Dadswell bridge perennial pasture multi-year trials

The Dadswell Bridge area is located in the Wimmera region of western Victoria (Australia). The common practice for pasture fertilisation in this region is to apply periodically e.g. on a biennial schedule (every second year). The aim of this trial is to mirror this practice and test which fertilisers perform best using biennial rates and application schedules. While a year one response is important, the trials main aim is to ascertain which (if any) of the fertilisers can best maintain production in the second year. Fertiliser application rates for pasture in this area are typically low, which is reflected in the trial.

Aim

To compare the efficacy under replicated field trial conditions of various fertilisers when used on a biennial (every second year) application rate and schedule. The trials main aim is to ascertain which (if any) of the fertilisers best maintains production in the second year.

Method

To compare the efficacy under replicated field trial conditions of various fertilisers when used on a biennial (every second year) application rate and schedule. The trials main aim is to ascertain which (if any) of the fertilisers best maintains production in the second year.

Site Characteristics

• pH 4.5, high aluminium, high PBI
• Clover/phalaris pasture mix.
• Application rates based on an average annual spend of $28/ha (excl. freight, spreading & GST).

Products Trialled

• MagPhos
• BioAgPhos S10
• BioAg Superb
• Single superphosphate (SSP)

Results

2015
Fertiliser was applied in this year only. 2015 was a very dry season, with very low levels of dry matter produced across all plots. The best response came from sites applied with fertiliser that contained sulphur in a sulphate form (SSP and Superb).

2016
No additional fertiliser was applied. 2016 was wetter than average, and dry matter production was greater for all plots compared to 2015. Also in 2016 we saw the greatest difference in dry matter production between the plots.

In 2016 the BioAgPhos S10 plot delivered significantly higher dry matter than all other plots. The next best dry matter production was from the BioAg Superb plot, and then the SSP plot.

Total production kg/ha

Conclusion

BioAgPhos S10 followed by BioAg Superb delivered more dry matter in both the second year, as well as in total across the two years. While seasonal conditions impacted the overall dry matter production for every treatment, it is evident that the availability of sulphur and a sustained release form of phosphate (as delivered by BioAgPhos S10 and BioAg Superb) produced greater production across two years.