13 minute read
Making the most of cover crops and learning their limitations
Clifton farms director, Alan Clifton-Holt was originally looking to cover cropping to address a multitude of issues across his Kent rotation. A decade on from rst introducing them into what is now a 1,520ha arable farm, he has a far better idea of what is now a 1,520ha arable farm, he has a far better idea of what they can do and how to make the most of them.
“Obviously, cover crops haven’t answered every question,” Mr CliftonHolt says. “They certainly have a good place, but there are limitations.
“Their main value to us is that they assist in developing a soil structure into which we can drill spring crops sensibly, and for the extra nutrients they can provide to the next crop.”
Parts of the farm, especially on Romney Marsh, are high pressure for black-grass. Back in the mid-2000s, Mr Clifton-Holt recalls that some elds became almost unfarmable, with blackgrass reducing wheat yields to only 5t/ha.
“We haven’t completely conquered this challenge yet, but we are getting on top of it, having taken some big decisions,” he explains. “These included reducing cultivation passes and depth, incorporating grass leys, sprayingoff badly infested crops and spring off badly infested crops and spring cropping. cropping. “All the things that “All the things that everyone now talks everyone now talks about to combat about to combat black-grass are black-grass are definitely the way definitely the way to tackle it. We’re to tackle it. We’re glad we took glad we took those decisions those decisions early on.” early on.”
Spring cropping for black-grass control
Spring cropping remains integral to current control tactics, with a double spring crop break within a six-year rotation that also includes two winter wheats, winter barley and oilseed rape.
Surprisingly perhaps, spring barley is not a favoured option. Spring oats and spring beans have become the mainstays and cover crops grown ahead of all the plantings.
“With spring crops, there are three over-wintering options,” Mr Clifton-Holt says. “Leave the ground as a stubble, cultivate it, or plant something that can be drilled into. We took the view that the latter option had to be the best way, and it’s working well for us.”
Any cultivations the ground requires are carried out immediately after harvesting each autumn, and the cover crop drilled as soon as possible after that. The aim is August, but it can be as late as late September, depending on weather and workloads, he admits.
Fine-tuned mixes
In recent seasons, the species mix and agronomy of the covers has
Strength – Reliabilty – Quality AgriSolutions
Special off ers
Ex-Demo – £16,000 Stock – £17,000
• Ultimate Minimum-tillage tool for 170hp+ • Subsoil up to 12 inches (300mm) working depth • On-the-go hydraulic adjustment • On farm for £19,500 • Stock items available at further discounts
Call direct for best pricing Andrew: 07967 300 578 Office: 01805 603 363 www.pfc-eu.com
• 3-metre Disc Combination • Active side screens • 560mm discs with NSK sealed bearings •
• Tool bar • Sprung auto reset • Lifting or low disturbance points • Category 3 hydraulic linkage for on-the-go depth adjustment
been ne-tuned with the help of the latest research and on-farm trials overseen by Agrii agronomist, Neil Harper. Drilling large 0.3ha plots of individual species and mixes has been very helpful in providing the best insights here.
“Our best mix to date has been based on rye, phacelia and linseed,” reports Mr Clifton-Holt. “We prefer rye to oats because it’s more prostrate. Oats can be a bit oppy and hold more water, making the eld wetter when you come to drill it.
“Phacelia is a great plant – everyone should be growing it. While linseed does a really good job of soil structuring and soil improvement if you handle it right.”
Following recent trialling with Agrii, the base mix has been tweaked to include a vetch. And buckwheat is also being explored to see whether its phosphate mining ability will help – especially at current prices.
“I was initially reluctant to include vetch, but Neil showed me good evidence there wasn’t any carryover from nematodes or pests that will a ect our pulse crops. One of the reasons we took him on four years ago was to access to this sort of wellresearched support. So, we’ve chosen to run with it.”
Two minds over value of sheep
Overwinter management di ers depending on the following spring crop. Covers ahead of spring oats are grazed into January and February with a ying ock of sheep, before being sprayed o with glyphosate pre-drilling.
