Oriental lady's thumb
Persicaria longiseta (Bruijn) Kitagawa
USDA PLANTS Symbol: PELO10
Asiatic smartweed, bristled knotweed, bunchy knotweed
- Persicaria longiseta is an annual forb that can reach 6-30 in. (15.2-76.2 cm) in height and can be either erect or sprawling.
- Leaves are elongate, narrow and pointed at the base and tip. Stems have swollen nodes with papery sheaths (ocrea). Ocrea have long, hair-like bristles on the margin.
- Flowering occurs from June to October, when pink flowers develop at the apex of the stems. Flowers are 0.13 in. (0.3 cm) long and occur in groups.
- Seeds are smooth, dark colored, dry, and 3 angled.
- Ecological Threat
- Persicaria longiseta is native to Asia and occurs in disturbed habitats such as along roadsides and in pastures. Plants also inhabit wet areas.
Identification, Biology, Control and Management Resources
Invasive Plant Atlas of New England
- University of Connecticut
Weed of the Week
- USDA Forest Service