Esau, Katherine (1898–1997)

Russian-born American botanist, internationally recognized for her work in the field of plant anatomy and plant viral diseases. Born in Ekaterinoslav, Russia (now Dnepropetrovsk, Ukraine), on April 3, 1898; died in Santa Barbara, California, on June 4, 1997; daughter of John Esau and Margarethe (Toews) Esau; never married.

Katherine Esau was born in 1898 in the city of Ekaterinoslav, located in tsarist Russia's agriculturally productive province of Ukraine. Her parents John and Margarethe Esau were Mennonites, a religious minority from Germany who had sought refuge and land in imperial Russia in the 18th century. Empress Catherine II the Great granted the Mennonites tracts of land on which they could farm and flourish. As religious pacifists, they declined en masse to participate in wars, and the Russian empress took these convictions into account when she granted the group an exemption from military service for a full century. The Mennonites prospered in their agricultural colonies, maintaining a separate cultural, religious and linguistic identity, which by the late 19th century began to expose them collectively to Russian and Ukrainian accusations that they constituted alien islands of arrogant and inassimilable Germans in a Slavic sea.

Katherine's father John had an unusual background that helped shield against such charges from his Ukrainian and Russian neighbors. As one of the very few Mennonites who had attended Russian schools, he spoke perfect Russian and Ukrainian, had earned a degree as a mechanical engineer in Riga, and by the time Katherine was born in 1898 as his last child (son Nicolai and daughter Marie had died in infancy, and Paul, born in 1894, survived) the Esau family had become prosperous. A successful businessman, John Esau served first as a city councillor and then as mayor of Ekaterinoslav.

World War I proved difficult for the Russian empire as the backwardness of the state and the inefficiency and corruption of the tsarist system brought about increasing chaos. War-weary Russians overthrew the Romanov dynasty in early 1917 and by the end of that year Vladimir Lenin's Bolshevik Party had seized power so as to end the war and embark on creating a Marxist Utopia. Imperial Germany took advantage of the disintegration to conquer grain-rich Ukrainian lands, and with Ekaterinoslav now under German military rule John Esau once again sat in the mayor's seat. This time, however, events were highly unstable and, with the defeat of Germany in November 1918, the situation in Ekaterinoslav became anarchic.

Regarded by the local Bolshevik revolutionaries as a quintessential German alien, as well as the embodiment of a now-despised world of bourgeois capitalism, John Esau found himself declared a counterrevolutionary and an "enemy of the people." No longer able to guarantee his own or his family's safety, John Esau decided on the spot to quickly liquidate his assets as best he could. Packing essential possessions including food in suitcases for a long rail journey, the Esau family departed for Germany with once-proud but now demoralized German troops on December 20, 1918. The evening of their departure, an armed horde seized virtually all of the family's baggage including their food and clothing. The trip to their destination, Berlin, normally took two days, but in the utter chaos of revolutionary Ukraine it took two exhausting and dangerous weeks. Only the payment of large sums of money as bribes made it possible for the train to receive permission to pass safely through various areas that were controlled by motley revolutionary committees and local bandits.

Katherine Esau and her family arrived in Berlin on January 5, 1919, tired but safe. Berlin was itself suffering from bloody disorders at this time which climaxed in mid-January with the violent suppression of the Spartacist uprising that had intended to create a Leninist Soviet republic in Germany. Determined to find stability, the Esau family quickly settled down in Berlin. Their ability to speak German like natives facilitated their rapid acculturation to a new country despite the fact that the country sometimes teetered on the brink of anarchy. John Esau became active in Mennonite relief work while Paul continued his studies.

Soon after her arrival in Berlin, Katherine Esau had to decide what kind of academic program in which to enroll. In Ekaterinoslav, she had been an excellent student at the local gymnasium, showing a strong interest in the sciences. Graduating in 1916, she continued her studies in the fall of that year by enrolling at

Moscow's Golitsin Women's College of Agriculture. She excelled in her first year, taking courses in natural sciences, physics, chemistry and geology. At this stage in her life, she chose agriculture over botany, because she was convinced that botany was a sterile discipline that did little more than name and classify plants. She saw agriculture as an area full of new ideas that also could lead to practical results, including increased food production in a time of shortages and near-famine conditions. Katherine's formal education in Russia had ended with the Bolshevik Revolution, but during her final year in that ravaged nation she had continued her studies by learning English, taking piano lessons, attending a gardening school, and accumulating a collection of plant specimens that she planned to present as a completed project when more settled conditions made it possible to resume her interrupted formal studies.

