Stylophorum diphyllum #1 (Wood Poppy)

Wood Poppy, also called Celandine Poppy, is a native woodland wildflower with showy, 2″ wide, bright yellow flowers held above fuzzy, lobed foliage.  The plants make tidy, bushy clumps of dense foliage with a long blooming period of four weeks or more. The flowers provide only pollen to insect visitors. Rounded, pickle-shaped, softly bristled seed pods form and go from green to yellow before bursting open and spilling the seeds to the ground below to be carried off by hungry ants. The ants eat the oily appendage attached to the seed coat (called elaiosomes.) The undamaged seeds are then discarded in their midden heaps, which are a perfectly rich and protected substrate for the seeds to germinate in. Wood Poppies will freely self-seed around the garden, leading to large colonies of butter-yellow flowers every spring. They can easily be dug and transplanted, shared with friends or left to mature and bloom for many years!

Wood Poppies are perfectly happy in moist, rich, deciduous shaded locations. After seed development in late spring to early summer, the foliage can begin to yellow and go dormant, especially in drought situations. If enough moisture is present in the soil through summer, it is possible that the plants can remain into the fall. Seedlings tend to not go dormant as quickly as mature plants.

There is a non-native and invasive look-alike called Greater Celandine (Chelidonium majus) that is naturalized in disturbed and sunnier areas. These two species can be most easily distinguished by their seed pods, among other identifying factors. The non-native has long, narrow and upright seed pods with no bristles or hairs, while our native Celandine Poppy has rounded, dangling and bristly seed pods.

Sources:
Growing and Propagating Wildflowers by William Cullina
Eastern/Central Medicinal Plants and Herbs by Steven Foster and James A. Duke
Missouri Botanical Garden
Lady Bird Johnson Wildflower Center
Illinois Wildflowers