An evaluation and proposed modification of the soil tilth index

Abstract

One of the factors critical to plant germination and development is good tilth. Unfortunately, this factor is often evaluated only subjectively, hence its adequacy depends on the experience of the evaluator rather than on a standard procedure. Quantifying tillage allows energy conservation and optimization by eliminating unnecessary tillage operations that may also aggravate the already fragile environment. Tilth index is a quantitative value used to describe soil conditions that relate to plant growth and water movement, ranging from 0.0 for the worst soil to 1.0 for the best soil as related to crop production. Five parameters, i.e. soil particle uniformity, organic matter content, bulk density, plasticity and cone index, thought to be the most important in determining soil tilth were evaluated for different tillage systems and their effects were combined to calculate the tilth index. The applicability of tilth index to energy conservation and yield prediction is discussed.