Abstract
This paper describes gilgai complexes associated with Black Earths (Stace et al., 1968) in eastern Australia and records some of the observed variation in both native plants and crops growing on these soils. It provides an example of the variation that occurs when only two components of gilgai micro-relief are present and the soils of both are cracking clays. Greater variation is associated with gilgai in other soil groups which have wider contrasts in the characteristics of soils making up the complex. The data used here are drawn mainly from eight pairs of soil profiles from adjacent mounds and depressions in virgin grassland (Reeve et al., 1960; Stace et al., 1968) and from measurements and observations made over several years on the Darling Downs, Queensland (Thompson and Beckmann, 1959; Beckmann and Thompson, 1960; Beckmann et al., 1971; Beckmann et al., 1973).
