American corporate attorney in New York. Kenneth MacKenzie collected plants in many parts of the United States and became an authority on the sedges (genus Carex). He is responsible for publishing numerous papers on the subject and describing a vast number of species in this genus. MacKenzie also described species in the Asteraceae, Boraginaceae and Fabaceae families, among others. Some of his more important publications include Manual of the Flora of the Jackson County, Missouri (1902) and New Plants from Missouri (1902). From 1924 until the time of his death he served on the board of managers for the New York Botanical Garden. In 1932 MacKenzie presented his herbarium of 43,000 specimens to the New York Botanical Garden, along with 1,000 illustrations and 10,000 dollars to enable them to be published. He also maintained an impressive botanical library which was presented to the Horticultural Society of New York at his death.

MacKenzie was born in Brooklyn, New York, but raised in Muscatine, Iowa. Attending Kansas City Law School he was awarded a bachelor's degree in law in 1889 and later studied at Columbia University, graduating with the same degree in 1906. From this time onwards he was based in New York City.

Sources:
Anon, 1935, "News Notes: Mr Kenneth K. MacKenzie", Torreya, 34; 155-156
J. Ewan, 1950, Rocky Mountain Naturalists: 256-257
E.D. Merrill, 1934, "Kenneth Kent MacKenzie (1877-1934)", Proceedings of the Linnean Society , 147: 184-185
F.A. Stafleu and R.S. Cowan, 1976-1998, Taxonomic Literature, 2nd edition (TL-2): 3: 227.