Thalictrum clavatum DC.

Sepal Characteristics

Thalictrum clavatum DC. flowers have no petals, and typically bear 4 to 5 white obovate-spatulate caducous sepals that measure 2.5 to 4.0 mm and detach once the plant flowers.

Flower Sexual System

Flowers are cosexual, containing both male and female reproductive organs.

Male Reproductive Structures

The male reproductive structures include numerous petaloid, flattened white filaments 2.5–4.0 mm long, and anthers 0.3–0.5 mm long.

Female Reproductive Structures

The female reproductive structures include a superior ovary and several white stigmas, with basal marginal placentation.

Individual Flower Morphology

Individual flowers are radially symmetrical (actinomorphic), arranged in a pom-pom shape, and measure roughly 1/3 of an inch wide.

Inflorescence Type

The overall inflorescence is a panicle or nearly corymb.

Pedicel Characteristics

The pedicel is slender and bears few to no leaves.

Proximal Cauline Leaves

Proximal cauline leaves, located toward the base of the plant, are petiolate, with 2 or 3 degrees of compounding.

Distal Cauline Leaves

Distal cauline leaves are sessile, with 1 or 2 degrees of compounding.

Cauline Leaf Arrangement

Both proximal and distal cauline leaves are bi-ternately compound, and arranged in an alternate configuration along the stem.

Leaflet Morphology

Leaflets are obovate with apically lobed tips, and measure roughly 10–30 mm wide.

Leaf Traits

Leaflets have no fragrance, their undersurface is glaucous (waxy), leaves are deciduous, broadleaf with ternate venation and crenate margins.

Root Characteristics

The roots of Thalictrum clavatum are few in number, black in color, and slightly tuberous.

Fruit Type

The fruit of this species is an achene: a dry, one-seeded fruit that does not open when ripe.

Achene Arrangement

Plants usually produce 3 to 8 achenes arranged in a spreading pattern.

Achene Stipe

Each achene has an elongated stipe (stalk) that measures 1.0–3.0 mm.

Achene Shape

Achenes are flat and sickle-shaped, with veining along their sides.

Stem Characteristics

The stem of Thalictrum clavatum is slender, smooth, green, erect, glabrous (hairless), and grows 15 to 60 cm tall.

Species Endemic Range

This species is endemic to the South and Central Appalachian regions of the United States, occurring in the states of Virginia, West Virginia, North Carolina, South Carolina, Georgia, Kentucky, Tennessee, and Alabama.

Elevation Distribution

It is abundant in Appalachian mountain regions, and has also been rarely reported from low elevations in the Western Piedmont Foothills.

Wet Habitat Types

It is typically found in dense forests near cold water sources, including wooded seepages, streamsides, spray cliffs at waterfalls, and brookbanks.

General Habitat Range

It is commonly observed in groves, stands, seeps, screes, and outcrops, as well as other wooded and riparian environments, and less frequently occurs in rich cove forests.

Elevation Range

It can be found at elevations between 0 and 700 feet, and is most often found at 500 feet.

USDA Conservation Status

It is labeled L48 N by the United States Department of Agriculture Natural Resource Conservation Service, indicating it is a native species of the continental United States.

Heliophily Value

It has a heliophily value of 3 on the Heliophyte Index, which measures a species' sunlight requirement for growth and reproductive success; a value of 3 indicates it is adapted to or tolerant of shaded environments.

Wetland Indicator Status

It is categorized as a Facultative Wetland (FACW) species on the National Wetland Plant List, meaning it is likely to occur in wetland environments, and acts as an indicator of wetland biomes, particularly in the Eastern Mountains and Piedmont regions, and areas of the Atlantic and Gulf Coastal Plains.

Observation Period

Thalictrum clavatum is most commonly observed from early April to mid-July, though rare earlier sightings have been recorded in early August.

Flowering Period

It produces white flowers during spring and summer, between May and July, blooming after the spring wildflowers of rich cove forests have already flowered.

Fruit Development

Achene fruits develop after flowering.