Perennial Pepperweed

Description

Perennial pepperweed was introduced to North America from Eurasia and is a deeply rooted perennial forb with waxy coated leaves and stems. This member of the Mustard family can grow up to two metres tall.

Type

Perennial

Habitat & Impacts

Grows on well-drained, often saline sites in unshaded areas. This species can be very invasive and invades pastures, croplands, meadows, and riparian areas. Habitat quality in riparian areas can be seriously impacted. Croplands and pastures may have reduced yields and harvest will be contaminated by pepperweed seeds.

Method of Spread

Perennial pepperweed reproduces by seed or by root fragments. Seed production is moderate, and seeds do not significantly bank in soil. Seeds are dispersed by wind and water and most often land close to the parent plant.

Location

Currently only one recorded site in the southern part of the region on Highway 97 at 91 Mile.

Mechanical

Mowing and spring burning can control perennial pepperweed density if done prior to seed set. Hand pulling is difficult as rootstocks are deep-seated and extensive.

Chemical

A number of herbicides are effective at controlling this species, including metsulfuron-methyl., dicamba, glyphosate, imazapyr, and glyphosate/2,4-D.

Biological

No biocontrol agent is currently available for perennial pepperweed in British Columbia.

CCCIPC Priority & Treatment Strategy

Priority 1 (new invader) throughout the region except for Central Coast where it is ranked as N/A (not ecologically suited to the area). All known and new infestations of perennial pepperweed will be targeted for elimination. Heavy monitoring around the one existing site is required to ensure that new infestations do not become established.

Local Level

Hand pulling, cutting, chemical.

Landscape Level

Chemical.