A disc plow is an essential tillage implement used by farmers to cultivate soil. It consists of a framework carrying one or more gangs (rows) of circular concave steel discs that are inclined backwards.
The discs are typically around 20 to 38 inches in diameter with a concave shape to enable deep tillage.
As the plow is pulled across a field, the discs rotate and cut into the soil, breaking it up and turning it over.
A Brief History of the Disc Plow
Disc plows were invented in the late 1800s and steadily gained popularity in the 1900s. The rotating discs offered an advantage over traditional moldboard plows in certain soil conditions.
The first successful disc plow was designed by James Oliver in 1868.
Over the decades, many improvements were made including the addition of scrapers, better disc materials, and hydraulic control systems.
Manufacturers like John Deere perfected disc plow designs for mass production. Today, disc plows continue to be a versatile and essential tillage tool.
[Related Post: 5 Types Of Plows For Farming]
How Disc Plows Work
The concave discs act almost like circular knives, slicing into the ground at an angle as they turn. This action pulverizes the soil with less resistance compared to flat discs or plow bottoms.
The concave shape also provides a self-sharpening effect as soil abrasion wears down the inner disc edges.
The discs till the soil without completely inverting it. This has the benefit of keeping plant residue on the surface. Having stubble cover after plowing helps prevent wind erosion.
However, the soil is thoroughly loosened and aerated for planting.
Benefits of Disc Plowing
Disc plows offer several advantages over other plow types:
- Cut easily through hard, dry soils where moldboards struggle
- Move more easily through sticky or gumbo soils
- Provide better traction on rough, uneven, or hilly ground
- Can penetrate rocky soils without damage
- Leave protective residue cover on surface
- Allow mounting of attachments for secondary tillage
The lightweight discs also require less draft power from tractors compared to moldboard plows.
When Disc Plows Excel
Disc plows perform exceptionally well in certain soil conditions where other plows falter:
- Hard, baked, or crusty soils: The sharp discs cut through tough surfaces better than moldboards.
- Rocky, uneven terrain: Discs easily work around rocks and slope changes compared to rigid plow bottoms.
- Gumbo and sticky soils: The discs experience less suction and sticking than moldboards when plowing gumbo.
- Areas prone to wind erosion: Discs allow crop residue to remain on the surface for protection.
- Fields with heavy crop residue: Discs can cut through and bury residue better than other plow types.
Disadvantages of Disc Plows
Despite their strengths, disc plows also have some disadvantages:
- Can smear wet soils due to sliding action of discs instead of clean inversion.
- Generally provide shallower tillage depth than moldboard plows.
- Tend to wear down more quickly from abrasion than moldboard plow shares.
- Provide less weed control since weeds are cut off rather than buried.
- Require more precise depth control adjustments than moldboards.
Disc plows have become a versatile, essential tillage tool for farmers across various soil types and field conditions.
Their unique concave disc design offers agronomic advantages that complement and improve upon traditional moldboard plowing.
When utilized properly, disc plows can optimize soil health and prepare ideal seedbeds for planting.