Racomitrium elongatum prefers open, dry, sandy soil.
The hydrated shoots form bright, yellow-green mats or rounded tufts. Dry shoots have a grayish appearance. These dry shoots are easily fragmented, the fragments probably propagate asexually.
The leaf apex is twisted, with a short white awn.
The leaf laminae are unistratose, while the costa is multistratose. The margin is recurved and unistratose.
Sporophytes are dark red-brown when mature.
The sporangium is long with an elongate operculum. The operculum is usually pleated.
Mature seta are twisted near the sporangium. The sporophytes in this photo however, are not fully mature.