The mode of seed reproduction in four species Calamagrostis of peninsula Kamchatka (Russia) flora has been examined (C. langsdorffii (Link) Trin., C. lapponica Wahl., C. neglecta (Ehrh.) Gaertn., C. sesquiflora Trin.). In C. lapponica and C. neglecta studied plants are characterized by highly degree of pollen sterility (61,2 and 24,8% respectively) and significant variation of pollen grains size (CV = 17,4 and 18,7%), which is typical for apomictic forms.
