Spotted Lady’s Thumb

Persicaria maculosa (Polygonum persicaria)

Non-Native

USDA, NRCS. 2018. The PLANTS Database (http://plants.usda.gov, 28 March 2018). National Plant Data Team, Greensboro, NC 27401-4901 USA.
Illustration: USDA-NRCS PLANTS Database / USDA NRCS. Wetland flora: Field office illustrated guide to plant species. USDA Natural Resources Conservation Service.

What is Spotted Lady’s Thumb?

Physical Characteristics

Leaves:

• Sword-shaped
• 1.19-6 inches long
• 0.2-0.7 inches wide
• Dotted red

Flowers:

• Few short, straight spikes
• Densely flowered
• 0.31-1 inches long
• 6 stamen

Fruit:

• Round
• Bulging on both sides
• Dark brown or black
• Shiny
• 0.08-0.11 inches long

Stem:

• 0.75-3 feet tall
• Green or marked with red
• Branching
• Swollen at nodes

Roots:

• Rooting at nodes

Where Does it Grow?

Non-Native

Spotted lady’s thumb is non-native to North America and should not be promoted. This plant can be found in marshes, ponds, lakes and streams.

Pros and Cons of Spotted Lady’s Thumb

This plant is not native to North America, but has naturalized in much of the United States. While it is not illegal to possess this plant in Texas, it should not be introduced into new water bodies and should be treated with herbicide when present.