Herbs, annual, prostrate to ascending, occasionally erect, sometimes forming mats, glaucous or green, 0.5-10 dm. Stems prostrate, decumbent, or erect, usually light brown, simple or branched, sometimes slightly woody at base; main branches arising from proximal part of plant. Leaves ascending or spreading; blade linear, usually subterete, sometimes flat, 10-50 × 0.8-1.7 mm, apex blunt to acute. Glomes on main stem and lateral branches, not crowded into compound, distal spikes, 1-4-flowered; proximal bracts resembling leaves, distal bracts gradually reduced, 3-12 mm, slightly wider at the base. Flowers bisexual; perianth actinomorphic to slightly irregular with segments subequal, 2-3.3 mm diam.; perianth segments thin to abaxially rounded and occasionally distally hooded at maturity, without appendages, apex obtuse; stigmas 2-3(-5). Seeds monomorphic, lenticular, 1-2.2 mm diam.; seed coat reddish brown or black, reticulate. 2n = 36. Flowering late summer-fall. Coastal salt marshes, ballast; 0-10 m; Man., N.B., Nfld. and Labr. (Nfld.), N.S., P.E.I., Que.; Conn., Maine, Mass., N.H., N.J., N.Y., Pa., R.I., Va.; Europe; Asia (Arabia); Africa; Pacific Islands (Japan, New Zealand). Suaeda maritima is a polymorphic taxon with a worldwide distribution, including native and naturalized populations. Many varieties and subspecies have been described, mostly distinguished by seed size and growth habit (J. Boucaud 1962; I. J. Bassett and C. Crompton 1978). Small, procumbent, mat-forming plants from Newfoundland and Nova Scotia with seeds 1-1.5 mm in diameter have been called subsp. richii, whereas subsp. maritima has seeds 1.5-2 mm in diameter (I. J. Bassett and C. W. Crompton 1978). Seed dimorphism has been reported from populations in Europe (D. Metzing 1996) and may also exist in some North American populations.