|ODA rating: B
USDA Symbol: CACH10
Oregon lens podded white top distribution
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Images courtesy of California Department of Food & Agriculture
If images are downloaded and used from the ODA web site please be sure to credit the photographer.
Lens-podded whitetop is single-stemmed, erect perennial herbs and grows less than knee high. Flowers are generally dense, white and typically flat-topped. Leaves are shaped like a lance, up to four inches long and one inch wide and it clasp the stem and have a heart shaped bases. The infestation of this species is distinguishable by the large white patches in fields.
This very invasive weed forms dense patches that can completely dominate meadows and fields, resticting the growth of other species or degrading pastures. The species is not toxic to livestock but neither is it grazed. It negatively affects native fauna as well and very strong competitors for nutrients and moisture. Whitetop is a common weed species on alkaline soils, but is not restricted to them. It has deep, long-lived taproots that store sugars.
Lens-podded whitetop is native to central Europe and western Asia. It has now spread to all continents and is particularly common in many parts of North America. Common method of dispersal is through movement of root fragments in mud carried by livestock, vehicles and equipment. Seed dispersal is also commonly spread by hay and forage such as cut alfalfa and by flowing water.
Distribution in Oregon
The first record of lens podded white top in Oregon is 1925 in Wheeler county. This species is less common than Cardaria draba but thousands of acres can still be found in Oregon.
No approved biological control agent is available.