A disc harrow at Bartley Ranch loop trail

This picture shows a disc harrow, which was once used on the Quilici Ranch near Dayton and is now on display at the Ranch Loop Trail at Bartley Ranch in Reno, Nevada. A walking tour along this trail takes visitors to various farm equipment including a spring tooth harrow and this disc harrow, for which an interpretive panel explains that it is traditionally used after a field had been plowed. It prepares a field for new crop growth by cutting remaining stalks and roots from the previous harvest into the soil and it helps loosening the soil and smoothing the surface. The panel provides the following details:

The [disc] harrow is pulled across the field causing the series of circular concave discs (which are set at opposing angles) to rotate, thereby cutting the remains of the harvest into the soil, replenishing the topsoil as it decays into humus. Depending on the previous crop, this may take several passes. 

Keywords: history, farm equipment, agricultural tillage tool, plowing, interpretive trail.