Sulfur (Erect) Cinquefoil (Potentilla recta)

Status:

Listed Noxious Weed In Montana

History:

First Montana Specimen Collected 1

County:

Ravalli

Year:

1947

“Sulfur cinquefoil is a perennial forb native to Eurasia. It first appeared in North America before 1900 in Ontario, Canada. By the 1950s it had become widely established in eastern Canada, the northeast United States and the Great Lakes region.  The first specimen from Montana was collected in 1947 in Ravalli County. The second and third specimens recorded in Montana were from Lincoln County in 1949 and Mineral County in 1955. Identification of the species in additional counties was infrequent until the mid 1980s when an exponential expansion seems to have occurred. As of 1993, at least 30 counties were infested in Montana, 14 in Idaho, and 5 in northern Wyoming as well as Yellowstone and Glacier National Parks.  Colonies that have expanded to dominate 100 to 1000 acres are not uncommon”. (MSU)

Habitat:

Growth Habit:

Erect, long-lived perennial, reproducing by seed, plant may form a ring of plants as the
older center dies out and new stems grow on the outside edges.

Leaves:

Palmate compound, 7 leaflets, course stiff hair on upper and lower surfaces, yellowish green; Rather than silver as in most Potentilla spp.

Stem:

One of several, 12 to 28 inches tall, branched near top, covered with hairs. Numerous leaves
along stem, few from base.

Flower:

1/2 to 1 inch in diameter, pale yellow, large yellowish green buds. May bloom late May
throughout summer.

Roots:

Woody (No rhizomes)

Seeds:

Very tiny 1/20th inch in diameter, rough.

Other Notes:

“Sulfur cinquefoil is often found in disturbed areas such as roadsides and pastures. 
Colonies of plants are also seen in undisturbed sites.”(CWMA, 7)