Marking Time highlights one of the more than 2,500 markers that have been installed throughout the state since 1914 as part of the Pennsylvania Historical Marker Program, operated by PHMC's State Historic Preservation Office.
Humphry Marshall marker dedication. Photo by Jim Lawson,

Humphry Marshall marker dedication.
Photo by Jim Lawson,

Humphry Marshall (1722-1801) has been called the Father of American Dendrology, the study of wooded plants. In 1785 he authored Arbustum Americanum, a catalog of American trees and shrubs following the Linnaean system of plant classification, the first publication of its kind.

A stonemason by trade, Marshall took an early interest in botany. His cousin John Bartram (1699-1777), who had created a botanical garden in Philadelphia, encouraged his younger relative in this pursuit. In 1773 Marshall established his own botanical garden of native and exotic plants on his property at Marshallton in what is today West Bradford Township, Chester County. There he cultivated new species and developed a lucrative business selling his plants. Not only did he supply clients in America but also in Europe. Plants from his nursery graced the gardens of both King George III of England and King Louis XVI of France. He sold to the scientific botanical gardens in Brussels, Holland and Italy and supplied the commercial forests of Germany as well. Although Bartram was a well-respected naturalist and sold seeds and plants from his garden around the world, Marshall surpassed him in commercial success.

Marshall’s nephew, Moses Marshall (1758-1813), lived and worked with him for many years. Moses contributed greatly to both research and business at the nursery. After Humphry passed away, Moses continued to cultivate and sell plants until his own death.

Humphry Marshall was also an early advocate for forest conservation and scientific farming methods, which he introduced as an honorary member of the Philadelphia Society for Promoting Agriculture. A friend of Benjamin Franklin, he was elected to the American Philosophical Society. Franklin introduced Marshall’s writings to the Royal Society in London, and his work was esteemed by scientific communities throughout the American colonies and Europe.

The Humphry Marshall House.

The Humphry Marshall House.
State Historic Preservation Office

While pursuing his botanical business, Marshall operated a mill and ran a successful farm. Fascinated by the natural world, he was an amateur astronomer. He incorporated both an observatory and a conservatory in the house he built on his property. Over the years subsequent owners made additions and renovations to the house, but today it remains largely intact. Although the gardens are currently not maintained as they would have been in Marshall’s day, they do contain some of the original plants that Marshall himself cultivated. The property, now under private ownership, was designated a National Historic Landmark by the National Park Service in 1987 and is within the boundaries of the Marshallton National Historic District. A Pennsylvania Historical Marker for Humphry Marshall, located at the house on West Strasburg Road, was dedicated in October 2014.


Karen Galle is on the staff of PHMC’s State Historic Preservation Office and has been the coordinator of the Pennsylvania Historical Marker Program since 2005.