Quantitative Study of Root Systems in Different Soil Types

Abstract

A trench 4-5 ft. long by 3 ft. wide by 4-6 ft. deep is dug immediately beside sample of grass to be studied, the wall next to the sample being made exactly vertical. By careful cutting a sample of soil with the roots of plant intact is transferred from the vertical wall of trench to a long shallow wooden box 12 in. wide, 3 in. deep and long enough to take the total length of roots. The box has only one side and lacks a top, and is driven into the wall around the roots. The box with the sample of soil and included roots in their natural position is transferred to the laboratory where the soil profile is analyzed and recorded and the soil is washed away from the roots in situ by gentle washings with frequent soaking. Cleaned root systems are photographed and sections corresponding to the various soil strata are analyzed, separated, dried, and weighed. Typical samples are described.