J. Roger Bray and Gwendolyn Struik

The Diverse Contributions of J. Roger Bray and Gwendolyn Struik
by Orie Loucks, submitted December 23, 2010
J. Roger Bray, through post-PhD collaboration with his former doctoral adviser at Wisconsin, John Curtis, was the lead author of one of the most significant post-war papers in the field of ecology (Bray and Curtis 1957, see Beals 1984). It presented a way of seeing the vegetation of a region quantitatively and three-dimensionally. The paper took a major step toward ending the view held by some scientists that vegetation is a collection of distinct associations, and instead advanced the principle of continuous variation, a view that over the next 20 years came to be accepted around the world.
Roger Bray was born in Belleville, Illinois, in 1929 and grew up in Urbana. His father was a soil chemist widely known for having established the Bray Test for available soil phosphorus. Roger was active in a Congregational Church youth group whose pastor was a pacifist, creating a significant anti-war environment. He also showed an early love of learning and a determined scientific curiosity, and finished his undergraduate work in 1950, with honors in Botany, after three years at the University of Illinois. In August 1950, Roger was accepted as a graduate teaching assistant under John Curtis at the University of Wisconsin (Madison) and began field work on Wisconsin savanna composition and the mutual occurrence of plant species (Bray 1956).
In 1951 Roger received the Botany Department Fellowship and wrote a dissertation in two parts—the phytosociology of Wisconsin’s savanna (Bray 1960) and the influence of the concepts of order and complexity as alternatives to the prevailing ecologic mechanism (Bray 1958). In autumn 1955, Roger went to the University of Minnesota where he taught ecology and worked with Don Lawrence on a study funded by a substantial long-term Hill Foundation grant. That work resulted over the following years in reports on plant productivity and energy balances (Bray et al, 1959, 1960, 1961, 1962, 1966).
After two years at Minnesota, Roger became an Assistant Professor at the University of Toronto, which continued from 1957 to 1962. During this time he extended his summer research at Minnesota, started a forest litter study that grew into a world-wide synthesis of litter production (Bray and Gorham 1964), and published his first climatology paper on a statistical examination of the change in atmospheric CO2 from 1873 to 1955 (Bray 1959).
At Toronto, Roger, together with Dr. Michael McNamee, a nuclear physicist who had worked in London with Bertrand Russell on nuclear disarmament, founded the Canadian Committee of 100. Along with the Toronto Faculty Committee for Nuclear Disarmament, the group put pressure on the Canadian government to oppose all nuclear bomb testing.
During these years Gwendolyn J. Struik, born in 1932, graduated from Antioch College and came to study under John Curtis. She and Roger married in 1961, after she finished her PhD in 1960 and was teaching at Wheaton College, Massachusetts. Roger recognized her sharp mind for ecology, as well as the influence of her father, a famous Dutch mathematician and Marx scholar at MIT. Gwen’s research was on the integration of understory components in Wisconsin forests, the next phase of the Curtis plan for plant ecology in Wisconsin (Struik 1965).
In 1962 Roger resigned at Toronto, protesting Canada’s allowing US nuclear weapons in Frobisher Bay in the Canadian Arctic. In late 1962 Roger and Gwen moved to Kelowna, British Columbia, with a study grant from the AAAS. They were there less than a year when the “Cuban nuclear crisis” occurred and they moved to New Zealand with jobs at the Department of Scientific and Industrial Research (DSIR), Palmerston North. Gwen worked on the autecology of flatweeds in various grasslands, and Roger worked fulltime on climatology, beginning with a study of Caesium-137 in NZ milk (Bray & Jackman, 1968).
After fulfilling their travel bond, Roger and Gwen moved to Nelson where Roger published 23 papers on solar climate relationships and the effects of volcanism on climate, of which 14 appeared in Nature or Science. He also completed a review of vegetation distribution, tree growth, and crop success relative to recent climate change (Bray 1971). In Nelson, Gwen ran for parliament for the NZ Values Party (now the Green Party) in 1975 and 1976 and they both worked for a nuclear-free NZ, which was enacted into law in 1987. They also helped found the first NZ coastal conservation group in 1973, which is still active in 2010. Gwen later published on NZ fisheries (Struik 1983).
