In memoriam: Nat B. Dellavalle

Nat B. Dellavalle, respected agronomist, founder of Dellavalle Laboratory, Inc., and a deeply influential figure in California agriculture, passed away on November 29, 2025, surrounded by family. He was a CPSS since 1980, a CCA since 1996, and a 60-year member of the American Society of Agronomy (ASA) and Soil Science Society of America (SSSA). Dellavalle leaves behind a legacy of scientific excellence, integrity, and service to growers and communities he supported for more than five decades.

Born with an analytical mind and a natural curiosity, Dellavalle pursued his passion at Cal Poly San Luis Obispo where he earned a degree in Soil Science. After establishing laboratories for two agricultural chemical companies, he recognized the need for a rigorous, grower-focused laboratory and consulting service. In 1978, he founded Dellavalle Laboratory, Inc., which grew into one of California's premier soil, plant tissue, and water analysis laboratories. Through his leadership and commitment to scientific accuracy and economic balance, the laboratory helped generations of farmers better understand and care for their land, improving agricultural practices across the West and beyond.

Dellavalle’s professional influence extended far beyond his own laboratory. He served on boards and committees for numerous professional organizations, including the Soil and Plant Analysis Council (SPAC), ASA, SSSA, and regional nutrient-management working groups. He contributed to the development of quality-assurance standards for soil and plant analysis laboratories, participated in regional and national conferences, and mentored countless agronomists and laboratory professionals.

His peers recognized his impact repeatedly. Dellavalle received the J. Benton Jones Jr. Award from SPAC—one of the field's highest honors—for significant scientific and educational contributions to soil testing and plant analysis. In 2017, he was awarded the Western Nutrient Management Conference Leadership Award, acknowledging his decades of guidance, innovation, and service to Western agriculture.

Beyond his professional achievements, Dellavalle was known for his generosity, patience, and respect for others. He loved helping people understand the soil beneath their feet and believed deeply in agriculture's responsibility to future generations. Colleagues remember him as a steady, principled leader; clients remember him as a trusted partner who always took the time to listen.

Dellavalle approached life with thoughtful balance and a deep sense of purpose. He found meaning not only in science and business, but also in family, community, and stewardship. His influence will continue through the laboratory he built, the standards he helped shape, and the many people he taught and inspired.

He will be profoundly missed and forever remembered with love, gratitude, and deep respect.

Dellavalle is survived by his beloved wife, Ann; his children, Mary, Peter, Angela, and Joan; six grandchildren; and one great-grandchild with a second expected soon. He was immensely proud of his family, and nothing brought him greater joy than their accomplishments and time spent together.