War on Weeds—weeds are everybody’s problem

Redstem filaree (Erodium cicutar-ium) is a winter annual or biennial that forms a low growing, densely matted plant with fern-like leaves in a rosette. Because of its prostrate growing habit, it prevents the ger-mination of desirable plant species.Preferring sandy soils, redstem filaree inhabits dry pasturelands, land-scapes, and turfgrass. Redstem filaree also withstands heavy grazingpressure.

Redstem filaree has reddish stems and are covered with fine hairs. The flower stalk supports two to twelve vibrant pink/purple flowers with five petals and a long, beak-like fruit.The leaves are opposite and finely divided with toothed or lobed margins. The root system is a shallow taproot with fibrous secondary roots.

Integrated Pest Management

(IPM) Options:

• Cultural – Prevention is the best control of redstem filaree. Bare ground invites redstem filaree. In rangeland or pastureland plant native forbs and grasses. Contact your local Natural Resource Conservation Service for seed mix recommendations.

• Mechanical – Hand pulling or digging when soil is moist, making sure to get the roots to prevent re sprouting is effective. Removing flowers before the plant sets seed is also effective. Be sure to place all plant material in a bag so as not to spread seeds. Any typeof tillage to the area can also be effective.

• Biological – Redstem Filaree is grazed by many animals especially sheep. Chemical – Herbicides should be applied during seedling and rosette stages to have the greatest success. Metsulfuron at a rate of.33 oz of product/acre + .025% v/v non-ionic surfactant can be used on rangeland and pasturelands. Another option is 2 pints of 2,4-D and 1 pint of dicamba per acre. Both recommendations are based on equipment with an output of 30gallons per acre. Always read and follow herbicide label directions!

Tom Jacobsen, University of Idaho Extension Educator in Fremont County. (208) 624-3102 [email protected]