Texas Gardening: Texas Native Plant Pictures (Fern, Moss, Lichen & Mushroom), 0 by htop

htop wrote:
Downy Maiden Fern, Downy Shield Fern, Tapering Tri-vein Fern, Mountain Woodfern (Thelypteris dentata), Thelypteridaceae Family, native, perennial, evergreen in areas without hard freezes

USDA County distribution:
http://plants.usda.gov/java/county?state_name=Texas&statefip...

Regional distribution:
http://www.csdl.tamu.edu/FLORA/cgi/vpt_map_name?reg=1&name=<...)+E.+St.+John

This fern is commonly known as downy shield fern or downy maiden fern because it is covered with soft hair and has a more or less vertical stature. It can be found growing along roadsides and flood plains, under bridges and in rocky hammocks and moist woods. Although downy maiden fern prefers moist areas, it can grow in dryish, acidic sand. It has a short, stout stem and is 40 to 150 cm tall. The pinnate-pinnatifid blade is 20 to 100 cm long and approximately 25 cm wide. The pinnae (leaflets) are 7 to 17 cm long by about 3 cm wide. They are shallowly cut into blunt, square-shaped lobes. The upper surfaces and lower surfaces are covered in short hairs which give the plant a dull green color and a velvety texture. The lower frond stems lack hairs. Several pairs of the lower pinnae steadily decrease in length toward the base. The fronds that are fertile have longer petioles, the leaflets are closer together and are wider. The sori which are clusters of sporangia (spore-bearing sacs on the underside) are round or kidney shaped. There are 3 to 5 of them that are parallel and on either side of the pinnule (smaller leaflets into which each leaflet is divided) midvein. The base veins of each pair of adjacent pinna (singular for pinnae) lobes unite into one vein which runs to the edge of the pinna, making a triangle; hence, the name tri-vein fern. This is difficult to see with the naked eye.

Thelypteris dentata looks like several other members of its genus; however, the very reduced pair of basal pinnae (the lower leaflets) which causes the frond to have a tapered shape is one identifying feature. The shallowly cut, rounded pinnules (smaller leaflets into which each leaflet is divided) is another distinguishing characteristic.

For more information, see its entry in the PlantFiles:
http://davesgarden.com/guides/pf/go/142273/

Habit ... Photo courtesy of Forest and Kim Starr.