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.
The habitat of this plant is muddy salt-marshes. The plant is erect in habit. The root is spindle-shaped, with long fibres. The stem is hairless, leafy, corymbose above, with few branches, stout. The leaves are spoon-shaped, linear-lanceshaped, or inversely egg-shaped, succulent or fleshy, smooth, scattered, faintly 3-nerved, slightly toothed, the upper linear. The flowerheads are in a corymb, large, the disk florets yellow, complete, the ray florets purple, female, 20-30. The disk florets are tubular below, bell-shaped above. The flower-stalk is slender. The involucre is overlapping, with blunt phyllaries and membranous, the inner longer, closely pressed, few, oblong. The fruit is hairy. The pappus is dirty-white. The plant is 1-3 ft. high, flowering in August and September, and is a herbaceous perennial.
The habitat of this plant is maritime rocks, or salt-marshes, rocks, and muddy salt-marshes. The habit is erect. The plant is yellowish-green, hairless. The stem is stout, leafy, slightly branched near the top, each ending in a solitary head. The leaves are linear, stalkless, blunt or with 3 points, fleshy, succulent, narrow below, entire or with 2-4 shallow lobes. The flowerheads are few, in simple corymbs on long stalks, with orange disk florets, complete, and female ray florets, in 1 row, yellow. The involucral bracts are linear-lance-shaped, taper-pointed. The ligule is short. The fruit is round in section, silky. The pappus has an outer series of short bristles or scales, and is rigid, unequal, dirty-white. The plant is 6-18 in. high, flowering in July and August, and is a herbaceous perennial.
The habitat of this plant is sandy shores and sea shingle. The habit is prostrate below, then ascending. The rootstock is woody, creeping. The stems are numerous, stout, branched above. The plant is adapted to dry conditions densely cottony (hence Cottonweed), and white (hence candidissima). The leaves are stalkless, thick, blunt, entire or toothed, oblong, scalloped, and persist. The flowerheads are yellow, small, in dense, terminal, clustered corymbs. The involucre is cottony, the scales of the receptacle oblong, long-pointed, woolly at the tip. The fruit is smooth, hairless, 5-ribbed, curved. There is no pappus. The plant is 6-18 in. high, flowering in August and September, and is a herbaceous perennial.
The habitat of this plant is sea-coasts. The rootstock is woody. The leaf-segments are short, fleshy, shining, and succulent. The stem is ascending. There are no barren shoots. The heads are fewer. The receptacle is narrower. The spaces between the ribs of the fruits are narrower. The plant flowers between June and September, and is a herbaceous perennial.
Sea Wormwood (Artemisia maritima, L.) - - The habitat of this plant is salt-marshes and ditches. The habit is erect, prostrate, or ascending. The rootstock is woody, branched. The stem is branched, woolly. The leaves are white, woolly below, deeply divided nearly to the base, the segments linear, blunt, narrow, numerous, spreading. The flowerheads are drooping, few, crowded, oblong, in short panicle-like spikes, the florets reddish, all fertile, narrow. The receptacle is hairless. The phyllaries are oblong, the outer woolly, the inner membranous. The plant is 9-18 in. high, flowering in August and September, and is a herbaceous perennial.