In 1970, Roger and Gwen bought a property adjacent to a coastal forest and have since produced much of their food, raised three daughters, sampled their mature and regenerating forests, trapped more than 1000 brush-tailed Australian possum pests, and for nearly 40 years have set the same fish net in the same location in a nearby estuary (Bray and Struik 2006).
A summary of Roger’s contributions to plant ecology (through some 70 papers) is in McCune and Beal’s 1993 paper on the History of the Development of the Bray-Curtis Ordination. Despite leaving the upper Midwest, the site of his most famous scientific contribution, the number of his high citation papers among Curtis and students is tied for second (with Loucks) after only Curtis himself (Table 4, p 188, Mladenoff and Burgess 1993). Bray’s impact will be long remembered.


Bray. J.R. and J.T. Curtis. 1957. An ordination of the upland forest communities of southern Wisconsin. Ecol. Monogr. 27:325-349.
Beals, E.W. 1984. Bray-Curtis ordination. An effective strategy for analysis of multivariate ecological data. Adv. Ecol. Res. 14:1-55.
Bray, J.R., 1960. The composition of savanna vegetation in Wisconsin. Ecology. 41: 785-790.
……., 1956. A study of mutual occurrence of plant species. Ecology 37: 21-28.
……., 1958. Notes toward an ecologic theory. Ecology 39: 770-776.
…….., D.B. Lawrence and L.C. Pearson. 1959. Primary production in some Minnesota terrestrial communities for 1957. Oikos 10: 38-49.
…….., 1960. The chlorophyll content of some native and managed plant communities in central Minnesota. Can. J. Bot. 38: 313-333.
……., 1961. Measurement of leaf utilization as an Index of Minimum Level of Primary Consumption. Oikos 12: 70-74.
……., 1962. Estimates of energy budgets for a Typha (cattail) marsh. Science 136: 1119-1120.
……., J.E. Sanger and A.L. Archer 1966. The visible albedo of surfaces in central Minnesota. Ecology 47: 524-531.
……., and E. Gorham. 1964. Litter production in forests of the world. Adv. Ecol. Res. 2: 101-157.
……., 1959. An analysis of the possible recent change in atmospheric carbon dioxide concentration. Tellus 11: 220-230.
Struik, G., 1965. Growth patterns of some native annual and perennial herbs in southern Wisconsin. Ecology 46: 401-420.
Bray, J.R. and R.H. Jackman. 1968. Soil and climatic factors related to Caesium-137 content in New Zealand milk. N.Z.J. Science. 11:352-362.
……., 1971. Vegetational distribution, tree growth and crop success in relation to recent climatic change. Adv. Ecol. Res. 7:; 177-233.
Struik, G.J. 1983. Commercial fishing in New Zealand. The Ecologist 13:213-221.
Bray, J.R. and G.J. Struik. 2006. Fish populations in a tidal estuary in Marlborough Sounds, New Zealand, from 1971 to 2004. 74pp. Self published on the United Nations website.
McCune, B and E.W. Beals. 1993. History of the development of Bray-Curtis ordination. In John T. Curtis Fifty Years of Wisconsin Plant Ecology, ed. J.S. Fralish, R.P. McIntosh and O.L. Loucks, 67-79. Wisconsin Academy of Science, Arts & Letters. Madison.
Mladenoff, D.J. and R.L.Burgess. 1993. The pedagogical legacy of John T. Curtis and Wisconsin plant ecology: 1947-1992. In John T. Curtis Fifty Years of Wisconsin Plant Ecology, ed. J.S. Fralish, R.P. McIntosh and O.L. Loucks, 145-195. Wisconsin Academy of Science, Arts & Letters. Madison.