Sulfur Cinquefoil
Potentilla recta
Washington State Classification
Class B — Control Required (Designated)
Sulfur cinquefoil can form monocultures over large areas of rangeland, roadsides, waste places and fields.
Required control in Region 1 (all western Washington counties)
Quick Reference
Identification
Growth Habit
Sulfur cinquefoil is a perennial species with a woody rootstock, reaching one to three feet in height.
Leaves
Leaves are rough and hairy. They have 5 to 7 palmately arranged leaflets that are 2 to 4 inches long by 1/2 to 1 inch wide and have toothed margins.
Flowers
Flowers are found on flat topped inflorescences. Petals have five light yellow petals and a dark yellow center.
Fruit & Seeds
The fruits are achenes, which are dark brown, with lighter, prominent, branched ridges, and narrow, winged margins.
Impact
Sulfur cinquefoil can form monocultures over large areas of rangeland, roadsides, waste places and fields. It is a strong competitor with grasses in rangeland areas. It has a high tannin content and is unpalatable to most wildlife and livestock.
Ecology & Spread
Habitat
Sulfur cinquefoil is found on open grasslands, shrubby areas, open forest and logged areas, roadsides, waste areas and abandoned fields. Please click here to see a county level distribution map of sulfur cinquefoil in Washington.
Spread Mechanisms
Reproduction
Sulfur cinquefoil reproduces by seed, but it can be spread by roots if they are moved by tillage or on soil moving equipment.
"
Control Methods
Mechanical
- Mowing is not effective and roots will send up new shoots. In productive areas, cultivation with annual crops will control sulfur cinquefoil. Hand pulling or chopping is also effective if care is taken to remove the root crown.
Biological Control
- Forty-seven species of insects are associated with sulfur cinquefoil in the northeastern U.S., but because of close genetic relationship between cinquefoils and strawberries there is concern with bioagents attacking non-targeted plants.