The disk tiller (Figure 8.8) is also known as one-way disk plow, vertical-disk plow, harrow plow, and wheatland plow. It is similar to a disk plow in regard to the frame, wheels, and depth control, but the disk tiller blades are uniformly spaced along one axle or gang bolt and clamped together through spacer spools so the entire gang rotates as a unit

Figure 8.8 – A pull-type one-way disk tiller or wheatland plow.

This implement is used in dryland grain-growing regions for shallow tillage (often only 8 to 13 cm) and mixing plant residue with the soil. The soil surface is left rough with visible plant residue to reduce soil erosion. Disk tillers are used for primary tillage and are frequently used in subsequent operations for summer fallowing. Some disk tillers are equipped with seed and fertilizer attachments to accomplish seedbed preparation, seeding, and fertilizing in a single operation.

The blades of a disk tiller are somewhat smaller than those of a standard disk plow, the most common diameters being between 51 and 61 cm. They are generally spaced 20 to 25 cm apart along the gang bolt. The width of cut per blade depends upon the spacing and upon the gang angle (adjustable) between the gang axis and the direction of travel. Gang angles range from 35° to 55°, with 40° to 45° being most common. There is no tilt angle, and the disk angle is commonly between 35° and 55° (disk plow disk angles are 42° to 45°).

Since disk tillers are primarily for relatively shallow tillage, they are built much lighter than disk plows (usually 45 to 90 kg/blade). They are available with integral and drawn hitching configurations. Most disk tillers move the soil only to the right, but reversible models are available which can move the soil in either direction.