Home Subsoilers and how to use them
Carrfields has added the Grange range of soil-loosening equipment to its portfolio of crop and pasture establishment tools.
British farmer and engineer Rhun Jones established Grange Machinery specifically to produce conditioning tools to manage sub-surface soil damage. His company has quickly grown to become one of the UK's leading machinery manufacturers, well-known for its innovation.
Sub-surface soil damage, by its very nature, is difficult to see and its effects are often poorly understood or only identified when it is too late. Usually, this is later in the season when cropped soil or grassland is lying very wet.
Also, as larger equipment and heavier tractors have been progressively employed over the past 30 years, sub-surface damage from soil compaction has been hidden from view.
The type of tyres used on farm machinery, operating pressures, the timing of field operations, weather, and of course soil type, all have a significant effect on subsurface soil damage.
With the use of some basic technology and a bit of physical exercise it is not hard to identify and then rectify or prevent compaction.
When compaction or drainage issues are suspected, it is important to identify whether you have micro or macro drainage issues. The first step is to pick up a very simple and often neglected tool – the spade. Dig some holes and look at your soil composition.
The Carrfields team can help with visual soil assessment and can use a slightly more sophisticated tool, a penetrometer, to help identify any compaction layers.
When it comes to micro-drainage, soil structure is the key. Look for a nice crumb structure throughout the profile.
Macro-drainage combines two elements: 1) Letting water infiltrate into the lower soil profile, and 2) Moving water away from the lower soil profile.
If the upper soil profile is well structured but infiltration to the lower profile is hindered by a compacted layer, then ponding will occur. Subsoiling may alleviate the problem, but first, the spade (or penetrometer) must be used to identify if there is a compacted layer and, if so, at what depth.
This is critical. Don’t be tempted to run the subsoiler too deep. In some heavy soils, this may make the problem worse by causing upward compaction if the ground is too wet.
The idea of upward compaction may sound strange because this type of damage appears to be at odds with the effect of weight from tractors or heavy machinery. Subsoiling will only be effective if the deep sub-surface is porous (e.g., with gravel or sand) and the soil above it is dry enough to crack or fissure to allow root growth and water movement.
If your upper soil profile is well structured and there is no compaction layer, but your subsoil is not porous (e.g., if it is clay), then subsoiling will only ‘increase the size of the sponge’.
In this case, subsoiling might improve short-term the amount of water the soil will absorb, but it will still become waterlogged after high rainfall. In this case, you can move excess soil moisture away with macro-drainage, either sub-surface (mole drains, tile/pipe) or surface drainage.
Timing is crucial. Subsoiling and mole ploughing differ in their optimal timing.
Subsoiling should be done when the upper surface layers are dry enough to create cracks radiating out from the point and wing of the subsoiler leg.
On the other hand, mole ploughing should ideally be done in damp subsoil clay that then gets baked to a long-term mole channel in the following dry conditions.
Late spring will normally provide the best conditions for mole ploughing whereas there is more time flexibility with subsoiling.
Of course, the efficacy of subsoil macro-drainage relies on micro-drainage (good soil structure) to work. Both must go hand-in-hand.
If our future weather patterns are going to be more variable, then managing our soils to retain moisture more effectively in dry conditions and remove it wet conditions will have a major impact on the resilience of our farming systems.
Grange range
Grange Machinery is made by and for farmers. The company takes its name from the Jones family’s farm at Sproatley Grange in East Yorkshire.
It offers a range of soil-loosening tools that can be used on their own or in combination with other tillage or seeding machines.
The most effective way to use them is to identify and address the problem when the soil is dry and friable. This often aligns when seeding or preparing a seedbed, and therefore it can be combined with a drill or cultivator as a one-pass system.
Grange machines are designed to loosen soil only at the depth whilst minimising surface disturbance. This makes them well suited for use in combination with min-till and no-till systems.
The Grange Close Coupled Toolbar (CCT) and Low Disturbance Toolbar (LDT) are ideally suited to complement a min-till or no-till drill.
A more traditional subsoiling option is the Grange Low Disturbance Loosener (LDL) and Grassland Loosener (GLL) are designed to operate as independent tools to renovate soil that has been damaged, for example, by winter pugging from livestock.
The LDL and GLL can be fitted with a pneumatic or spinning disc seed applicator, and with a smooth or toothed packer roller. Both machines are the ideal tool for restoring grassland or establishing a cover crop in stubble.
So if you think compaction is an issue on your farm, it is time to get out the spade. Then, if the conditions are right, reach for your Grange subsoiler.
Check out this article as it was featured in Rural Contractor and Large Scale Farmer here.