PERISCOPE METHOD FOR OBSERVING ROOT-GROWTH AND DISTRIBUTION IN FIELD SOIL

This paper describes a technique for observing root growth in the field using glass tubes and a periscope. Roots of two crops (winter wheat and millet) were studied in situ with the periscope and the results compared with those obtained from washed soil samples. Generally, both techniques gave similar patterns of growth and distributions of roots although the periscope measurements, when compared with washed soil samples, tended to underestimate root density close to the soil surface and overestimate densities lower in the profile. Both methods allowed differences in the root systems of irrigated and unirrigated crops to be distinguished but the periscope method was considerably faster. © 1979 Oxford University Press.