Stone, who taught at UC Berkeley for 39 years and continued to conduct research up until last year, died Jan. 11 at the Kaiser Foundation Hospital in Walnut Creek following a short illness.

Early in his career, Stone stood out as a persuasive leader in the field of forest ecology. His meticulous studies of how seedlings regenerate roots throughout the year led to changes in planting practices in the Sierra Nevada. Up until the 1950s, foresters planted seedlings in the fall, but Stone's research revealed that survival rates for the seedlings significantly increased if they were stored under refrigeration and planted in the spring.

There was little initial support for his views. Undaunted, Stone convinced the industry to change its practices with a provocative paper, "Planting Dead Trees - A California Tradition," presented at a meeting of the Northern California chapter of the Society of American Foresters.

"That paper and Ed's strong arguments led to a major change in nursery practices, switching from fall planting to spring planting," said Janet Cavallaro, a research scientist in forest ecology at UC Berkeley and one of Stone's last graduate students.

To better understand the factors affecting tree growth, Stone built five state-of-the-art controlled environment rooms in the basement of the Oxford Tract greenhouse, where they remain today. Many of his colleagues still consider the rooms impressive by today's standards.

"Ed installed xenon lamps to mimic daylight intensity and color, and water baths to control root temperatures," said Cavallaro, who continued working with Stone for more than 10 years after she received her PhD in forest ecology. "His growth rooms also closely controlled air temperature and humidity. He was able to conduct very solid research and became one of the foremost experts on the environmental conditions affecting the growth of redwoods, Douglas fir and other tree species."

Stone was born in Cairo, Ill., on Nov. 28, 1917, the fifth of seven children. Two years later, the entire family moved to Berkeley, where Stone attended the city's public schools. In 1940, he received his bachelor of science degree with highest honors in agriculture at UC Berkeley.

He met his wife, Gwendolyn Anderson, at UC Berkeley, and they married in 1941 shortly after she received her bachelor's degree in child psychology.

Stone had already begun his graduate studies at UC Berkeley when World War II intervened. He started as a civilian teaching calculus to pilots and navigators before enlisting in the U.S. Army Air Corps shortly after the bombing of Pearl Harbor. By 1946, when he was released from active duty, he had risen to the rank of captain and was provost marshall of the Clark Air Base in the Philippines.

In 1948, Stone returned to UC Berkeley and earned his PhD in plant physiology. He joined the faculty as an instructor in 1949 and continued teaching - with the exception of two years when he was recalled to service by the U.S. Air Force during the Korean War - until he retired as a professor in 1988.

"My father became interested in teaching from his experience in the military," said Brian Stone, whose wife, Sandra, is one of Edward Stone's former students. Brian and his brother, David, also received their bachelor's degrees at UC Berkeley and have gone on to become foresters with the USDA Forest Service.

Stone's two sons recalled their father investigating trees and evaluating soil conditions on the numerous camping trips they took with their parents. Edward Stone regularly took his family with him to Meadow Valley, Calif., where he taught at the summer camp program for UC Berkeley undergraduate forestry students. At the camp, he helped expand the curriculum to include studies in fields such as ecology, soils, entomology, fire behavior and genetics.

Stone was noted for his passion for teaching and the strong support he showed his students throughout their careers. He felt strongly that his teaching and research be relevant to foresters in the field. Barbara Allen-Diaz, executive associate dean of the College of Natural Resources, is one of Stone's former forest ecology students.

"Ed was a demanding teacher who challenged me to think for myself," she said. "He cared enormously about us as students, about forest ecology, and about science. He was truly an inspiration."

Even after he retired from teaching, Stone actively continued his research at UC Berkeley. Stone and Cavallaro carried out extensive research to model the productivity of white fir and ponderosa pine ecosystems in relation to the growing space of trees of varying heights. His final paper on root growth capacity of the white fir, co-authored by Cavallaro and UC Berkeley research associate Edward Norberg, is scheduled to be published later this year in the scientific journal New Forests.

Stone earned many professional accolades throughout his career and was a Fellow of the American Association for the Advancement of Science. In 1959, he received a Fulbright Research Scholarship for studies of Monterey pines in New Zealand, and a Guggenheim Fellowship for work in Australia and South Africa. In keeping with his love for trees and travel, Stone visited Tunisia to help in the country's forest development efforts in the early 1970s as part of a United Nations program.

In 1988, Stone received the Berkeley Citation, one of the campus's highest honors for extraordinary achievements in his field and outstanding service to the university.

Stone is survived by his sons, Brian of Benicia, Calif., and David of Blairsden, Calif.; and four grandchildren.