Greater celandine is sometimes confused with wood poppy (Stylophorum diphyllum), a wildflower native to southeastern U.S. It doesn't help that both plants sometimes go under the common name "celandine poppy." The two plants have similar-looking leaves and flowers, though the flowers of wood poppy are much larger (1 to 2 inches wide). Another way to distinguish them is the seed capsules. Greater celandine capsules are slender and smooth (see the first photo), whereas wood poppy capsules are football-shaped and covered with soft bristles.
- Family: poppy (Papaveraceae)
- Habitat: damp roadsides and waste places
- Height: 1-2 feet
- Flower size: 1/2 to 3/4 inch
- Flower color: yellow
- Flowering time: May to August
- Origin: Europe

A flower and developing seed capsules. Photographed in mid-July in Philadelphia, Pennsylvania.

Celandine growing in an old stone wall in Philadelpia, Pennsylvania. Photographed in mid-July.

Photographed in Sussex County, New Jersey in mid-July.