Dr. Walter P. Cottam, eminent Utah ecologist and conservationist and professor emeritus of botany at the University of Utah, died Dec. 22, 1988, of Alzheimer's disease in Gresham, Ore. He was 94.

Dr. Cottam was an outspoken advocate of conservation long before the environmental movement began in the United States. He lectured and wrote widely about the necessity of conserving water, soil and plant resources.His revolutionary lecture, "Is Utah Sahara Bound?" delivered in 1947 while he was a professor in the U. botany department, aroused the ire of stockmen and sheepmen who had been over grazing and abusing the land. But it was largely through Dr. Cottam's efforts that land practices changed and conservation became a reality in Utah.

Dr. Cottam taught at Brigham Young University for 12 years, then went to the U. in 1931 and remained there for 31 years, serving as head of the botany department much of the time. He retired in 1962.

Many former U. students remember his "Spring Flowers of the Wasatch" as one of the best classes they ever had. With all his honors, Dr. Cottam felt that teaching may have been his greatest accomplishment. Many of his students have gone on to become authorities in their fields and continue to promote his ideas of preserving and conserving the land.

It was after his retirement that he started an oak hybridization project that brought him wide acclaim. He developed as many as 50 new oak hybrids, and was the first person in the nation to cross two species of oak from two different classes, a phenomenon that does not occur in nature.

A three-acre plot of land above Fort Douglas near the mouth of Red Butte Canyon now holds many of his best hybrid oak crosses. Hundreds of acorns from his hybridized trees have been planted and are flourishing throughout the United States. The onset of Alzheimer's disease a few years ago forced him to give up his experiments.

He was named "Man of the Year in Conservation" in 1957 by the Utah Foresters Club of Utah State University, and was cited as "Eminent Ecologist for 1960" by the Ecological Society of America.

He won the American Motors Conservation Award in 1963, the National Council of Garden Club's gold medal - its highest award given only to individuals for national or worldwide contributions to horticulture - and a distinguished service award from the Utah Academy of Sciences, Arts and Letters.

He helped establish the Salt Lake City Shade Tree Commission and served as a member for 25 years. He was given the Certificate of Merit from the National Shade Tree Conference in 1959. He was one of the founders of the Nature Conservancy and a member of many scientific organizations. His written works include many articles and a book, "Our Renewable Wildlands - A Challenge."

Dr. Cottam earned his bachelor's and master's degrees at BYU and his doctoral degree from the University of Chicago and was later visiting professor there. He wrote his dissertation on the Ecology of the Flora of Utah Lake. He served as an instructor in the Armed Forces school in England during World War II.

He was born March 3, 1894, in St. George, a son of Emmaline Jarvis and Thomas P. Cottam. He married Effie Frei July 1, 1915. She died in 1964.

He is survived by three sons and two daughters, Grant Cottam, Madison, Wis.; Richard Cottam and George Cottam, Pittsburgh, Pa.; Mrs. Charles (Fae) Olson, Gresham, Ore.; and Mrs. William (Bea) Fowler, Lakewood, Colo.

Memorial services are scheduled Dec. 29 at 1 p.m. at Larkin Mortuary, 260 E. South Temple. His body will be cremated. The family suggests donations to the Utah State Arboretum.