Pteris vittata
Pteris vittata L.
(Latin: vitta, ribbon, band, or stripe, = longitudinally striped—in reference to the linear false indusium)
Local names: ladder brake, Chinese brake, Chinese ladder brake
Leaves not remaining green through winter, 0.3–10 dm long; leaf blades oblanceolate or narrowly so, 15–50(–80) cm long, to 16(–25) cm wide, strictly 1-pinnate, glabrous; pinnae 12–20(–30) pairs per leaf, not decurrent on rachis, linear lanceolate, to 18 cm long, serrulate, apically acuminate, basally asymmetrically cordate to truncate; distal pinnae conspicuously longer than proximal pinnae with the terminal pinna typically longest; 2n = 116 (Nauman 1993b). The only known TX collection is from a stream-side boulder in San Saba Co. (J.W. Stanford 5308, 1987, BRIT, HPC, SPLT) on the Edwards Plateau, the site subsequently destroyed by flooding; naturalized (apparently escaped from cultivation); se U.S. from SC s to FL w to TX, also CA and D.C. and invasive in Hawaii; also naturalized in ne Mexico (Nuevo Leon and Tamaulipas) and in various places in the New World subtropics and tropics. Sporulating in TX ?–Nov–?. Native of Asia. [Pycnodoria vittata (L.) Small] This species was first reported for the TX flora by Stanford and Diggs (1998). Small (1938) indicated that during the 1930s it appeared in abundance at several Florida localities (e.g., Everglades). It is now widely naturalized in the se U.S. on exposed limestone (e.g., pinelands) and on a variety of man-made calcareous substrates (e.g., sidewalks, buildings, old masonry) (Nauman 1993b). This species has been found to accumulate arsenic. It is a “hyperaccumulator” that is “extremely efficient in extracting arsenic from soils and translocating it into its above-ground biomass” (Ma et al. 2001). It is thus of potential use in remediating arsenic-contaminated soils (Bondada & Ma 2003). Since the species can tolerate high arsenic levels, this is presumably an adaptation for survival on soils naturally high in arsenic or possibly a defense against herbivores. Although not an invasive in TX, it is a prolific spore producer with a known ability to become invasive in other areas (e.g., in Hawaii). Therefore there are concerns about its potential widespread application in bioremediation (Robinson et al. 2010).