Iris pseudacorus
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 courtesy of University of Florida/IFAS Center for Aquatic and Invasive Plants. Used with permission.
What is Yellow Flag?
Physical Characteristics
Leaves:
- Upright
- Arching at the top
- Flat
- Grow from the soil
- Sword-shaped
- Thin
- Pointed
- 3-4 feet tall
Flowers:
- Upright
- 3-4 feet tall
- Big
- Showy
- Yellow in color
- Many flowers on each stem
- 3 sepals pointing down
- 3 small petals
- 6 large petals
- Sepals light brownish-purple veined
Fruit:
- Seed pod
- 1.5-3 inches long
- 3 sided
- Cylinder shaped
- Green in color
- Many seeded
Seeds:
- Flat
- Brown in color
Stem:
- Thick rhizomes
- 0.39-1.5 inches across
Roots:
- 3.94-12 inches long
Where Does it Grow?
Non-Native
Yellow flag native to Europe. This plant can be found in marshes, wet savannas, pinelands, shallow water in ditches and in soggy meadows.
Is it Invasive?
Yellow flag is non-native to the United States, and it can be an aggressive invader that can cover large portions of land in a short period of time, and tends to disrupt the ecosystem by pushing the native species out of their habitat.
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 probably should not be introduced into new water bodies.