Heart-leaved Alexanders is a glabrous perennial with several to many stems clustered atop a short, woody base with fibrous roots. The erect stems are often branched and measure from 60-100 cm high. The basal leaves are long petiolate with ovate to orbicular leaves with deeply heart-shaped bases The blades are 5-15 cm long with rounded teeth along the margins. The lower stem leaves are similar but smaller than the basal leaves while those of the mid and upper stem are 3-5-parted or divided. The margins of the upper leaflets tend to be more coarsely and deeply toothed.
The inflorescence is a fairly compact umbel of many yellow flowers from 1.5-4 cm wide when in bloom. The spreading to ascending rays of the umbel are 2-5 cm long and the umbel lacks or has minute bracts at its base. The fruits which measure 2-4 mm long are elliptic or ovate in shape and laterally compressed with threadlike ribs.
Heart-leaved Alexanders may be found in moist meadows along stream banks and in low areas. It may also be found in alkaline soils in drier habitats.
Heart-leaved Alexanders may be found from southern Alberta south through the Rocky Mts. to Colorado and west through Montana and Idaho to eastern Washington, and the Willamette Valley of northwestern Oregon. It is also found southward to northeastern Nevada. This species is also found across much of the central and eastern United States and Canada.