Determined to achieve her educational goals despite her family's painful displacement, Katherine Esau registered in Berlin's highly regarded College of Agriculture. Unlike many refugees in that period, she was able to present her education credentials to the school's registrar, including not only the necessary documentation of her completed course work but even the gold medal that the Ekaterinoslav gymnasium had awarded her for academic excellence. She excelled in her studies and, during her second year, spent two semesters taking specialized agricultural courses in the Swabian town of Hohenheim near Stuttgart. Returning to Berlin to complete her course work, she graduated with the title of agricultural instructor (Landwirtschaftslehrerin). Additional courses with the noted geneticist Erwin Baur led to her certification as an expert in plant breeding. The politically naive Baur suggested to Esau that she should consider returning to Russia because, despite her youth, she now possessed skills that would enable her to make major contributions to that devastated nation's agricultural sector. Esau knew that as a hated bourgeois and member of a German Christian pacifist sect, she stood little chance of doing any effective work in Lenin's Soviet state. By this time, in fact, she and her family had already decided to immigrate to the United States.

Katherine Esau, with her parents and her brother Paul, arrived in the United States, settling immediately in Reedley, California, in which a large number of Mennonites lived as farmers. Katherine took a series of jobs including one in the town of Oxnard with a struggling seed company. The work was often hard but always challenging as she oversaw the planting of seed and learned Spanish in order to better communicate with Mexican laborers. Through no fault of her own, the company failed, and she soon found another job, this time with a sugar company in Spreckels, a California settlement near Salinas.

Esau's solid European education in plant genetics would serve her well on this assignment, which included developing a sugar beet that was resistant to curly top disease, a condition known to be caused by a virus transmitted by an insect, the beet leafhopper. A disease-resistant strain of sugar beet had already been developed, but it was of little economic value since it had a poorly shaped root and low sugar content. At Spreckels, Esau's job was to improve this beet's strain by hybridization. Ignoring primitive conditions and long hours, she spent the next few years developing the sought-after strain of sugar beet.

The quality of her work with sugar-beet hybrids eventually came to the attention of the chair of the botany division of the University of California at Davis (UC-Davis), and in the spring of 1928 Esau began full-time graduate work at the university's College of Agriculture at Davis. Although the bulk of her graduate work took place at Davis, she was officially enrolled at University of California at Berkeley, where she took a number of advanced courses in botany. An excellent student who was elected to Phi Beta Kappa, Katherine Esau was awarded her Ph.D. degree in botany in December 1931, officially receiving it at the 1932 Berkeley commencement.

The question of how Esau would support herself in an economically depressed country was quickly resolved when she was offered a dual position at the Davis branch of the University of California. Half of her time would be spent teaching, the rest carrying out research projects at the College of Agriculture's experiment station. At first, Esau was concerned that she would not meet the challenges of teaching, but once she began her instructional tasks, which included teaching plant anatomy, systematic botany, morphology of plant crops and microtechnique, she discovered that she enjoyed teaching. Her classes, which were popular with students, were conducted in a relaxed manner and enlivened by her keen sense of humor.

From the start of her academic career at Davis, Esau worked on an ambitious research agenda. She was particularly interested in the phloem tissue of plants, which conducted food through the organism. Her research findings over the next decades made important contributions to the understanding of how viruses are able to bring about the destruction of plant structures by spreading through a plant's phloem system. Her carefully executed and systematic investigations of infected and noninfected sugar beets clarified previously little-understood mechanisms of viral infection and degeneration in plants. Working with tobacco plants, she discovered that, in the case of the curly top virus, it was clear that the virus depended on the phloem for both initiating the infection and spreading it throughout the plant. With this work, she made a major contribution to an understanding of plant pathology, establishing the concept of a "phloem-limited virus."

Katherine Esau's work was her life. She continued to live with her parents in a house near the Davis campus, and it was here that she spent many hours in a darkroom working on microphotographs. There was a darkroom in the university botany division, but it lacked air conditioning and was miserably hot many months of the year. At home in the evenings, Esau could work at her own pace, meticulously developing photographs of plant structures. These would eventually appear in her classic textbook Plant Anatomy. First published in 1953, this text quickly became a standard work in its field, popularly known among students as "Aunt Kitty's Bible."

During World War II, Esau became involved in a project to find more productive rubberyielding strains of the guayule plant. Researchers had not been able to explain why certain guayule strains had failed to yield hybrids when crossed with other strains, producing instead an unwanted type of progeny. Painstaking work on her part explained the mystery, namely that the problem was due to fact that the plant had been able to reproduce without sexual union taking place. The next years were extremely busy ones for Esau, who carried out consequential investigations of diseases of grapevines, beets and celery. Collaborating over many decades with another distinguished botantist, V.I. Cheadle, she published many important papers relating to the evolutionary specialization of phloem tissue as it relates to plant functions.

