Thelypteris palustris - Schott
Thelypteridaceae (Marsh Fern) Family
The preferred habitat of Eastern Marsh Fern is in low woods, along creeks, in wet roadside ditches, and in low pastures. The plant often occurs in saturated soils or even shallow water in full sunlight. It requires constant moist soils and is one of the few ferns that thrive in direct sun; a vigorous grower wide spreading slender rhizomes.
The leaves (fronds) are erect to arching, elliptic to lanceolate in outline, broadest near the middle, and once pinnate with lobed pinna; deciduous. The petiole is yellow-green in color, about as long as the blade, and brittle. The pinna lobes are rounded to slightly pointed at the apex, and the basal veins from adjacent pinna lobes join before reaching the sines. The pinna are lobed nearly to their base. The veins are forked. The leaf is slightly pubescent on the veins, but the blade tissue is glabrous.
Eastern Marsh Fern reproduces by forming spores. The spores are produced in sporangia that are grouped together in clusters known as sori. The sori are located about mid-way between the main vein of the pinna lobes and the margin. The sori are covered with a round, pubescent flap of tissue known as the indusium.
Eastern Marsh Fern is a vigorous grower, wide-spreading slender rhizomes. Under the right conditions the plant can become weedy in the garden.