IMPROVED FERTILISER MANAGEMENT REDUCES SILAGE SHORTFALLS

Fine-tuning grassland management and integrating this with a flexible TMR system are helping one Lancashire dairy farming family get the most out of home-grown feed resources.

Using Ammonium Nitrate fertiliser in favour of the farm’s usual urea produced a 21% increase in silage in trials at J. and S. A. Lancaster’s Paradise Farm in Horton, Lancashire, last year. With the use of a Sulphur compound also adding 0.5t DM/ha to grass yields, the results are leading to a rethink of fertiliser practice following a difficult year when silage stocks have been low and bought-in fed bills high.

 “We’re always looking for new ways to improve the efficiency of our production,” explains Jos Lancaster. “Getting the most out of our grassland is absolutely key and we’ve learned a lot in recent years about managing this better, but there are always new techniques to learn and different thinking to consider.”

The farm’s 400 cow flying herd is managed by Jos and his wife Sally plus their son Daniel with all calves sold at one-month old and 100 in-calf heifers from Holland and Germany entering the herd each year as replacements. With milk quality more important than outright yield for a yoghurt contract with Lancashire Dairies, the farms 460 acres of grass and 50 acres of wholecrop form the basis for producing 8500 litres/cow/year at 3.45% protein and 4.45% butterfat. Making full use of home-grown forages has been the foundation of the farm’s system for many years with New Zealander Sally’s influence being key to this, Jos says.

“We’ve used a paddock grazing approach for nearly 20 years now using a plate meter to measure grass and rotating our grazing around the farm, as dictated by this. “I would say efficient use of grazing is the number one priority for us allied to the use of a good silage-based TMR for the winter.” The herd is divided into two groups of 150 Spring and 250 Autumn calvers, Jos explains.

 “Come turnout, the Autumn calvers that are back in calf tend to go out first with the Spring calvers held back until a bit later. Once the Spring calvers are out, we usually bring them in at night for a few weeks. “As the summer progresses, we revolve this around so the Spring calvers stay out longer and the Autumn calvers come in a bit more as the days shorten.” Although, treating the herd as a single group has been tried it’s too many cows to manage, especially in the Spring, he points out.

 “I think if they’re left out at night they graze better and make more use of the grass and that’s essential, so we’ll try and manage it so we get as many out day and night as possible this year.” Winter rations for the high yielders are based on the grass silage and wholecrop with 7.0kg rapeseed meal and 12kg pressed sugar beet pulp to provide 30kg/day of milk. Anything more than this is provided by a top-up of concentrate fed in the parlour, Jos explains. “The aim is to get 4000kg/cow from forage and whilst we’ve managed to increase forage utilisation steadily in recent times, this last season we’ve been very short of silage.” With land predominantly on heavier soils and rising to 600’ above sea level in places, wet conditions can make optimum grass utilisation difficult.

 “Grazing was hard work from August last year because it was so wet and having to bring the cows in early because of this didn’t help with the lower than usual stocks of silage.” Key to being able to manage the challenges thrown up by the weather and the farm’s location is to keep things flexible, says Sally Lancaster, with the mix of efficient grazing and silage-based TMR suiting them well.

“We like to think we run a fairly extensive system but aiming to provide what is right for the cows is the priority. If the weather is good the cows go out and if it’s not we bring them in. Plus we don’t want to create extra work unless we have to.

 “Grazing and grassland management as the main production system has never been a big thing in this area and we’ve always been in a bit of a minority with what we do. Most people are moving towards a more intensive system, but whatever you’re doing, getting the most out of your home grown forage is critical.”

 Fertiliser needs have come under the spotlight in recent years with independent grassland consultant Dr. George Fisher looking at ways nutrient use can be improved across grazing and silage. To this end, trials were set up last year on the farm to look at the relative efficiencies of Ammonium Nitrate (AN) v. urea and also the implications of using Sulphur more effectively.

 In the first trial, silage yields were analysed using half a 9 acre (3.6ha) field receiving straight Nitrogen in the shape of Nitram (34.5%N) and the other half getting only urea. Both plots received the same 300kg N/ha (240 units/acre) to provide sufficient N for four cuts of silage to be taken. The field that had just been reseeded after wholecrop wheat was selected for the trial as the new ley would be more responsive to N and give a clearer picture of yield differences, George Fisher explains.

