Sulphur cinquefoil

Identification & Biology
Latin Name : Potentilla recta
Category : Terrestrial Plants
Description :

Sulphur cinquefoil has the following properties:

  • Perennial with large, woody taproot
  • Plants are erect, 15-70 cm tall
  • One or more hairy stems
  • Leaves are divided into 5-7 hairy toothed leaflets, each 5-10 cm long
  • Flowers are pale yellow with five heart-shaped petals around a bright yellow centre

 

Sulphur cinquefoil grows very early in the spring. The plant begins blooming in mid-June and produces flowers throughout the summer if growing conditions are favourable, setting seed in late July. Above-ground portions of the plant completely desiccate by late August. Fall re-growth of basal leaves is possible and rapid under moist, mild conditions.

Look-a-likes: Sulphur cinquefoil is one of over 20 herbaceous cinquefoils in BC and can be challenging to distinguish from other native and introduced cinquefoils. It most closely resembles graceful cinquefoil (P. gracilis), a native plant which is shorter; has white woolly hair on the undersurface of the leaves; more basal leaves; deeper, less uniform leaf serrations; bright yellow flowers; and a smooth seed coat. It may also be confused with sticky cinquefoil (P. glandulosa), silvery cinquefoil (P. argentea) and common silverweed (P. anserina).

Look Alikes
Habitat

In British Columbia, sulphur cinquefoil is most common in the Southern Interior, growing from valley bottom grasslands to mid-elevation forests. This long-lived perennial infests disturbed areas, meadows, pastures and rangelands and can dominate a site within two to three years of first appearance.

Impact & Risks

The insidious nature of sulphur cinquefoil poses both a significant environmental and economic threat. Once established, this weed can produce dense populations that reduce or eliminate forage production and biodiversity. It is unpalatable to most livestock and wildlife due to a high concentration of bitter tasting compounds.

Prevention & Mitigation

The most effective way to ensure that your lands do not become infested with sulphur cinquefoil is by prevention. Here are some recommendations to prevent invasion on your property:
• Maintain your land in a healthy, vigorous condition to ensure a productive plant community; competitive perennial grasses and forbs utilize water and nutrients that would otherwise be readily available to cinquefoil.
• Follow a well-designed grazing plan; excessive livestock grazing reduces competition and favours invasive plants.
• Regularly patrol your property for sulphur cinquefoil plants and immediately treat new infestations.
• Cooperate with adjacent landowners and encourage them to control sulphur cinquefoil.
• Immediately re-vegetate disturbed, bare soils with a suitable seed mix that provides dense, early colonization to prevent invasive plant establishment.
• Clean your vehicles and machinery of plant material and soil before leaving a cinquefoil infestation.

Treatment & Disposal

Individual plants and small patches of sulphur cinquefoil can be hand-pulled. This treatment is effective only when the upper portion or crown of the root system is removed. Sulphur cinquefoil is not controlled by mowing. Although seed production may be reduced, plants develop low, bulky, spreading roots when mowed and are able to send up new shoots. Sulphur cinquefoil is not a serious invasive plant in cropland because it does not tolerate frequent cultivation. However, a single cultivation may increase sulphur cinquefoil cover.

Chemical control is also an option. Before applying herbicides, read the label for full use and precautionary instructions. Consult the most recent edition of the Alberta Agriculture and Forestry Crop Production Guide for the selection and application of chemicals to protect your crop:

No biological controls have been approved for sulphur cinquefoil in North America.

Okanagan Distribution

Priority Level Definitions

Watch For - Poses a significant threat (very high risk) and does NOT presently occur in the region OR is relatively new to the region and is very limited in extent.
High - High risk/impact; limited population with significant potential to spread in the region.
Medium - Medium risk/impact; limited distribution – broader population distribution with potential to spread further in a region.
Low - Low risk/impact; may be widespread or not, may be of concern in specific situations with certain high values – e.g. specific agriculture crops. Some species may be treated primarily with biological control agents.