Dual-purpose peanuts offer high protein fodder option

The Grain and Graze North project, led by CQUniversity, has been evaluating different peanut varieties and breeding lines from the Bega-CRDC peanut breeding program over a three year period.

One of the trials at Deneliza Downs near Emerald has evaluated the peanut varieties Alloway and Kairi, looking at the impact on peanut yields and the volume of biomass harvested for livestock fodder.

Peanut hay cut and baled at Emerald contained 23pc protein and 71.8pc fibre.

Preliminary results from the research trial indicate that peanuts can provide up to one to 2.7 tonne per hectare of dry matter biomass from an in-season cut providing cattle fodder without significantly compromising end of season nut yields.

The impact on yields and the volume of biomass harvested varied from site to site.

Peanut yields were comparable in plots that were cut for hay, but the yield loss was only noted where late season planting, and soil moisture stress occurred after the in-season biomass cut occurred.

The peanut plants recovered well after the in-season biomass cut, and they typically produced similar amounts of dry matter as the uncut plots at the end of the season of approximately 2t/ha.

Mechanised in-season hay harvest was completed successfully in 2024 using a disc forage mower.

Once cut the peanut hay was wind rowed for drying with a traditional rotary rake.

When moisture was below 14 per cent, peanut hay was square bailed using a traditional small square hay baler.

There are two harvest points for peanut hay, a first cut at 75 -80pc ground cover and a second cut hay after threshing.

For harvesting the peanuts, a peanut digger was used to dig and invert the peanut plants so that the peanuts are exposed to the air for drying.

The peanuts are separated from the plant using a peanut thresher when the moisture is between 10 and 16pc, normally 4-10 days after digging.

CQUniversity lead researcher Dr Tieneke Trotter said dual purpose present an opportunity for grazing operations to produce high quality feed for livestock as well as the benefit of a nut production for human consumption.

"This allows peanut producers to access an entirely new market, servicing the livestock industry and helping to provide high quality feed, which, if cut for hay can be stored for supplementary feeding when there is a feed gap," Dr Trotter said.

"The high quality feed could also assist livestock producers to access higher quality meat markets."

Dr Trotter said there were many positives for producers to consider diversifying their operations into dual purpose peanuts, including assess to an in-season payment for hay, followed by an end of season payment for nuts.

"Anecdotally there appears to be a good opportunity to access markets for peanut hay, it appears to always be in demand," she said.

"As Australia still imports peanuts, there is a market opportunity for any new growers looking to producer peanuts."

There could be an opportunity for in season livestock grazing, but Dr Trotter said comprehensive trials would need to validate this opportunity.

On April 18, central Queensland growers and agronomists were able to inspect the latest dual-purpose peanut crop trail.

Dr Trotter said peanuts were planted in early December 2023, and grown under irrigation over summer in Emerald.

"Half of this crop was cut using a slasher, raked with a hay rake and bailed in the paddock," she said.

"This was the first time peanut hay was bailed in season using large scale mechanical equipment and the plant response is promising.

"Although the trial has not yet been harvested, it is anticipated from previous seasons work that the total yield won't be significantly reduced, but that there might be a reduction in the peanut grade."

While this season's Emerald crop has not yet been harvested, Dr Trotter said the Alloway responded better to in season cutting for hay compared with other varieties in the past.

"Typically, there hasn't been a major effect on overall yield, although the size (grade) of the peanut has been reduced," she said.

"While this isn't desirable, the cost benefit from the hay, coupled with most nuts still achieving the highest pay grade category means that dual purpose peanut production does show some promise.