Recommend in light soils and in rocky fields to control soil movenemnt. In rocky conditions, they reduce stress loads on the frame and gang components. In other soil types, especially with 7-1/4" to 9" blade spacing, concave blades also may be your choice for general purpose disking and chemical incorporation.
JOHN DEERE DESIGN - CONE STYLE
Recommended for medium and heavy soils for more aggressive cutting and mixing action. May also penetrate better than spherical blades.
CASE-IH DESIGN - FLAT CENTER
Offered as a replacement for OEM blade. Same cutting and soil movement action as a normal concace disc.
MILLER (NEW HOLLAND) DESIGN SPECIAL
Offered as a replacement for OEM blade. These blades feature a special shallow concavity.
Recommended for most tillage applications.
Improves penetration in hard ground and slicing action in heavy residue.
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