War on Weeds—weeds are everybody’s problem
Photo courtesy of Eric Coombs, Oregon Department of Agriculture, Bugwood.org
THE ISSUE: Mediterranean sage
Mediterranean sage (Salvia Aethiopis L.), a biennial, native to Europe that was likely introduced as an ornamental or as a contaminate in seed. It is not palatable to livestock or wildlife, allowing it to outcompete palatable plants. It typically invades rangelands, but it can also establish in agronomic fields, roadsides, and pastures.
Mediterranean sage can grow up to 3 feet tall. Wooly hairs on leaves and stems give young plants a soft appearance, as they mature, they produce fewer hairs and develop prominent veins. Mediterranean sage forms rosettes that can be 1 to 4 feet in diameter. Stems are square and multi-branched; clusters of flowers are housed at the end of stems. Flowers are yellow to white, ½ -1” wide, and each has 5 petals. A mature mediterranean sage plant can produce up to 100,000 seeds in one year. Seeds are dispersed as the plant is blown in the wind as a tumble weed.
Integrated Pest Management (IPM) Options:
• Prevention— Learn to identify this plant. Never transport unknown plant material. Always plant clean seed!
• Mechanical— Hand digging may be effective for small infestations. be sure to cut the root at least 2-3” below the soil surface. Digging must occur after the rosette stage but before seed is produced.
• Cultural— Use proper grazing techniques to encourage desirable plant growth, do not over graze.
• Biological— Root-Crown Weevil (Phrydiucus tau), has been found to reduce the spread of this weed. It feeds on the root crown, preventing the weed from bolting.
• Chemical— There are several herbicide active ingredients that can effectively control this weed. Clopyralid controls existing plants but will not provide residual control like Picloram. Metsulfuron + 2,4-D, or Metsulfuron + Glyphosate are effective at controlling this plant from the rosette stage to early flowering. Use a surfactant, its hairy leaves make it difficult for herbicides to contact the leaf surface. Always read and follow herbicide label directions!
Justin Hatch, University of Idaho Extension Agriculture Educator in Caribou and Bear Lake Counties. 208-547-3205
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