Research supports baling silage under rotational system

New research into baled silage has highlighted its potential use as a grassland management tool, helping farmers to maximise the use of cheaper, grazed grass whilst producing a high quality forage source for use as buffer feed.

At the same time, investigations by The Institute of Biological, Environmental and Rural Sciences (IBERS) into using alternative crops other than grass for baling suggest farmers could make valuable savings – and increase yields.

The details are contained in the latest UK and Ireland market report into the silage market from Dow, which also outlines how the baled silage system is increasing in popularity – according to a survey carried out for the report 98% of respondents baled at least some of the grass they ensiled in the 2006 season.

"Silage remains one of the cheapest winter feed options for livestock, and more farmers are seeing the benefits of baling for the high quality fodder it generates, the handling and feeding flexibility it brings and the low losses compared to clamp systems," said Norbert Schulze, Silage Marketing Manager at Dow. "However, we are beginning to see a group of progressive farmers seeking further advantages by using baling in new ways that also generate more efficient land management and higher forage quality."

Moving to rotational paddock grazing and setting aside a paddock for baled silage production can help maximize grass utilization by avoiding topping any over-supply when growth is rapid. Topping is often done after clamps are closed and can’t be ensiled, resulting in waste of labour, fuel and grass.

"Using a rotational system in combination with baling means grazed grass use can be maximized but at the same time high quality silage can be produced in convenient bale sized quantities for feeding when grazed grass supply is insufficient to meet livestock’s intake requirements," continued Mr. Schulze. "Provided excessive nitrogen fertilizer is not applied, silage can also be harvested earlier than the standard six week re-growth period if grazing becomes short."

Baling also can help to enable ’rapid harvesting’ when the weather is against large scale clamp production. Baling silage from daily harvestable areas in a "smash and grab raid" enables a harvest of easily storable, high quality silage from a crop that could otherwise be ruined.

Additional research from IBERS into using alternative crops as part of the rotation system highlights further benefits: "Introducing legumes such as clovers would support such a rotational approach, as the enhanced soil fertility will make other crops in the cycle more profitable," explained Dr. Dave Davies, Silage Researcher and Agricultural Outreach Manager at IBERS. "Farmers could also save on fertiliser costs as legumes ’fix’ their own nitrogen - it is estimated that dairy farmers currently applying 200kg N/ha/year in fertiliser could drastically reduce their nitrogen applications without a reduction in forage yield if they put white and red clover in their grazing and silage leys respectively."

There is also evidence to suggest adding legumes such as red clover to a silage mix can significantly increase milk yields. Recent studies at IBERS into big bale silage fed to dairy cattle demonstrated that a 50:50 mix of grass and red clover on a dry matter basis resulted in a yield 3.7 kg/day higher than a grass only silage diet.

Such results depend on the ability to store baled silage effectively - IBERS recommends wrapping silage bales at the point of storage with six layers of film, as this provides an optimum barrier to oxygen which reduces respiration losses and prevents mould and yeast growth. Wrapping should ideally be done within two hours of baling to reduce respiration losses and improve fermentation quality.