Buxbaumia viridis, also known as the green shield-moss, is a rare bryophyte found sporadically throughout the northern hemisphere.

B. viridis is dioicus, with its antheridia and archegonia forming on small, singular leaves borne on the ends of the protonema.

[3] After the capsule matures in late summer to early fall, it develops its asymmetric shape and turns brown.

[1] Dry conditions can lead to protonema death, a reduction in spore count, and decreased germination.

[1][8] Buxbaumia viridis is widely distributed across the northern hemisphere, although populations are scattered and individual plants are scarce.

[7] It is known to co-occur with some other species of mosses and liverworts such as Herzogiella seligeri, Rhizomnium punctatum, Dicranum scoparium, Tetraphis pellucida, and Chiloscyphus profundus.

[6] Small slugs from the Arion genus have also been observed scraping the outer part of the capsule to eat the spores inside.

[6] Forestry practice such as clearcutting is one of the largest threats to this moss as it reduces new potential areas for establishment and removes cover.

[1] Some forest management practices can be helpful; breaking up substrate reduces the competition B. viridis experiences from other bryophytes.