Pepperweed a threat in Union County

June 24, 2013 10:06 am

Tri-County Cooperative Weed Management Area is encouraging land managers and landowners to help manage the treatment of Perennial Pepperweed in Baker and Union counties.

Tri-County CWMA received grant money this year to help combat the problem. Perennial Pepperweed is persistent and can outcompete native vegetation, according to the Tri-County CWMA. It grows in riparian, or stream side, areas, wetlands, marshes, roadsides, railways, ditches, hay meadows, pastures, farmlands and waste places. Perennial Pepperweed reportedly impacts alfalfa, pasture production and food quality.

The weed propagates clonally, but can also reproduce by seeds floating through waterways. This means it can start new infestations downstream.

The Oregon Department of Agriculture has designed the Perennial Pepperweed as a “T” target weed because of the economic threat it poses to the state. It is also designated as a class “A” weed in Union and Baker counties as a priority noxious weed.

The weed can grow from one to six feet tall. Leaves and stems have a waxy layer. White flowers in dense clusters are at the end of branches, and each flower has four spoon-shaped petals. Flowering typically occurs from early summer to fall.

Perennial Pepperweed also produces a nearly round fruit about one-tenth of an inch in diameter. Leaves are alternate, lance-shaped, bright green to gray-green and don’t have clasping bases. Basal leaves are larger than the upper leaves. The weed can form deep-seated rootstocks.

Plants with these characteristics should be reported to Tri-County CWMA at 541-523-2740. The group will treat the noxious weed at no cost with “an approved, highly effective herbicide,” according to Tri-County CWMA.