Many farmers growing legumes for the first time have been asking how to store and feed their crops. Ann Hardy visits a Cumbrian farm where a unique approach to bean preservation has proved to be a success.
Cumbrian beef, sheep and arable producer James Marshall entered the world of growing and feeding beans with some trepidation.
A lack of information on how to preserve and store the crop, combined with little industry advice on how to incorporate beans into a ration, could easily have put him off the idea altogether.
But as manager of the Mounsey-Heysham family’s Castletown Estate, which comprises 1,740 hectares (4,300 acres) between rivers Eden and Esk to the north west of Carlisle, and includes 1,093ha (2,700 acres) of environmentally sensitive salt marsh, he believed he had to find a way.
Mr Marshall knew beans could help him meet the Basic Payment Scheme’s greening rules, both through achieving the crop diversification required and in the creation of Ecological Focus Areas.
And he knew their high levels of protein and nitrogen-fixing credentials would be of commercial value to the estate.
Describing the 625-head enterprise, which comprises 60 native suckler cows and their progeny and about 500-head of bought-in stores, he says: “We particularly wanted to produce home-grown protein for beef.
“But we had always bought-in our protein in the past and did not really think we would be able to grow pulses successfully.”
The farm is low-lying, rising from sea level to about 11 metres (36ft) above, and holds high levels of ground water in some areas for much of the year.
The salt marshes, which carry cattle through summer, as well as the farm’s salt marsh lamb, which is destined for Marks and Spencer, have to be managed with the utmost sensitivity and in accordance with the tides, and are part of an environmental scheme with Natural England.
But Mr Marshall need not have worried about the farm’s ability to grow beans and recognises, even in a difficult year, the crop has been a success.
He says: “We planted our first 70 acres of spring field beans last year, when the season was cold, wet and late. They were in the ground by late March to late April and we harvested them between September 22 and late October, although ideally they would have come in earlier.”
The first batch of 14ha (35 acres), planted on the farm’s lightest, sandiest soils, was harvested with a combine, coming in at an ‘unexpectedly high’ freshweight yield of 10.6 tonnes/ha (4.3t/acre) and at a moisture content of about 35 per cent.
When the decision had to be taken about the beans’ preservation, Mr Marshall turned to crimping, a process he routinely employs with moist cereals, involving rolling grain, preserving with an organic acid-based product, and compacting and sealing in a pit on the day of harvest.
The process is said to suit the farm well, with its absence of grain drying facilities and a limit on the availability of dry storage.
He says: “If I have to combine when the crop is dry, I consider I have failed.”
However, although he could see the attraction of the crimping process for preserving moist beans, he knew excluding air from the clamp, which is essential for prevention of spoilage, would be difficult to achieve with such a large ‘grain’.
It was when faced with this dilemma he had the idea of mixing rolled beans in a wagon in a 2:1 ratio with brewers’ grains, and applying the same preservative he had regularly used on his crimped cereals.
Michael Carpenter, northern regional manager for feed preservation specialist Kelvin Cave, was supportive of the approach, acknowledging the difficulty of achieving anaerobic conditions in the clamp for a crop such as beans.
He says: “Brewers’ grains seemed the perfect product to fill air gaps between beans and the crimping product James chose would rapidly reduce the pH of both feeds in the mix.
“This would mean retaining crimped beans’ maximum nutrient value, achieving a controlled fermentation and protecting both components of feed against spoilage organisms which could otherwise cause deterioration at the opened feed face.”
Mr Marshall concurred even the brewers’ grains benefited from the extra preservation and lasted far longer than would typically be expected.
He says: “Brewers’ grains in a pit in August quickly go mouldy. After about two weeks, you have wasted a lot of energy and you start to see yeasts and moulds.”
The new mixture would last as long as required and could either be fed as a high protein concentrate (see panel) as a summer buffer feed to the finishing group, or used in winter as part of the total mixed ration.
Compiling the basis of the TMR himself, and fine-tuning quantities through the Kelvin Cave rationing programme, Mr Marshall has arrived at two rations – for growing and finishing groups – which have proven to be effective, highly palatable and safe (see panel).
He says: “We feed quite a lot of wholecrop cereal, usually barley, so this is relatively low protein and complements the high protein of brewers’ grain and bean mix in the finishing ration well.”
Added to this is fruit peel and crimped barley (both relatively low protein), together with a high energy, high protein syrup produced as a by-product of bio-ethanol production.
In the overall analysis, the finishing diet delivers metabolisable energy of 11.86MJ/kg DM, 14.88 per cent crude protein, 37.02 per cent starch and 37.13 per cent neutral detergent fibre.
Performance on both rations has exceeded expectations, with finishers gaining 1.8kg per day compared with a predicted daily liveweight gain of 1.6kg.
Mr Carpenter attributes the better-than-expected performance in part to the ration’s high palatability and intake characteristics and the rumen-friendly nature of ingredients.
He says: “Starch in the ration is slowly fermented in the rumen, while the ration is also high in digestible fibre with plenty of scratch factor.”
Mr Marshall says: “We have no problems with acidosis or laminitis and by weighing finishing cattle every two weeks, we find ourselves moving animals through the system more quickly than in the past.”
Specialising in native beef, including four types of Galloway (Belted, Black, Dun and White), as well as White and traditional Shorthorns, Aberdeen-Angus, Herefords and Highlands, he has added dairy crosses and even pure Holsteins as opportunistic purchases.
Cattle are bought throughout the year between 12 and 18 months at 350-550kg and will stay on-farm for about six months to up to a year, and are destined for a range of outlets, from local butchers to the Morrisons Traditional Beef Range.
Having taken half his bean acreage as whole-crop last year, Mr Marshall plans to increase this to 34ha (85 acres) and harvest it all as crimp.
He says: “I hope to crimp it all as it means beans will come off earlier and will help the following crop and, budgets permitting, we plan to install more clamps.”
The farm’s agronomist, Simon Nelson from Agrovista, says: “A lot of beans on this farm were grown on light, sandy and hungry soils, which have little residual nitrogen.
“Beans which were harvested last September have been followed by a hybrid barley, so the expectation is we will have higher yields from this year’s barley, because it is following a nitrogen-fixing crop.”
Analysis of beans/ brewers’ grains mix (on dry matter basis):
Finisher ration fed ad-lib (in kg freshweight per tonne of mix):
Grower ration fed ad-lib (in kg freshweight per tonne of mix):