Table 1. Phenology of sexual expression and sporophyte production in S. macrophyllum at Hell Hole Swamp.

Month	Male	Female	Nonexpressing	Sporophytes
December 2009	46	7	43	0
January 2010	40	16	40	66
February 2010	44	16	36	76
March 2010	40	31	25	182
April 2010	28	18	50	82
May 2010	0	24	72	151
June 2010	0	14	82	45
Total	198	126	348	602

A total of 96 plants were sampled at the same 8 locations (12 per location) within the population throughout one breeding season. Male plants were identified by the presence of antheridia (sperm-producing structures) during microscopic dissection. Female plants were identified through the presence of archegonia (egg-producing structures) or sporophytes. Plants with no sexual structures of either type were recorded as nonexpressing.