Blecker, L., Creech, E., Dick, J., Gephart, S., Hefner, M., Kratsch, H., Moe, A., Schultz, B. 2020, Nevada Noxious Weed Field Guide – Perennial pepperweed, Extension, University of Nevada, Reno, Field Guide

Stem

  • Up to 6 ft. tall, semi-woody, waxy and lacks hair (glabrous); many stems can arise from each crown; often branched near top; branches arise from leaf axils
Photo of perennial pepper weed plant
 

Leaves

  • Alternate, oval to lance-shaped, mostly 3-12 in. long, 1-3 in. wide, green to gray-green, lack hair and waxy; edges (margins) smooth to toothed and can also be curled; leaf bases DO NOT clasp stem; lower leaves larger than upper leaves
Photo of perennial pepperweed rosette
 

Flower

  • Small and white with 4 petals; arranged in dense clusters at the tips of stems
  • Seed pods are round, flattened, less than 0.1 in. diameter, usually covered with hairs; each seed pod has 2 chambers, each with 1 seed
Photo of perennial pepperweed with white flowers
 

Root

  • Creeping root system
Photo of perennial pepperweed bush with white flowers

Other

  • Grows best on moist sites; often found in floodplains, pastures, meadows, hay fields and along waterways; known to occur throughout Nevada
  • Perennial; reproduces by roots and seed
  • Also known as tall whitetop
 
Photo of a field of perennial pepperweed

Control

  • Mowing, digging, tillage, burning and grazing established stands is NOT effective 
  • Apply chlorsulfuron, imazapic, imazapyr, or metsulfuron to actively growing plants through early-bloom; 2,4-D and glyphosate at bud to flower can be effective if repeated for several years

Learn more about the author(s)

Heidi Kratsch
Heidi Kratsch
 

Also of Interest:

 
The response of perennial pepperweed (Lepidium latifolium) to physical and chemical mowing and subsequent herbicide treatment. Schultz, B.W., Creech, E., and McAdoo, J.K. 2014, UNCE Special Publication. SP-14-02. P.19.
Response of seedling and one and two year-old perennial pepperweed (Lepidium latifolium) plants to herbicide control. Schultz, B.W. 2012, Journal of the NACAA. 5:1.
Differential Herbicide Effectiveness on Adjacent Populations of Young (Seedling) and Mature Perennial Pepperweed (Lepidium latifolium). Schultz, B.W. 2011, Journal of NACAA. 4:2.
Nevada’s Priority Agricultural Weeds: Perennial Pepperweed
Perennial pepperweed is a long-lived perennial weed native to Eurasia. This weed arrived in North America as an ornamental plant, but subsequently spread throughout the Western states, where it inhabits many different environmental settings.
 B. Schultz, S. Foster 2021, Extension, University of Nevada, Reno, SP-21-01