was a distinguished pomologist and elder brother of
Andrew Jackson Downing. He worked part time as a boy
in his father's nursery. At 24 he became a nurseryman
himself with his brother Andrew a partner from
1834-1839. About 1850 he sold his business and devoted
himself to the study of cultivars of fruits upon which
subject he became an outstanding authority.
The great bulk of the work Fruits and Fruit
Trees of America was composed by him although
Andrew, his brother, conceived the idea. His test
orchard contained trees and "grafts" of 1800 apple and
1000 pear cultivars and others in proportion. He is
noted for his "conscientious accuracy."