Ehrenfried Pfeiffer (1899-1961) was born in Munich. He visited the USA several times in the 1930s, was awarded a doctorate for his groundbreaking Sensitive Crystallisation theory as a blood test for detecting cancer, and emigrated there in 1940. He pioneered biodynamic agriculture in the USA and helped found the Biodynamic Farming & Gardening Association. He died in Spring Valley, New York. Michael Maltas was born in Zimbabwe (then Rhodesia) in 1950. He studied science at Cape Town University, and then biodynamics at Emerson College in the UK. He moved to the USA and managed a biodynamic dairy farm in Missouri where he set up experiments to measure the effects of biodynamics on fruit trees. He later worked at the Fetzer vineyards in California. He still designs biodynamic gardens, and lives in Ukiah, California.