Value of poultry manure increases

Rocketing fertiliser prices are making farmers much more aware of the benefits of substituting poultry manure for at least some artificial dressings.

That’s the experience of a Kent contractor who took over removing and spreading the output of Cranbrook egg producer Fridays last autumn.

“We’ll be handling about 40,000t a year of poultry manure from several sources, including free-range and organic as well as intensive systems,” says Steve Bryant of Groundscare and General Services.

Having advertised the service, Mr Bryant and brother Andy now supply farmers up to 60 miles from their Rolvenden base, charging £10-20/t for delivery, according to distance.

“We offer to spread it with our Claas 180hp tractor and Bunning rear discharge spreader at £35 an hour. We can apply it pretty accurately at 10m widths, generally at 3t/acre, though I tend to leave the farmers to decide on the rate.”

Having plenty of growers prepared to accept those charges is a sure sign that the materials’ properties are becoming better appreciated, says Mr Bryant.

“It wasn’t so long ago that you could get it almost free. Now it’s seen as a valuable by-product.

“The big advantage is the financial saving. We reckon that, on average, someone growing 10t/ha of wheat should save £127/ha on phosphate and potash alone over three years. That’s with P and K fertiliser costed at £500/t.”

Most poultry manure also contains nitrogen and lime, he notes. “We regard that as a bonus.

“We’ve used it ahead of oilseed rape and had a lot of interest in it for maize, which is a very hungry crop.”

Most applications are planned for late summer and autumn. Under the new NVZ rules, the latest they can be made is 14 October, and on sandy or shallow soils the cut-off date is even earlier, depending on the crop.

“We tried to get most done by 1 October, but the wet weather didn’t help.”

Public reaction must be acknowledged, says Mr Bryant. “When we spread, there’s bound to be a certain amount of smell. But we work to the borough councils’ code of conduct, which is really about using common sense. For example, we won’t spread right next to houses.”

Decade of use highlights pros and cons

Keith Millen, who has 120ha (300 acres) of mainly Weald clay at Wagstaff Farm, Biddenden, is an enthusiastic long-term user of poultry manure from a deep litter system.
“I’ve been taking about 1000t a year for about 10 years and it’s gone on everywhere – on the hops, arable and grassland,” he says. “We apply it ourselves using a slurry spreader, which gets it on evenly enough.”
Before then, the land’s phosphate and potash soil indices were mostly zero, he notes. “Now they’re all where they should be – around three. We’ve also raised our pH levels.”
Mr Millen, pictured above (left) with contractor Steve Bryant, employs analyses supplied by Fridays to adjust his inorganic fertiliser dressings as necessary. “Generally, I reckon every ton of 50% dry matter deep litter contains 23-24kg of P and K, and we usually apply about 4t/acre.”
Adjusting for the nitrogen content can be tricky. At first he didn’t realise the manure’s strength, and much depends on how much is lost before crops can take it up.
“It can leach quite quickly, but we always make an allowance – on some grassland, we’ve never put any bag N on,” he says. “And for one crop of Xi19 wheat, 100 units an acre was plenty.”
Until now, the decision has been based mainly on how the crop looks, he admits. “But now we’re in an NVZ for the first time, the calculation could get more difficult.”
Carting on his heavy clay can bring problems, he says. “We can get compaction, especially around the gateways.
“But overall there are definite savings and benefits. Yield, bushel weights and Hagbergs are all usefully affected.”
However, with grain prices no better than in 1991 and other input costs rising, there is clearly a ceiling beyond which its use would be hard to justify, says Mr Millen. “If I had to pay much more for it, it would become uneconomic.”

Need a contractor?

Find one now