Mr Clifton-Holt is in two minds about the value of the sheep here. “The head is telling us it’s the right thing to do, but we’re not yet totally convinced,” he admits.
“We’re seeing some surface compaction following the sheep grazing,” Mr Harper points out. “It’s not that they’re being left on the ground too long, but more a matter of soil type. A high silt content means the surface can cap badly if put under pressure when it’s wet. In which case we’ve found spring cereal yields su er where we direct drill rather than cultivating.
“People might argue that this is because of the cover crop. But we want the cover crop because it’s doing the right thing for our soils and holding nutrients. We are trying to be exible with what we do to make the system work.”
As a result, a light spring tine cultivation now routinely precedes spring oat drilling with a Vaderstad Rapid to remove any shallow compaction. This has improved spring oat performance noticeably.
Without sheep grazing, covers before the spring beans are typically sprayed-o with glyphosate around Christmas to reduce the vegetation. With a surprising amount of regrowth in the base and blackgrass, they are usually sprayed again a week before direct drilling with the farm’s Amazone Cayena.
Increased yields
Yields of the spring beans have de nitely increased since using the cover crop. “They’re running up to around 5–5.5t/ha and they’re certainly more stable,” Mr Clifton-Holt reports. “We don’t have the variability we used to have. I wouldn’t grow beans without them now.
“As we’ve only ever grown spring oats after covers, we don’t know how much they actually contribute to the crop’s performance. Having said that, we’re happy with the 7–7.5t/ ha the oats deliver. And, as they’re on a contract at a decent price, the numbers add up.” FG
Vetch.
For the perfect seed placement - let’s get straight to the point
They say size isn’t everything, but the
Condor direct tine seeder, in 12 and 15 metres, ticks both the size and the flexibility boxes. The 8,000 litre seed hopper, which is carried on the tractor link arms to ensure plenty of traction, is split into 3 - enabling up to three different seed varieties or a mixture of seed and fertiliser to be drilled simultaneously - and all from vari-rate maps.
With up to 200 kg of coulter pressure, the
ConTeC pro chisel opener ensures a residue-free seed groove with the seed being embedded into the furrow by the following press wheel on each coulter. It couldn’t be simpler, it couldn’t be more effective and above all it helps you love your soil.
The ConTeC pro opener ensures the perfect seed placement.
Liquid fertiliser o ers sustainable farming future
In the last 30 years, D S King and Sons, farming in Bourne in Lincolnshire, has adapted its business to keep pace with an increasingly challenging industry, while helping to secure a sustainable farming future. pace with an increasingly challenging industry, while helping to secure a sustainable farming future.
The business currently runs to 688ha of tenanted and contract farmed land and supports a rotation based on milling, feed and seed quality wheat, winter feed barley, OSR, winter beans, linseed and spring oats. Wheat is grown on a two-year rotation and yields average 9.5t/ha.
“Liquid rather than granular fertiliser has been used on the farm for decades due to its improved accuracy, better environmental pro le, convenience and better health and safety implications compared to a granular fertiliser alternative,” says Daniel King (pictured). “It has had a huge impact on our business performance over the years.”
Omex liquid fertilisers are delivered from Bardney in Lincolnshire and pumped directly into the farm’s two strategicallypositioned 50t bunded tanks.
“A key advantage of liquid fertiliser is that there is no risk to our employees unloading heavy bags or lling the spreader,” he says. “We also don’t have to worry about storing bags under cover, which frees up valuable space for crops and machinery.
“Granular fertiliser can be applied up to 24m but there is always going to be over and under lapping, especially on the headlands,” he explains. “With all farmers now having to be more environmentally aware, liquid fertiliser ts the pro le perfectly and in my opinion is really the only option for farming’s future.”
He adds that with a liquid system being so much more accurate, it presents an excellent opportunity to reduce inputs without compromising yield and quality. If you’re thinking of moving to a liquid fertiliser system, speak to liquid fertiliser expert Omex. FG
NitroShield
UREASE INHIBITOR
Protecting your nitrogen Improves Nitrogen Use Efficiency Reduces ammonia losses by 70%+
Contact us today 01526 396000
Visit www.omex.com Email agriculture@omex.com
AHDB issues Soil Health Scorecard guidance
Soil health has been broken down into measurable parts to help farmers optimise productivity. Dr Amanda Bennett, AHDB senior environment manager, explains.