In 1960, when Esau was in her early 60s, an age when other scientists often started planning for retirement, she began a new and even more productive phase of her scientific career when she began working with the electron microscope at UC-Davis. By this stage of her work, she had become world famous, with honors that included membership in the National Academy of Science.

In 1963, Esau moved to the University of California at Santa Barbara, where she continued her investigations of plant viral diseases. Collaborating with Lynn Hoefert, she made discoveries regarding the virus causing western yellows disease in beets. These insights were of great value for botanists worldwide who were trying to find a deeper understanding of the mechanisms of plant diseases, particularly in crops that played a significant role in the human food supply.

Throughout the 1960s and 1970s, Esau's productivity continued, although she had officially "retired" from her teaching duties in Santa Barbara in 1965. She continued to be involved in important experimental work while at the same time publishing a significant number of scientific papers. Her many reviews of the current botanical literature, which she had begun to publish early in her career, were a model of clarity and completeness, and they provided a vast sum of information for structural botanists. Her linguistic gifts (besides English, German and Russian, she could read books and journals written in French, Spanish and Portuguese) allowed her to transverse virtually the entire globe of botanical research.

Enjoying robust good health, Esau carried out research work into her late 80s. Unintimidated by the new, she mastered a personal computer in the mid-1980s when working on the revision of her standard textbook Plant Anatomy. She was the recipient of many honors in the final decades of her long and productive life. A building on the UC-Santa Barbara was named in her honor. The Botanical Society of America, which elected her to its presidency, created the Katherine Esau Award for the single most outstanding paper in developmental and structural botany. In October 1989, President George Bush awarded Esau the National Medal of Science: she was cited for the excellence of her work, "which has spanned more than six decades; for her superlative performance as an educator, in the classroom and through her books; for the encouragement and inspiration she has given to a legion of young, aspiring plant biologists; and for providing a special role model for women in science."

Katherine Esau died at her home in Santa Barbara, California, on June 4, 1997. She was praised by Dr. Peter S. Raven, director of the Missouri Botanical Garden, as one of the most influential botanists of the 20th century, an investigator who had "absolutely dominated the field of plant anatomy and morphology for several decades," and whose lasting achievement was to have "set the stage for all kinds of modern advances in plant physiology and molecular biology."

sources:

Abir-Am, P. G., and Dorinda Outram, eds., Uneasy Careers and Intimate Lives: Women in Science 1789–1979. New Brunswick, NJ: Rutgers University Press, 1987.

Esau, Katherine. Anatomy of Plant Seeds. 2nd ed. New York: John Wiley, 1977.

——. Plant Anatomy. NY: John Wiley, 1953, 2nd ed., 1965.

——. Plants, Viruses, and Insects. Cambridge, MA: Harvard University Press, 1961.

——. Vascular Differentiation in Plants. NY: Holt, Rinehart and Winston, 1965.

Evert, Ray F. "Katherine Esau," in Plant Science Bulletin. Vol. 31, no. 5. October 1985, pp. 33–37.

——, and Susan E. Eichhorn. "Katherine Esau (1898—)," in Louise S. Grinstein et al., eds., Women in the Biological Sciences: A Biobibliographic Sourcebook. West-port, CT: Greenwood Press, 1997, pp. 150–162.

Freeman, Karen. "Katherine Esau Is Dead At 99: A World Authority on Botany," in The New York Times. June 18, 1997, p. D23.

International Journal of Plant Sciences. Vol. 153, no. 3. Part 2, 1992, Katherine Esau Symposium Special Issue: Plant Structure—Concepts, Connection, and Challenges, University of California, Davis, March 28–31, 1992.

McDavid, Lee. "Katherine Esau (1898—)," in Benjamin F. Shearer and Barbara S. Shearer, eds. Notable Women in the Life Sciences: A Biographical Dictionary. Westport, CT: Greenwood Press, 1996, pp. 113–117.

O'Hern, Elizabeth Moot. "Profiles of Pioneer Women Scientists: Katherine Esau," in Botanical Review. Vol. 62, no. 3. July 1996, pp. 209–271.

Russell, David E. "Life in Czarist Russia: A Conversation with Katherine Esau," in Soundings. Vol. 23, no. 29, 1992, pp. 5–32.

John Haag , Assistant Professor of History, University of Georgia, Athens, Georgia