This section is from the book "British Wild Flowers - In Their Natural Haunts Vol5-6", by A. R. Horwood. Also available from Amazon: A British Wild Flowers In Their Natural Haunts.
This species is found in sandy places near the coast and in muddy salt marshes. The plant has the grass habit. It has been considered a hybrid between P. monspeliensis and Agrostis alba by Douval-Jouve. The root is creeping. The stem is erect or prostrate, slender below. The panicle is close, lobed, purplish. The glumes are linear to lance-shaped, faintly notched, acute, as long as the awns. The empty glumes are smoother than in the next, more acute, the awns not so long, the keel rough. The flowering glume is one-third shorter, awned. The awns project. The plant is 4-18 in. high, flowering in July and August, and is a herbaceous perennial.
The habitat of this grass is damp places, especially near the sea, maritime sandy marshes, and cultivated ground (inland). The plant has the grass habit. The stems are tufted, erect or ascending, leafy, slender. The leaves are rough at the edge, short, flat. The sheaths are smooth. The ligule is oblong. The panicle is large, dense, spike-like, spindle-shaped to cylindrical, pale-green, and glistening. The branches are rough. The glumes are lance-shaped, with a long narrow point, swollen (hence Gastri-diitm), polished, shining below. The ultimate flower-stalks are swollen above. The empty glumes are erect, long-pointed, the keel faintly rough. The flowering glume is white, shining, with 4 teeth. The awn projects near the top, and is very slender, longer than the glumes. The plant is 12-18 in. high, flowering between June and October. The plant is a herbaceous perennial.
The habitat of this grass is sandy coasts on the east coast of England. The plant has the grass habit, like the commoner form. From the latter it is distinguished by the looser, less cylindrical, long, interrupted panicle, the more lance-shaped, long-pointed glumes, more acute, like the palea. The nerves in the flowering glumes are less distinct. The glumes are twice as long as the hairs. It has been supposed to be a hybrid between the common form and Calamagrostis Epigeios. The panicle is not so silvery-white. The plant is 2-4 ft. high, flowering between June and September, and is a herbaceous perennial.
The habitat of this plant is sandy shores. The plant has the grass habit. The stems are numerous, erect, or prostrate below, stout, downy, leafy at the base. The leaves are short, broad, flat, lance-shaped, downy. The sheaths are downy and inflated. The ligule is short. The spikes are white, blunt, egg-shaped (hence ovatus), soft. The empty glumes are very slender. The awn is twice as long as the nearly hairless flowering glume. The plant is 3-12 in. in height, flowering in June and July, and is a herbaceous annual.
The habitat of this grass is sea-coasts. At Salthouse, Norfolk, it forms a short turf on the landward side of the shingle banks. The plant has the grass habit, forming rigid, hard tufts. The stems are slender, bent below, hairless above, with short branches. The leaves are numerous, short, rigid, bristle-like, bluish-green, reddish below, the margins rolled inwards. The upper sheaths are long, rough. The ligule is lance-shaped. The panicle is narrow to oblong, silvery (hence canescens) or purplish, close, spreading in flower. The branches are short and thickened at the forks. The spikelets are narrow, pale-silver or purple, variegated. The empty glumes are narrow, long-pointed, with membranous tips. The flowering glumes are not so long, softly hairy below, the keel channelled. The awn is short or projecting, the lower part dark-yellow or purple below, straight and cylindrical, twisted, bearded in the middle where it is bent, the upper part club-shaped, white, with a purple tinge. The anthers are purple. The plant is 4-8 in. high, flowering in July, and is a herbaceous annual.