Subsoiler

A subsoiler or flat lifter is a piece of agricultural equipment used for deep tillage, loosening and breaking up soil at depths below the levels worked by moldboard ploughs, disc harrows, or rototillers. Most such tools will break up and turn over surface soil to a depth of 15–20 cm (6–8 in), whereas a subsoiler will break up and loosen soil to twice those depths.

A subsoiler should not be confused with a mole plough: an agricultural implement used to create underground drainage channels, a technique known as mole drainage. The subsoiler is a tillage tool which will improve growth in all crops where soil compaction is a problem. In agriculture angled wings are used to lift and shatter the hardpan that builds up due to compaction. The design provides deep tillage, loosening soil deeper than a tiller or plough is capable of reaching. Agricultural subsoilers, according to the Unverferth Company, can disrupt hardpan ground down to 60 cm (24 in) depths. When a field is optimally subsoiled, crops will perform well during hot and dry seasons because roots penetrate soil layers deeper to reach moisture and nutrients. In wet conditions, the water passes more easily through the shattered areas, reducing the possibility of crops drowning.

Agricultural implements that are not powered by human labor typically come in three types: self-propelled, trailed, or mounted. A self-propelled implement has its own drive system. Trailed and mounted implements, on the other hand, require an external power unit, such as a tractor. A trailed implement has its own chassis, while a mounted implement does not and is therefore lifted and lowered by the tractor's hydraulic system. Subsoilers are most commonly found in a mounted configuration. In countries where fields are generally larger, trailed subsoilers are also common. In both cases, a tractor is used as the power source.

• Mounted subsoiler
• Trailed subsoiler