[1] Yonge was associated with the Southern State Lumber Company and its predecessors and served as president and manager of the corporation.
[2] An active citizen of Pensacola for nearly half a century, Yonge served as alderman from 1905 to 1909, and was president of the Chamber of Commerce in 1908.
[3][4] His son, Henry Yonge, Jr., had begun a career in law but because of his Loyalist leanings was forced to leave Georgia when the American Revolution broke out in 1776.
[5] Because of his Loyalist sympathies, in 1778 Henry Yonge, Sr., with his sons Philip and William John, was banished from Georgia as well by the rebel usurpers of the colony's government.
The elder Yonge became a lawyer and was only twenty years old when he served as assistant secretary of the first Florida constitutional convention held in 1838 at St. Joseph.
He was scholarly enough to be elected a member of the national honor society, Phi Beta Kappa.
By 1875 Yonge was engaged in the real estate and insurance business rather than the practice of law, and in 1876, he got into lumber manufacture and export, in which he was active for over fifty years.
In 1876, P. K. Yonge became secretary of the Muscogee Lumber Company, a position he held until 1889 when the business was taken over by the Southern States Land & Timber Company, of which he was made corporate assistant manager and manager of its New York office.
P. K. Yonge was a charter member of the reorganized Florida Historical Society in 1902 and served as its president from 1932 until his death in 1934.
He was an active collector of Florida historical materials and assembled a vast collection of books and documents that his son, Julien C. Yonge, inherited and further expanded.