University of California, Riverside

UCR Newsroom

Citrus Pioneer Homer Chapman, 106

Homer Chapman, One of UC Riverside's Founding Faculty Members, Dies at age 106

Professor Chapman was an influential citrus researcher and world traveler

(April 6, 2005)

Homer D. Chapman, citrus pioneerEnlarge

Homer D. Chapman, citrus pioneer

RIVERSIDE, Calif. ( -- Professor Emeritus Homer D. Chapman, a former director of the Citrus Experiment Station and a founding faculty member at the University of California, Riverside, died at the age of 106 on Monday, April 4. He lived in Riverside between 1927 and 1993, when he and his wife moved to a retirement home in Irvine.

Professor Chapman was one of the early pioneers in the development of leaf and tissue analysis for diagnosing the nutrient status of citrus trees. He contributed substantially to the work in citrus nutrition and soils research that made citrus such an economic powerhouse for California, and around the world. His leaf analysis standards are used world-wide today.

During his lifetime, which touched three different centuries, he saw the widespread introduction of cars and paved highways, of thermometers that can be shaken down and read, of air travel, of radio and TV.

Born in 1898 in Wisconsin, he studied agriculture first at the University of Wisconsin, Madison, earning a doctoral degree in 1927. He came to Riverside immediately after that as a researcher with the Citrus Experiment Station, which later would expand into the Riverside campus of the University of California.

“The only experience I’d had before with citrus was oranges in the Christmas stocking,” he quipped in one interview.

He married his wife, Daisy, at the Mission Inn. Throughout their over 70 years of married life, they traveled the world as Professor Chapman consulted for research organizations, governments and private corporations. They spent a year in Chile, six months in India, several month-long stays in Egypt and shorter visits to places including Russia, Australia and Norway.

“I was amazed when I visited South Africa in 1957, and one of the citrus growers hauled out his copies of the Citrograph [a magazine published by the International Society of Citroculture] to show me articles that I had written,” said Professor Chapman in an early interview. “It was the research on citrus that gained us the reputation around the world.”

Professor Chapman chaired the Department of Soils and Plant Nutrition from 1938 to 1961 and directed the Citrus Experiment Station from 1951 to 1952. He developed methods to determine fertilizer needs of citrus plants; chaired the committee that organized the first International Citrus Symposium; and served as the first honorary president of the International Society of Citriculture. He was the author of the " Mineral Nutrition of Citrus" chapter in both editions Volume II of the Citrus Industry published in 1948 and 1968. The Citrus Industry series (volume I-V) are considered the "citrus bible" for the industry and citrus researchers.

He retired from teaching in 1966 but remained active with his research and consulting.

He played jazz piano as a hobby and was a member of Riverside Kiwanis for 65 years. He remained in good health and didn’t give up driving until he was 99. He remained a supporter of UC Riverside throughout his life. He and his wife donated money in two funds, one to support research in plant sciences and citrus and another to support performing Arts.

Daisy Chapman died in 1999 at the age of 96. They did not have children, but Professor Chapman is survived by many nieces and nephews.

Services have not yet been announced.

The University of California, Riverside ( is a doctoral research university, a living laboratory for groundbreaking exploration of issues critical to Inland Southern California, the state and communities around the world. Reflecting California's diverse culture, UCR's enrollment has exceeded 21,000 students. The campus opened a medical school in 2013 and has reached the heart of the Coachella Valley by way of the UCR Palm Desert Center. The campus has an annual statewide economic impact of more than $1 billion.

A broadcast studio with fiber cable to the AT&T Hollywood hub is available for live or taped interviews. UCR also has ISDN for radio interviews. To learn more, call (951) UCR-NEWS.

More Information 

General Campus Information

University of California, Riverside
900 University Ave.
Riverside, CA 92521
Tel: (951) 827-1012

Department Information

Media Relations
900 University Avenue
1156 Hinderaker Hall
Riverside, CA 92521

Tel: (951) 827-6397 (951) UCR-NEWS
Fax: (951) 827-5008

Related Links