Parameters for furrow

a. Shape of the furrow: ‘U’, ‘V’ or trapezoidal shape.

b. Depth:

• Depends on soil type and crop size.
• Normally 7.5-12 cm.

c. Furrow spacing:

• Depends upon soil type and crop type.

i) Soil type:

• To obtain complete wetting of sandy soil to the depth of 1-1.5 m, furrows should be spaced more than 50-60 cm apart.

ii) Crop type:

• Crops like potatoes, maize and cotton have furrows between all rows.
• Vegetable crop often have 2 or more rows between furrows.
• Wide spread crop like melons, fruit and berries require more than one furrow between crop rows.

d. Length of furrow:

• 100-200 m
• Depends on soil type, slope, discharge, size and shape of the field.
• Less in coarse textured soil.

e. Slope of furrow:

• Controls the spread of which water flows to furrows.
• 2-5%.
• Minimum slope to ensure drainage in a furrow is 0.05%.

f. Stream size:

• Stream size is limited to 0.5-2.5 %.
• The stream is reduced or outbreak so that it will just keep the furrow wet throughout its length with a minimum water at the end.