Trenchard was born in Queen Anne's County, Maryland.

[4] During his early coaching career, Trenchard played professional football in 1896 for the Allegheny Athletic Association[5] and in 1897, 1898 and 1900 for the Latrobe Athletic Association.

[6] He also played for the 1898 Western Pennsylvania All-Star football team, formed by Latrobe manager Dave Berry.

[7] In 1895, and from 1913 to 1915, he coached at North Carolina, where he compiled a 26–9–2 record.

He is erroneously referred to as "T. C. Trenchard" in most North Carolina football media guides.