Article by Dairy Australia consultant Ruairi McDonnell for DairySA.
Australian dairy farmers and producers can now make better informed decisions when selecting ryegrass cultivars following the release of Dairy Australia’s new and expanded 2023 Forage Value Index (FVI).
The Forage Value Index (FVI) is a tool that helps Australian dairy farmers and their advisors to select the highest yielding and most profitable ryegrass varieties for sowing.
The FVI has been available for a few years now and each year, new data from various sites across all of South-East Australia are added to further strengthen the reliability of the FVI tables. Data from each site is combined into an aggregated dataset to predict the highest performing varieties in each of the three main ryegrass species – Perennial, Annual and Italian ryegrass.
How is it calculated?
The FVI value for each variety is calculated by multiplying the Performance Value of each cultivar (i.e. total kilograms dry matter produced per hectare per season) by its Economic Value (i.e. the estimated value of this extra production per season). Performance Values for each variety are determined by industry assessed, independent trial data generated by the Pasture Trial Network (PTN). To be included in the FVI database, each cultivar must have data from at least three trials that have been conducted using strict industry approved protocols. For Perennial ryegrass, trials must be three years in length, whilst Annual & Italian ryegrass trials must be a minimum of one full growing season.
How to use it
Once you have decided which species you are sowing (Perennial, Annual or Italian ryegrass), simply look at the FVI for that species and select a high performing cultivar towards the upper end of the list. There are also seasonal yield tables available to indicate which cultivars perform best across summer, autumn, and winter when pasture production may be of greater value than in spring depending on your farm system, calving pattern etc.
How to use the FVI in South Australia
Not every single corner of the dairy producing regions across Australia has trial data available. This is often due to several reasons including availability of trial operators, sites and the demand from the seed companies participating in the Pasture Trial Network to evaluate varieties in environments closer to their main target markets.
This doesn’t mean that the FVI cannot be used by farmers in the DairySA region. Firstly almost all of the varieties sold in places like Victoria and Tasmania are also available in SA. There is actually a perennial ryegrass trial that contributed to the FVI in Mt Gambier that ran from 2016-2019. In addition, in 2023, a new perennial and Italian ryegrass trial for PTN will be sown in Bool Lagoon under irrigation.
For farmers in the South-East of SA, it is recommended to use the South-West Victoria FVI when selecting varieties. For farmers closer to Adelaide, if selecting Annual or Italian ryegrass varieties it is recommended to use the Northern Victoria FVI as a guide to the value of each variety. In time, it is aimed to have trial data from all of the important dairy producing regions of Australia contributing to the FVI.
Additionally, farmers using continental Tall Fescue will be able to access trial information from a new DA funded individual PTN trial with 18 Tall Fescue varieties that is finishing in June 2023 in Warrnambool. This trial includes both yield and forage quality information on each variety. It will be publicly available on the PTN website later in 2023 after the trial is fully completed and statistically analysed.
As the volume of data from the PTN and FVI continues to grow, farmers can become more confident in the precision of the rankings on the FVI. Furthermore, forage quality information on each variety in perennial ryegrass has been gathered and will be analysed in 2023 with a view to adding this information to the next update of the FVI.
Pasture Trial Network – individual trials
It is also possible to look at the individual trial results that are used to generate the FVI rankings. For example, if you are based in a particular region and wish to look at the individual trial results from a local site (including the perennial ryegrass trial at Mt Gambier), you can do so on the PTN website by following this link. There are over 100 independent trials across all species available on this website over several years.
To see a copy of the latest Forage Value Index, head to the Dairy Australia website www.dairyaustralia.com.au/FVI (where there is a much more comprehensive frequently asked question document available).
