Text 3. Harrows

Cultivators, which only work to a depth of 6 inches, are called harrows. They consist of four or five rows of either rigid or spring tines mounted on a frame. The number of frames or sets pulled by a tractor will vary with the power of the tractor. Modern harrows are usually attached to the hydraulic lift of the tractor.

Harrows have many effects on the soil during the process of seedbed preparation. Primarily, they break end sort the clods. The fact that the tines on some harrows sink to the depth of the frame also results in a leveling action.

There is a wide range of design and size of harrow and the harrow chosen will vary with the particular task that has to be undertaken. Spike — toothed or zig-zag harrow.

This type of harrow is usually classified according to weight and the length of the tine. Heavy harrows are used in the early stages of seedbed preparation. Where a finer tilth is required, or for harrowing in after sowing, medium, and light harrows are used.

Dutch harrow. This harrow has recently become popular, because its heavy wooden frame gives a level finish to the seedbed, suitable for subsequent precision seeding and thinning.

Spring-tine harrow. This is a very effective tilth producer, as it holds well into the work and the vibrating action of the tine causes clods to shatter. The depth of work may be controlled by land wheel or in some cases by adjustment of the tines,

Weeders⁴⁾. These are в series of closely spaced spring tines for raking the surface, to remove annual weeds by vibrating action.

spike-toothed (zig-zag harrow) - зубовая борона, борона типа "зиг-заг"
dutch harrow - гвоздевая борона

weeder - полольная борона