flowers of serpent grass

adders agent alpine altitude august bistort bistorta bloom blossom carnea caucasian caucasus chain chine cirque corrie english field floral flower flowers glacier grass grassland green hemostatic high highland hump knotgrass last meadow meadows medicinal mountain mountains peaks plant plants polygonum ranges ridge season seneca senega serpent serpentary side snakeroot snakeweed snowcapped snowy spine system valley views wort