A subsoiler or flat lifter is a

tractor A tractor is an engineering vehicle specifically designed to deliver a high tractive effort (or torque) at slow speeds, for the purposes of hauling a Trailer (vehicle), trailer or machinery such as that used in agriculture, mining or constructio ...

-mounted

farm implement Agricultural equipment is any kind of machinery used on a farm to help with farming. The best-known example of this kind is the tractor. Tractor and power *Tractor / Two-wheel tractor * Tracked tractor / Caterpillar tractor Soil cultiv ...

used for deep

tillage Tillage is the agriculture, agricultural preparation of soil by mechanical wikt:agitation#Noun, agitation of various types, such as digging, stirring, and overturning. Examples of manual labour, human-powered tilling methods using hand tools inc ...

, loosening and breaking up

soil Soil, also commonly referred to as earth, is a mixture of organic matter, minerals, gases, water, and organisms that together support the life of plants and soil organisms. Some scientific definitions distinguish dirt from ''soil'' by re ...

at depths below the levels worked by moldboard

plough A plough or ( US) plow (both pronounced ) is a farm tool for loosening or turning the soil before sowing seed or planting. Ploughs were traditionally drawn by oxen and horses but modern ploughs are drawn by tractors. A plough may have a wooden ...

disc harrow A disk harrow is a harrow (tool), harrow whose cutting edges are a row of concave metal discs, which may be scalloped or set at an oblique angle. It is an list of agricultural machinery, agricultural implement that is used to tillage, till the ...

s, or rototillers. Most such tools will break up and turn over surface soil to a depth of , whereas a subsoiler will break up and loosen soil to twice those depths. The subsoiler is a tillage tool which will improve growth in all crops where

soil compaction In geotechnical engineering, soil compaction is the process in which stress applied to a soil causes densification as air is displaced from the pores between the soil grains. When stress is applied that causes densification due to water (or other ...

is a problem. In agriculture angled wings are used to lift and shatter the

hardpan In soil science, agriculture and gardening, hardpan or soil pan is a dense layer of soil, usually found below the uppermost topsoil layer. There are different types of hardpan, all sharing the general characteristic of being a distinct soil layer ...

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 depths. The subsoiler consists of three or more heavy vertical shanks (standards) mounted on a toolbar or frame with shear bolts. They can be operated at depths of or more. A ripper normally runs deep. Shanks are curved and have replaceable tips. Each shank is fitted with a replaceable point or foot, similar to a chisel plough, to break through the impervious layer, shattering the sub-soil to a depth of . Subsoiling is a slow operation and requires high power input: to pull a single subsoil point through a hard soil. Typically, a subsoiler mounted on a compact utility tractor will reach depths of about and have only one thin blade with a sharpened tip. The shanks should be inclined to the vertical at an angle greater than 25-30 degrees, preferably 45 degrees, and it is advisable that the height be adjustable. The points of the shanks are normally about wide and should be easy to replace. The condition of the points is very important: often the subsoiler fails to give good results due to the condition of its points. Points can be fitted with horizontal wings, about wide, which considerably increases the width of soil below ploughing depth loosened by the subsoiler. These plows are sometimes equipped with a torpedo-shaped attachment for making subsurface drainage channels. The subsoilers are raised and lowered hydraulically. Some models feature power-take-off (PTO)-driven vibrating devices. The typical spacing is between shanks. Shanks should be able to reach below the deepest compacted layer. Shank spacing and height should be adjustable in the field. Towed subsoilers should have gauge wheels to control the shank's depth. Shanks usually are from thick. Thinner shanks are suited for agricultural use. Thicker shanks hold up better in rocky conditions, but require larger, more powerful equipment to pull them and disturb the surface more. Various manufacturers' brochures claim that crops perform well during hot and dry seasons because roots penetrate soil layers deeper to reach moisture and nutrients. Brochures further claim that in wet conditions, the water passes more easily through the shattered areas, reducing the possibility of crops drowning. Agricultural subsoiler implements will have multiple deeper-reaching blades; each blade is called a scarifier or shank.

Purdue University Purdue University is a Public university#United States, public Land-grant university, land-grant research university in West Lafayette, Indiana, United States, and the flagship campus of the Purdue University system. The university was founded ...

's Department of Agriculture indicates that common subsoilers for agricultural use are available with three, five or seven shanks. Subsoilers can be up to wide; some models are towed behind tractors while others are mounted to the three-point hitch.Purdue Ag Equipment Sizes & Storage
One type of subsoiler has a torpedo-shaped tip and is called a mole plough because the tip describes a path much like the

burrow file:Chipmunk-burrow (exits).jpg, An eastern chipmunk at the entrance of its burrow A burrow is a hole or tunnel excavated into the ground by an animal to construct a space suitable for habitation or temporary refuge, or as a byproduct of Animal lo ...

that a mole creates. Mole ploughs are used to create

tile drainage Tile drainage is a form of agricultural drainage system that removes excess sub-surface water from fields to allow sufficient air space within the soil, proper cultivation, and access by heavy machinery to tend and harvest crops. While surface wa ...

, with or without tiles or tile line added. A form of this implement (with a single blade), a pipe-and-cable-laying plough, is used to lay buried cables or pipes, without the need to dig a deep trench and re-fill it.

References

{{reflist Agricultural machinery

See also

References