Harrow (tool)

A harrow is an agricultural implement used to till and smooth the surface of the soil. It is generally used to break up clumps of soil and provide a finer finish, making it suitable for seeding or planting. Harrows differ from plows, which are used for deeper tillage. Harrows are often drawn by tractors or, historically, by animals.

Harrows serve several purposes in soil preparation:

• Breaking up clods: They break down large clumps of soil created by plowing or natural processes.
• Smoothing the soil: They create a level and even surface for planting.
• Incorporating residue: They can incorporate crop residue or fertilizer into the soil.
• Controlling weeds: They can uproot or bury small weeds, especially in early stages of growth.
• Covering seeds: After seeding, they can lightly cover the seeds with soil to improve germination.

There are several types of harrows, each suited for different purposes and soil conditions:

• Chain harrows: These are flexible harrows consisting of a chain mesh with teeth or tines. They are often used for light harrowing and spreading materials.
• Spike-tooth harrows: These consist of rows of rigid teeth that penetrate the soil. They are effective for breaking up clods and smoothing the soil surface.
• Disc harrows: These use rotating discs to cut and till the soil. They are more aggressive than spike-tooth harrows and can be used to break up heavier soils.
• Power harrows: These are powered by the tractor's power take-off (PTO) and use rotating tines or blades to pulverize the soil. They provide a fine tilth and are often used in seedbed preparation.
• Spring-tooth harrows: These have flexible teeth mounted on springs, allowing them to vibrate and break up the soil. They are effective in rocky or uneven terrain.

The choice of harrow depends on the soil type, the desired tilth, and the type of crop being planted. Proper use of a harrow can significantly improve crop yields by creating a favorable seedbed and promoting healthy plant growth.