There are 27 different species of Cinquefoils (potentilla’s) found in B.C. Today we are going to talk about one of the non-native ones Potentilla recta also know as Sulphur cinquefoil. Sulphur cinquefoil is a perennial which can live up to 20 years. It spreads by seed and also vegetatively from the roots. One plant can produce around 1,600 seeds per year and survive for over 20 years.
The good news is that the seed survival is short-lived so it is not banked for more than a few years in the soil. It has light (butter) yellow flowers with five petals and the flowers form a flat top. The leaves are palmate with five to seven leaflets on each leaf.
Sulphur cinquefoil is generally avoided by grazing animals so it does very well in pastures making control of this plant very important! Good management practices in pastures such as avoiding over grazing, irrigating, seeding disturbed areas and maintaining vigorous perennial plant communities are key to preventing this plant from turning your pasture into a sea of yellow.
Sulphur cinquefoil does not survive cultivation very well. Digging small patches can be effective but because it spreads by root buds it is important to monitor where you pulled to make sure you got all of it.
Preliminary screening has been done for a bio-control agent but it is not promising. There are several herbicides that are very effective in treating Sulphur cinquefoil.
For more information on invasive plant management you can contact the Boundary Invasive Species Society at boundaryinvasives@gmail.com, 250- 446-2232 and on Facebook.