Forage index helps ID best cheap feed

Forage index helps ID best cheap feed


dairy incomes face the crunch farmers seeking cheaper feed are getting a better idea of the value of the grass beneath their feet.

DairyNZ’s Forage Value Index (FVI) is almost three years old and the pasture ranking system has had a quiet presence in the market. Manager Cameron Ludemann is hoping tough times this season will see farmers take a closer interest when using it to regrass.

“Farmers should be looking harder at the cost of pasture renovation compared to getting supplement bought in. JWe have found farmers generally understand the concept of ranking pastures, based on their experience with the Breeding Worth (BW) system.”

Run independently of seed companies through DairyNZ, the FVI was created to rank pastures based upon seasonal drymatter production. 

Ludemann said that to date farmer awareness had been relatively high, with almost 50% knowing about the index. 

Hopes are to push that to more than 70% this year, and make it an integral part of the pasture renovation process that consists of selecting the right paddock, selecting the right cultivar, establishing pasture well, and managing the pasture to get its full genetic potential.

“In that respect it is very similar to BW, where you select stock with the best genetic potential but still need to manage all aspects to get the full potential of that stock.”

Three years on DairyNZ plant scientists are working to include additional index parameters in the assessment, like metabolisable energy (ME) levels, additional nutrients, and a value for the pasture’s persistence. 

So far DairyNZ has acquired two years’ worth of data from Canterbury farms on ME, and estimates are it will be a year before that data can be included.

“Obviously persistence is a longer term trait that is limited at present by the amount of data we have to work on, but that will increase over time,” Ludemann said.

The FVI has split the country into four areas, with cultivars ranked within those areas. Ludemann said it was unlikely the country would be split further at this stage, with production from those four areas proving sufficiently accurate. 

“The analysis showed we really have two ‘mega’ environments, the upper North Island and the rest of NZ.”

Farmers familiar with the NZ Animal Evaluation unit’s regular re-assessment of bulls’ rankings will find a similar process evolving with the FVI. Pastures are reassessed annually based on new data, and rankings adjusted accordingly.

Ludemann wants to expand understanding of the FVI within rural retailers, and there is hope seed companies may consider signing up for a licensing agreement to have FVI included in seed labelling.

The measurement of persistence is a challenging one in seasonal pasture systems that get hit by bad weather, and requires more time to build an accurate indicator to include in the index. 

Ludemann hopes ultimately it might be possible to “crowd source” data on pasture persistence, through dairy farmers linking their drymatter recording back into DairyNZ’s index.

“We are also asked about what the effects will be of having lower nitrogen limits on pasture production and rankings. You may find some grasses perform well now but will not be as good if nitrogen in reduced. This is something we will have to look to build into it in the future.”

Ludemann said the FVI, while a work in progress, remained a far better option for selecting pasture given its high level of independence and validity.