The genus

The genus was named in 1818 by Thomas Nuttall (1786-1859), an English botanist and writer who worked in the USA from 1808 until 1841. He named it for Bernard McMahon (1775-1816) an Irish horticulturist who emigrated to the USA, eventually settling in Philadelphia. In 1796, McMahon established a nursery and seed shop in the city, run by his wife, which became a meeting point for the prominent horticulturists and botanists of his day. Some of the plants McMahon cultivated were grown from seeds sent to him by keen gardener and third President of the United States, Thomas Jefferson. One of these was the Berberis aquifolium, collected by Lewis and Clark on their famous exploration of western America 1804-06, which shortly after McMahon’s death would be renamed Mahonia aquifolium in his honour. He also provided Jefferson with many plants for his garden at Monticello in Virginia.