Haynes returned to New York from Paris in 1902 and studied botany with Marshall A. Howe at the New York Botanic Garden. Haynes was a strong supporter and contributor of the Sullivant Moss Society and The Bryologist botanical journal. She frequently gave aid in times of financial difficulties to the Society. Between 1908 and 1913 she issued the exsiccata series American Hepaticae. Prepared by Carolyn Coventry Haynes.