 “The Nitram AN outperformed the urea in every cut apart from the final one and overall produced an extra 2.7t DM/ha – 15.8t DM/ha as opposed to 13.1t DM/ha - representing a 21% increase in grass yield compared to the urea treatment. “The 13.1t DM/ha from the urea is pretty impressive in itself so an extra 2.7t/ha just shows what gains there are to be made from choosing a more appropriate Nitrogen source.”

 Much of the difference in performance is due to the varying amounts of N absorbed by the plants after the AN and urea applications, George Fisher says. “The fertiliser was put on at the normal times for first cut taken on the 8th May, second cut on the 15th of June and third cut on the 25th of July.

“Drier weather conditions at the time of applications meant that much of the N in the urea was lost to the atmosphere through volatilisation before it could be taken up by the crop. “Without rain in the three days after application, volatilisation and N loss is significant with urea so plants simply do not receive as much of the N you are applying, whereas the N in AN is available to them immediately.”

 In fact, an analysis of weather conditions for the area showed that of the 31 days in May only 3 had conditions that would have favoured urea, in June this rose to 12 and in July it was 7, he explains. “For the May to July quarter, only 24% of the days last year had conditions that would allow urea to produce a comparable yield response to AN and this is far from unusual in most years.

 “It’s a numbers game really. Urea can be cheaper than AN but there are only a limited number of opportunities where it will perform as well as AN in the UK climate.” In the second trial at the farm, using a combined Nitrogen and Sulphur product CF SingleTop (27N + 12SO3) as opposed to straight Nitrogen for grazing also produced a 0.5t/ha yield advantage, leading Jos to now rethink of his current fertiliser practice.

“We will always use Sulphur on the farm now and there are obvious advantages to an NS True Granular Compound over a blend simply in terms of consistency of product and evenness of spread. “The AN issue is a bit more complex as, like many grassland producers, we’ve always grown up thinking urea is the lowest cost source of N for grassland – especially if you can use it early enough in the season when conditions should reduce the risk of volatilisation.

 A 21% increase in silage yield is difficult to ignore especially in a year when the farm run short of silage, Jos points out. “If we had got anything like this response across the majority of our grassland this last year, we wouldn’t have run out of silage and would have saved much of the £5000/month we’ve had to spend on pressed pulp. “I think we will be using more AN in the future but with the improvement in yields we saw from using Sulphur, however, we would probably move straight to SingleTop rather than Nitram and get the advantages of both the better N and S responses in one product.”

 It’s likely that a return to three cuts of silage from last year’s four is on the cards, too, Jos says. “Theoretically, you should be able to get better silage quality from more cuts, but you also need the bulk of a big first cut too – and we’ve missed that this year. “Plus more cuts means more work and with a small team, it’s not always easy to accommodate the extra cut. But it’s all part of the learning curve and we know making better decisions in a few key areas can make a huge difference to our overall efficiency of production.”

 

Return on Investment 

A nine to one return on investment could be achieved from using AN over urea based on the yield responses at Paradise Farm, says Dr. George Fisher.

Independent grassland specialist Dr. George Fisher.

“The four cuts of silage taken over the 70ha of silage last year had an overall input of 300kg N/ha which could have come from either 652kg urea/ha or 870kg Nitram/ha.

“At £275/t, the urea would have cost £170.30/ha or £12,551 over the 70ha and the Nitram would have cost around £240/t giving £208.80/ha or £14,616 for the full 70ha so that’s a cost saving of £2,065 in favour of urea.”

But with the extra 2.7t DM/ha being the equivalent of 9t freshweight/ha and 30%DM silage being sold at 30/t freshweight, the four cuts taken equate to a £270/ha gain which over the 70ha would be worth £18,900, he explains.

“So for just over £2000 more fertiliser cost, you’re getting the equivalent of an extra £19,000 worth of silage which represents a potential return on investment of over nine to one which is difficult to ignore.”