LPM 121: Fodder Production and Grassland Management (1+1)

HARROWS

Harrows

• Harrows are used to break the clods, to stir the soil and to destroy weeds after ploughing.

Type of harrows

• Disc harrows
• Spike tooth harrow
• Spring tooth harrow
• Triangular harrow
• Blade harrow
• Power harrow
• Disc harrow is a tractor drawn secondary tillage implement which has concave steel discs of 400 to 600 mm diameter mounted on long gang bolts. The discs are spaced at a distance of 150 to 250 mm by means of spacers. Each disc is provided with a scraper to remove soil sticking to the disc. Cut-away or notched discs are provided in the front gang to cut the crop residues in the field. Disc angle of the discs in a disc harrow is less than 25^º.
• The angle between gang bolt and the direction of travel is called gang angle. Width of operation by the disc harrow is changed by altering the gang angle. The center line of the implement is offset to the center line of the tractor and therefore it is called offset disc harrow. Two gangs are provided one behind the other. The discs in the front gang and rear gang face opposite direction. The offset disc harrow is suitable for tilling orchards.