The DAF north Queensland pasture team is setting up some new demonstrations and research trials looking at the best methods of establishing new pastures in the region.  After a decade of testing new grass and legume cultivars, these sites will now focus on efficient and practical ways to establish and manage these varieties on commercial properties to get the most out of them for productivity and profitability.  They also provide the opportunity to explore questions around grazing land management, carbon on properties and emerging tools to measure pasture and animal performance.

Key take-home messages

• Adding legumes to grass pastures benefits livestock production by increasing the amount of high quality (protein and energy) feed in the diet, particularly during the early to mid-dry season when grasses are haying off. This can significantly reduce nitrogen supplement costs.
• There are a range of new legumes available for producers to add to the older reliable cultivars with good options for most land-types in north Queensland. New production systems, particularly the development of ‘production paddocks’ for weaners and steers, are showing considerable promise following recent DAF/MLA research.
• Under the new Queensland Pasture Resilience Program, new demonstration sites are being developed across north Queensland to test and demonstrate these new legumes and production systems. These are to be used to generate producer discussion and help with adoption, plus an updated series of extension resources.

Why legume demonstrations and why now?

Well adapted and palatable legumes enable the introduction of atmospheric nitrogen into pasture systems to drive plant growth and provide high quality leaves (and small stems) over extended times of the year.  This enables cattle to supplement their nitrogen (as protein) needs as grasses decline in feed quality over the dry season and can significantly reduce the use of expensive nitrogen supplements in the dry season.  New pasture legumes and grasses developed over the last 20 years were tested along with older reliable cultivars in recent DAF/MLA trials across north Queensland.  Some of the most useful legumes for areas with an extended dry season include stylos, desmanthus and leucaena (pictured below).

Scaling up of the research has seen the testing of combinations of best grasses and legumes to suit ‘production paddocks’ for weaners and steers with excellent results:  pasture yields 2-4 times those of native pastures in good condition.  A new DAF/MLA program, the North Queensland Pasture Resilience Project, was recently developed to further test and promote legume pasture systems in north Queensland.  This is the first year of the project and there is a key focus on developing demonstrations to assist producers with pasture planning and adoption.

Three types of legumes well adapted to seasonally dry conditions:

Where is the research?

Most of the demonstrations are focussed on the seasonally dry zone of north Queensland, including Gulf River, Burdekin and Herbert catchments.  The properties where the work is being done include weaner and feeder steer operations in areas of natural woodland and treeless plains, plus some historically cleared areas on soils of moderate to high fertility.  Soil types include red and black basalt soils, alluvials, red earths and duplex (‘Goldfields’) soils.

How are the trials set up?

The demonstrations are co-designed with beef producers and usually focus on a research question or demonstrating a proof of concept around establishing or managing legume pastures.  The team aims for a practical focus where uptake is more financially realistic or has lower risk.  There is also an advisory committee of producers, extension specialists, pasture researchers and seed industry representatives to help with design and extension.  The sites are developed and maintained by the DAF team, host producers and contractors.  Field data are mostly collected by the DAF team, although producers or collaborating DAF staff help with weighing cattle at some of the larger sites.  Ag-tech is used where possible to reduce workloads (Optiweigh™) or ensure animal welfare (cameras on waters).

Trials focussed on plant adaptation and pasture production

These are on-property trials using the promising cultivars of grasses and legumes identified in the earlier small-plot studies and developed in previous DAF/MLA projects.  The grasses and legumes were sown as combinations and managed as they might be for dry-season weaner paddocks.  Fertiliser phosphorous and/or sulphur were applied during establishment only to top-up nutrient levels based on soil tests. The plots were grazed during the dry season with a an occasional light wet-season graze to maintain good grass/legume balance.

There are up to 64 combinations of grasses and legumes at each site and each combination is repeated three times.  The plots have been good for confirming which grasses and legumes are adapted to different soil types and identifying the more competitive grasses and legumes and which combine better than others.  The better combinations produced 2-4 times the amount of pasture of undeveloped native pastures in good condition with good yields of high-quality legume leaf in the dry season.  There are three of these trials in north Queensland and one in central Queensland which have been continued under the current project (Table 1).

Table 1. Trials to test combinations of grasses and legumes

Photos of the Mt Surprise site:

Paddock-scale research demonstrations

These include four large-scale trials, some still under development, to test and demonstrate ways to establish legumes or manage in dedicated paddocks for raising weaners or steers (‘production paddocks’).  Each aims to address a different research question raised by producers living in different regions (Table 2).  These are replicated trials with a dedicated effort to collect animal and pasture production data to try to understand the effect certain methods on the grazing system and to look at the economics of putting them into practice.  We measure pasture composition and yields, animal liveweight gain and diet quality to get a picture of how the whole pasture system works.  Baseline carbon is also being measured at one site to understand how the adoption of deep-rooted legumes like stylos could influence soil carbon levels over time.  These trials are up to ~120 ha in total size and require the development of considerable infrastructure including replicated paddocks and temporary yards and careful selection and allocation of cattle to different treatment paddocks.   All involve considerable involvement and dedication by the land owners and the sown pastures team.

Table 2. Paddock-scale research demonstrations to test legume pasture management

Photos of each site are included below:

Practical ‘what if’ and ‘how to’ demonstrations

These are under development and include relatively simple demonstrations on properties to tackle a particular problem or demonstrate a new practice to share with other producers through small group days.  Some are small plot trials testing a range of options, while others are at paddock scale to collect some new information or test and demonstrate ag tech.  Some of these test the historical boundaries of legume adoption and often involve testing particular legumes in new environments to provide options for producers.  This recognises that successful establishment and long-term productivity of legume pastures requires choosing the right legume for the land-type and grazing system being used.  Simple field data are measured based around what the demonstration was trying to achieve for discussion at small-group producer days and summarising as case studies.  These might include animal LWG, success of establishment or changes to pasture composition or quality depending on the research question being considered.  These are an important part of the work as the sites act as a point to get people together providing the opportunity to ask questions and discuss options in a relaxed setting.  The team is aiming to develop more of these over the next few years as the opportunity arises.

Table 3. On-property demonstrations for problem solving and discussion

Some photos of the Georgetown and Richmond are included below:

Interested in finding out more?

All of this work is made possible through the North Queensland Pasture Resilience Project, which is a partnership between the Department of Agriculture and Fisheries, Meat & Livestock Australia and the Australian Government through the MLA Donor Company. A strong focus of the project is to encourage the adoption and use of legume pastures in north Queensland.  The DAF project team includes research and extension officers based in Mareeba and Charters Towers who regularly travel across north Queensland to work at the various sites and for small producer group days and larger field days.  If you would like to know more or get involved in the program, please contact one or more of the following team members:

This work is part of the Queensland Pasture Resilience Program.