Volume 55 No 2 April 2007 - New Zealand Society of Soil Science

heralded the beginning of soil survey in what was to subsequently become the Department of
Scientific and Industrial Research (DSIR).
Reorganization of science to form the DSIR
Government science was reorganized in 1926, with Dr Ernest Marsden appointed Secretary to the
Council and Department of Scientific and Industrial Research (DSIR). The Geological Survey and
Dominion Laboratory were incorporated into the new department but Astons laboratory remained in
the Department of Agriculture. Rigg who was a Council member between 1926 and 1954, facilitated
collaboration between the Cawthron Institute and the early soil surveys undertaken by geologists of
the DSIR Geological Survey Division.
Introducing a new soil paradigm
Rigg attended the First International Soil Congress in Washington in 1927, and returned to New
Zealand with new insights into soil classification based on the climate, geology, texture and chemical
composition. He emphasized that the soil profile should be examined and recorded to the depth of the
parent rock. Prior to this, the soil was commonly regarded as only the organic darkened surface A
horizon. By 1906, soil surveyors in the United States had a procedure for finding and mapping soil
boundaries that required a large number of systematic borings using a soil auger, with interpolation
between locations. This was refined and by 1914 instructions acknowledged that soil surveyors might
use landscape features to map soils, in addition to the knowledge of vegetation, parent material and the
climate. In his 1928 report on the Soil Congress, Rigg described the Russian concept of soil zonality
as expressed in Professor K. D. Glinka’s concept of soil geography, a development of the earlier
Russian studies of Professor V. V. Dokuchaev. Dr Marbut introduced these ideas into the United
States cooperative soil survey between 1916 and 1920, and in 1927 published an English translation of
Professor Glinka’s German text, making it more widely available. The arrival of this book in New
Zealand created a paradigm shift, setting Grange and Taylor along a new pathway of soil
investigation. No longer were soils the single unchanging product of a geological substrate but were
over time modified by weathering and leaching processes under the influence of climate and the biota.
Hans Jennys Factors of Soil Formation created a similar impact when it was published in 1941.
Extending the reconnaissance
In 1930 the Council of DSIR asked Rigg, Grange and Taylor to undertake a reconnaissance soil survey
of the volcanic areas of the central North Island with the purpose of identifying the relationship
between soil conditions and bush sickness. Analysis of soil samples was done at the Cawthron
Institute, being the only suitable laboratory at the time, under the direction of Rigg with the assistance
of A. R. Sim and L. Hodgson, and after 1931 Elsa B. Kidson. In 1933 Dr J. Keith Dixon was in charge
of this laboratory with assistants A.C. Harris, Alan. J. Metson and J. T. Corder. Dr Dixon, Metson and
Kidson were seconded from the DSIR. The earlier reconnaissance soil survey had identified soils
formed on eight distinct volcanic ash showers and confirmed the incidence of bush sickness on soils
developed in the Taupo and Kaharoa ash showers, and in a related study on the more strongly leached
soils formed on the (composite) Mairoa ash shower. It was apparent that in the weakly-weathered
Taupo and Kaharoa ashes the incidence of bush sickness was related to the initial properties of the
parent material whereas, in the more leached Mairoa ashes it was more likely to be induced by soil
processes of weathering and leaching under the influence of a high rainfall. This was a big step
forward, as it recognized soil-forming processes leading to the development and differentiation soils.
Correcting cobalt deficiency in soils
Following studies in south Australia on animal ailments, it was realized that bush sickness was caused
by a cobalt deficiency. A palliative treatment with limonite was successful, because of the presence of
trace amounts of cobalt. Dr Henry O. Askew and Rigg investigated similar symptoms to bush sickness
in animals at Glenhope near Nelson and related it to soils developed on weathered granite. A similar
ailment named Morton Mains disease in Southland was associated with leached soils formed in loess.
In the late 1930s Drs Askew and Dixon demonstrated that Glenhope and Morton Mains diseases were
also caused by a deficiency of cobalt in pastures and soils. These early soil surveys played a key role
in the investigations of bush sickness and related diseases and subsequently in the identification of
other mineral deficiencies in soils.
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