Northern Prairie Wildlife Research Center
A northern plant and one of the "wild parsleys," largeseed lomatium blooms in May across the two northernmost tiers of counties in North Dakota, with a few scattered records in the westernmost counties. Elsewhere, the plant can be found west to Colorado, California, the Prairie Provinces, and British Columbia, at elevations under 8,500 ft.
Largeseed lomatium is a native perennial about a foot tall from a long taproot. The rootcrown bears up to a dozen stems, but these are very short. Instead, the stems bear purplish peduncles topped with flower clusters that account for most of the plant's height. Leaves are about 6 inches long and resemble those of the carrot, but have a slight grayish tinge caused by fine hairs. Flower clusters are called umbels. Each umbel bears about 5-10 inch-long pedicels tipped with a cluster of about a dozen tiny whitish or purple-tinged flowers. The brown fruits are about one-half inch long and consist of two connected, winged, seed-like structures.
Look for this plant in dry gravelly or clayey soils. Records indicate that the species prospers under moderate or heavy grazing by cattle, likely because of reduced competition from other plants. There are no known economic uses for the plant.
Largeseed lomatium is a member of the parsley family (Apiaceae), which includes the useful carrot, parsnip, caraway, and dill, but also the deadly water hemlock. Apium is the ancient Greek name for celery. The generic name lomatium stems from the Greek lomation, "a little border" in reference to the winged fruit. Macrocarpum means "large fruited" in botanical Latin.
Largeseed lomatium was first collected in the early 1800's by the pioneer Great Plains naturalist Thomas Nuttall (1786-1859), first recognized as a member of the genus by the early systematic botanists William J. Hooker and G.A.W. Arnott, and finally described adequately for science in 1900 by John Coulter and Joseph Rose.