Thalictrum dioicum (Early Meadow Rue)

Britton, N.L., and A. Brown. 1913.  An illustrated flora of the northern United States, Canada and the British Possessions. 3 vols.  Charles Scribner’s Sons, New York. Vol. 2: 120. Provided by Kentucky Native Plant Society. Scanned by Omnitek Inc

Where Commonly Found:  Floodplains, wetlands, shores of rivers and lakes.

How to Identify

(For unfamiliar words: Wikipedia Glossary of Botanical Terms).
Go Botany Key for Thalictrum dioicum.
Illinois Wildflower’s description of Thalictrum dioicum.  Click on more images.

Flower Color:  Greenish white with purplish tinge
Flower Type:  Thalictrum dioicum is dioecious, meaning a plant has either all male or all female flowers.  Panicle, occurring at the top of the central stem.  Male flowers tend to droop more downward than the female flowers.  Male flowers are .25″ long and .5′ across, with 4-5 sepals that are broadly oblong, pale green, light-veined and white margined, and 10 or more stamens.  The female flower is about the same size as the male, same number of sepals, but more, up to 15, pistils that are grey with flat sided styles.  Neither male nor female flowers have petals.
Flower Time:  April to May
Leaf Arrangement:  Alternate along a central and some side stems which are pale green to pale purplish green, terete, glabrous and glaucous.
Leaf Type:  Compound, double or triple odd-pinnate, up to 1′ long and 1′ wide.  Each branch of a compound leaf has 3 – 5 leaflets with the branch having similar characters of the stems.  Leaflets are 1.75″ long and 1.75″ wide., reniform-orbicular to oval-orbicular with 3 – 9 terminal lobes, usually 5 or more.  The lobes are rounded or bluntly pointed.  Upper surface of the leaf is medium green, hairless and smooth and lower surface is pale green, hairless, with conspicuous raised veins.  The leaflets have slender petioles.
Height: 1′ – 2.5′
Seed Collection:  Female flowers are replaced with ellipsoid achenes that are pointed at both ends and ribbed.Fruit is dry but does not split when ripe.

Attracts:  Wind pollinated, so not noted as particularly attractive to pollinators.
Use:  Naturalized dappled light woodland garden, noted as deer resistant by Missouri Botanical Garden.
Light:  Full to part sun
Hardiness Zone:  4 – 7 USDA Zone Map
Soils:  Medium
Notes:  Lacey textured early bloomer, nice for dappled light naturalized garden.
Native to:  Native to most of the US east of the Rockies.  Biota of North America Program, North American Plant Atlas.

Requested by Bronx River Wildflower Corridor, Roseanne Andrade