The implements used for secondary tillage are the peg tooth harrow, disc harrow, tined cultivator, rotary tiller, and inter row cultivators.
Peg tooth harrow
Peg tooth harrows are widely used in animal and 2-wheel tractor powered systems for second workings, soil puddling and land leveling. The width of harrow depends on the number of animals and size of tractor engine but range in size from 1-2m depending on soil conditions. The teeth or pegs in the harrow can be made from wood but more modern versions use steel. The degree of aggression is determined by the angle of operation. The more upright the harrow the more aggressive is the action.
Spike tooth harrow for hand tractor
Disc cultivators are used with 4-wheel tractors and are made up of either 2 or 4 gangs of discs. The discs are smaller than on a one-way or offset plough and the machine is much lighter. The degree of aggression is determined by the gang angle relative to the forward travel. These implements are normally used in dry fields. The disc cultivator can be either 3-point linkage mounted or a trailing version.
The very aggressive action of the plough gives good weed control and cuts and buries crop residues. This plough is also widely used in upland situations.
Three-point linkage mounted
Tined cultivators are very versatile implements as they can be used for secondary tillage and modified to be used as a seed drill. Tine cultivator are used only in dry working situations as they cut the soil rather than invert the soil and kill weeds by cutting and lifting the weeds to the surface. Sweeps range from 50mm to 200mm in width. These cultivators are used where residues need to be left on the surface. Tine cultivators have lower power requirements than disc cultivators and used with animals and 4-wheel tractors. These ploughs can be configured as 3-point linkage mounted or as trailing versions.
Rotovators are commonly used for secondary workings and especially seedbed preparation. They are used with 2-wheel and 4-wheel tractors in both upland and flooded fields. Rotovators have a very aggressive action, which pulverizes the soil and buries weeds and crop residues. In some flooded situations rotovators are used for primary tillage.
Rotary tiller - rotavator