Soils are the foundation of agriculture, providing a range of ‘ecosystem services’, helping to regulate climate and water, sequester carbon, and cycle nutrients. It is important that soils are managed appropriately to deliver these functions. Yet, their inherent properties (soil type and geological history) and site-speci c management mean each eld’s soil has its own unique ngerprint.
Cultivations, drainage, inputs, rotation, and cropping sequence all impact a soil’s physical, chemical, and biological make-up, meaning that what works in one eld may fail to work the same way in another. However, to optimise soil health, you need to measure it rst.
Soil health indicators
The levy-funded Soil Biology and Soil Health Partnership developed and validated a set of practical indicators for the routine measurement and monitoring of soil health: • Visual evaluation of soil structure (VESS) • pH • Extractable nutrients (P, K, Mg) • Soil organic matter • Earthworms • Measures of microbial activity. The researchers worked with farmers, industry and scientists, to develop a robust, simple, and visual framework – the Soil Health Scorecard – to group these soil health indicators.
Although putting the indicators in one place was a great step, it is the inclusion of benchmark values that o ers a potential revelation for soil management. For each indicator, the partnership identi ed ‘typical’ benchmark values (expected ranges for UK soil types and climate regions). The scorecard exploits these values to grade the results of site-speci c soil analyses using a tra c light code:
Green (monitor): Typical or optimum result, with low risk of sub-optimal soil conditions (continue to monitor on a rotational basis)
Amber (review): Moderate risk of sub-optimal soil conditions (further examination, such as more frequent or detailed sampling, may be needed)
Red (investigate): Potential risk of sub-optimal soil conditions (more immediate management intervention may be required).
Soil health guidance
The Soil Health Scorecard is a simple way to generate soil health data. However, for it to be e ective, it is essential to follow sound soil sampling and analysis approaches.
The AHDB Cereals & Oilseeds YouTube account features a ‘how-to’ eld demonstration video, delivered by NIAB’s Elizabeth Stockdale. The guidance document also details the benchmark values for the physical, chemical, and biological soil health indicators. Importantly, the guidance highlights management recommendations for the current tra c light soil condition – to help you maintain or improve your soils.
This structured way to evaluate soils is also useful if you want to assess changes to soil management. For example, if you plan to change your cultivation technique, simply complete the Soil Health Scorecard rst. Subsequent analyses will provide valuable insight into how soil condition has been a ected, allowing you to make more informed decisions to bene t your farm business. FG
Field name (soil texture)
70 Acres (medium stony) Old Park (light silt stony)
Rye Furlong (medium stony) Typhrees (medium)
SOM (%) 4.2 (CM) 4 (CM) 3.9 (R) 3.7 (R)
pH 8.2 (R) 7.5 (R) 8 (R) 7.6 (R)
Ext. P (mg/L) 37 (CM) 48 (R) 56 (R) 28 (CM)
Ext. K (mg/L) 125 (CM) 151 (CM) 186 (CM) 97 (R)
Ext. Mg (mg/L) 28 (R) 47 (R) 32 (R) 29 (R)
PMN (mg/kg) 43 (CM) 107 (CM) 46 (CM) 99 (CM)
CO2-burst (mg/kg 66 (I) 159 (CM) 71 (I) 148 (CM)
VESS 2 (CM) 1 (CM) 1 (CM) 3 (R)
Earthworms (number/pit) 13 (CM) 12 (CM) 8 (CM) 29 (CM)
AHDB Soil Health Scorecard example (Source: AHDB).
For when you want to drive down establishment costs and improve soil health…
LOVEYOURSOIL
…but don’t want to compromise on yield.
With 20 years’ direct strip-till experience, we know that Claydon drilling is good for your soil and good for your pocket. It dramatically reduces fuel consumption, doesn’t require huge horsepower to pull, aids carbon sequestration and reduces soil erosion. Worms just love it. And importantly, yields are healthy too.
