Baker City, OR (Zone 5b) | October 2009 | negative
Common names for this plant are Hoary Cress, Pepperwort and Whitetop. It is very invasive and becoming more of a problem every year in m...Read Morey area of eastern Oregon where it grows along roadsides, in pastures, in hayfields, cultivated fields, and in everyone's gardens. My weed book (from Idaho) lists it as a noxious weed, and states that it first appeared in North America in the late 19th century along both the east and west seacoasts, apparently having traveled in ships ballast, which included soil as well as rocks. The origin appeared to be Europe.
It spreads by seeds and roots and is a very agressive plant.
This plant is listed on the North Dakota invasive/troublesome list and this information is being distributed in a guide developed by the ...Read MoreND Weed Control Association and other agencies.
Plant Features
Perennial, up to 2.5 feet tall
Leaves clasp stem and are covered with hairs giving plant a grayish appearance
Each stem produces manyflowering branches; creates a white-top appearance
Flowers abundant, 1/4 inch wide, 4 petals
Blooms May through June
Spreads by seeds (July) and deep, creeping roots (rhizomatous)
Egg-shaped seeds
Creates monocultures
Distribution
Documented in a few areas. Grows under most conditions
Interesting Facts
Member of the mustard family
Toxic to cattle if ingested, contains glucosinolates
First year's plant roots can grow up to 12 feet laterally and producd over four hundred shoots
Common names for this plant are Hoary Cress, Pepperwort and Whitetop. It is very invasive and becoming more of a problem every year in m...Read More
This plant is listed on the North Dakota invasive/troublesome list and this information is being distributed in a guide developed by the ...Read More