Yellow root (Hydrastis canadensis), also called goldenseal, is a perennial groundcover native to Eastern North America's woodlands. Traditionally Native Americans used various plant parts, especially the rhizome roots, for medicinal purposes. All parts of the plant contain alkaloids that are toxic, so this plant should not be consumed. Slow-growing yellow root survives where the winter temperatures drop down minus 20 degrees F but no lower than minus 30 degrees F.
Yellow root grows in moist soils, sandy to clay, which are rich in organic matter. These soils do not flood or remain soggy after typical rainfall. The plants prosper in regions or landscape areas that are shady, moist and cool in the summer months according to the "A-Z Encyclopedia of Garden Plants." Yellow roots typically are found in partially or dappled shade under woodland trees, rarely in wind-swept and fully sunny spots.
Deciduous in cold winter months, dying back to overwinter underground, yellow root is readily identified during the growing season. In summer, the plants are at their maximum height of no more than 12 inches. Each plant ranges in width from 6 to 10 inches. Seedlings may be much smaller initially, only 2 to 4 inches tall and slowly getting taller and wider.
The leaves of yellow root plants are distinctive. In spring, a basal leaf is present but may or may not fade away by midsummer, according to the Flora of North America database. The primary feature on a plant is a slender, hairy herbaceous stem that branches into two. Each branch carries a rounded, crinkly, hairy green leaf with five to nine deep lobes. The leaf edges are often with doubled rows of tiny teeth. The upper leaf in the pair is usually smaller than the lower leaf, which can be as large as 10 inches in diameter by late summer. Autumn frosts kill back the leaves and stems to the ground.
Yellow root blooms in midspring, which across its native North American range tends to fall in the months of April and May. In cool regions, the flowering can occur as late as June. Each plant produces just one flowering stem that extends upward from a leaf center. The flower bud has three sepals that drop away to reveal a petal-less blossom with many white stamens that looks like a loose pompom or spider. The pollen-carrying anthers are pale yellow and found at the tips of the white filaments.
By midsummer, the flowers have developed into a small aggregate fruit that looks like a red raspberry. It comprises multiple tiny berries that are fused together, each contains one or two seeds, according to the Flora of North America. The fruit is not edible. The singular fruit measures no larger than 1/2 inch across.
Since the yellow root is becoming increasingly rare across its native range because of woodland habitat loss, do not dig up to identify natural stands of plants. The yellow root grows from a tough knobby rhizome, or horizontal swollen stem, with many thick, tough fibrous roots that spread outward into the soil. Both the rhizome and roots are a bright sulfur yellow.