation for nearly 200 people, and support for fellowships for young scientists from developing countries. LAT also makes capital grants to help modernise facilities at Rothamsted, or invests in new buildings.