User:Yayahme/Polygonum striatulum

Polygonum striatulum (synonyms Polygonum striatulum var. texense and Polygonum texense) is a flowering herbaceous perennial in the Knotweed family. Its common name is Texas Knotweed or Striped Knotweed and it is endemic to Texas.

Description
Polygonum striatulum is a light green herbaceous plant with brown rhizomes of diameters 0.7-3 cm and stems growing between 25 and 60 cm and branching sparingly in the top half. They have linear or lanceolate leaves that are pointed at both ends and are pinnate. These plants have small 2.5-3 mm flowers composed of overlapping, oblong tepals that are green and white or pink. Flowering occurs from December to March or from June to October. Members of the species that have leaves with less-conspicuous veins and flower from August to October are more often identified as P. texense and P. striatulum var''. texense''. The plants are deciduous and lose their leaves at the end of their growing season.

Taxonomy
Polygonum striatulum was described by Benjamin Lincoln Robinson in 1904. Its synonyms include ''Polygonum striatulum var. texense described by M. C. Johnston and Polygonum texense described by M.C. Johnston. P. striatulum is part of the family Polygonaceae and contains the subordinate taxa Polygonum striatulum var. striatulum. The names P. striatulum var. texense and P. texense more often refer to members of P. striatulum'' found in central and west Texas with less conspicuous leaf venation.

Distribution and Habitat
P. striatulum is endemic to Texas and is grown ornamentally outside of the region, but it has been documented in wild populations in Louisiana and Oklahoma. It grows at elevations between 100 and 700 meters and prefers granitic soil or sterile prairies. It requires seasonal moistness and it is considered a wetland plant. Plants labeled P. texense and ''P. striatulum var. texense'' are distributed primarily in central and western Texas.

Uses
Members of the Polygonum genus are associated with photo-sensitivity if consumed and most, but not all, are considered toxic. When consumed they affect both humans and livestock.