Selected Plants of Navajo Rangelands

Take care of our Navajo Rangelands

Os si tsóh
(a.k.a. Tall whitetop, giant whiteweed, perennial pepperweed, broadleaved pepperweed, clasping pepperweed, Lepidium virginicum)

Inflorescence with small white flowers and some new seeds

Pepperweed is a highly invasive non-native herbaceous perennial. It can invade a wide range of habitats including riparian areas, wetlands, marshes, and floodplains. It adapts readily to natural and disturbed wetlands. As it establishes and expands, the plants create large stands that displace native plants and animals.

In addition to impacting alfalfa and pasture production, it has been reported to adversely affect food quality and nesting habitat for native birds.

Inflorescences that have gone to seed
Small leaves and flower clusters with buds and white blooms
Plants long after they have gone to seed. In this state, they have a pale, brushy appearance.
Many white flowered round plants covering sandy ground
Close up of white flowered stems

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