This animation presents 1 year of data gathered between March 2000 and March 2001 at Pirates Beach located on Galveston Island Texas. The species represented in the change over time are presented in detail in this section.

Gulf Searocket Species Spotlight

Gulf searocket

Gulf searocket, Saltwater mustard, Sea rocket
Cakile geniculata

Description: Small to large stout herb, green plants with leaves 3-7 cm long that are broader towards the end with a few coarse serrations at the end. Fruit are circular in cross section and have joints along their length. Plants begin growth in January, flower very early and mature by early summer. As plants become mature, they lose their leaves and become woody as summer approaches.

Habitat: Windward and leeward slopes of sand dunes, base of dunes, and vegetation-stabilized sands and flats near beaches

Distribution: Texas to northwestern Florida

Status: A dune stabilizer and colonizer, particularly on front base of dunes

Seashore Dropseed Species Spotlight

Seashore Dropseed

Seashore Dropseed
Sporobolus virginicus

Description: Perennial, low growing, erect creeping grass up to 18 in tall, with stems rising from yellowish rhizomes or runners. Leaves linear, up to 5 in long and less than 1/5 in wide, rolled inwardly, internally divided into partitions by cell walls, hairy upper leaves shorter than lower leaves, leaf sheaths overlapping. One-flowered spikelet less than 1/5 in long borne in narrow, dense terminal inflorescence (panicle, 1-4 in long and less than 3/5 in wide) with rough branches. Small seeds densely clustered on elongate stem tip; often purple, red, yellow or gray. Flowering from Sept through Oct.

Habitat: Irregularly flooded salt marshes, salt barrens, sandy or muddy saline beaches and flats, back shore swales, backshore near dunes or dune ridges, windward and leeward slopes of slopes of dunes or dune ridges, bases of dunes, and salt marshes with sandy substrate.

Distribution: The coast from Virginia to Florida, west to Texas; also in Mexico, tropical America and the West Indies

Status: Excellent dune builder but overlooked as init to start formation of dunes.

Gregg's Amaranth Species Spotlight


Gregg's amaranth, Coastal pigweed
Amaranthus greggii

Description: Annual, tall, bright green, shrubby, pioneer herb exploiting suitable backshore sites of the dunes; somewhat rounded leaves with thick veins beneath. Male and female flowers are on separate plants and can be found on long spikes

Habitat: Backshore near coastal dunes, windward slopes of dunes

Distribution: Texas Coast; from Jefferson County, southward to Mexico; India and tropical America

Status: Excellent sand dune stabilizer

Sea Purslane Species Spotlight

Sea purslane

Sea purslane, Purslane sesuvium
Sesuvium portulacastrum

Description: Perennial, pioneering low growing, creeping, herb forming mats with smooth purple, orange, green or red stems rooting at nodes stems. Leaves fleshy, simple entire, linear to spoon-shaped, succulent and circular in cross section up to 2 in long and to 0.75 in wide with somewhat pointed tips and wedge-shaped bases, oppositely arranged. Small violet or pink star-shaped flowers (less than 1 in wide) with 5 petals with a prominent tip, borne singly on stalks from leaf axils. Fruit capsule about 0.5 in long bearing shiny black seeds. Flowers from May to Nov.

Habitat: Brackish marshes, mangrove swamps, sandy borders of salt marshes, irregularly flooded sand flats or barrens, backshore pioneer habitats, backshore near dunes or dune ridges, windward slopes of dunes, back half of many rock platforms, upper sandy beaches, spoil areas, coastal shores and flats

Distribution: North Carolina to Florida, West to Texas, also in tropical America

Status: Can make good dune initiator and stabilizer. Potherb, ornamental. Obligate and facultative wetland plant

Evening Primrose Species Spotlight

Evening Primrose

Evening primrose, Beach evening primrose
Oenothera biennis

Description: Perennial, herb with woody stems and leaves covered by fine hairs. Large, showy, unique, cup-shaped, yellow flowers that may turn red with age open in the evening or on cloudy days. Leaves are oval or pointed, 1-7 cm long and 5-15 mm wide. The margins of the leaves are smooth.

Habitat: Leeward slopes of dunes and vegetation-stabilized sands and flats of the coast.

Distribution: Gulf Coast

Status: No value for land management, but flowers beautify the dunes

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