Sporophyte Production and Sexuality of Mosses in Two Northern Michigan Habitats

The hypothesis that dioicous mosses produce sporophytes less frequently than monoicous mosses was tested by sampling populations in two contrasting habitats. In a dry aspen forest the mean percentages of populations with sporophytes were 75.9 for monoicous and 19.3 for dioicous species, while in a wet coniferous forest the means were 84.1 for monoicous and 12.3 for dioicous species. Dioicous species with antheridia borne in splash cups showed significantly higher sporophyte production than those without splash cups. However, dioicous species with male plants dwarfed and epiphytic on female plants did not show significantly greater sporophyte production. Differences in sporophyte production between habitats were minimal.