''Lepidium latifolium'', known by several common names including perennial pepperweed, broadleaved pepperweed, pepperwort, or peppergrass, dittander, dittany, and tall whitetop, is a

perennial In horticulture, the term perennial ('' per-'' + '' -ennial'', "through the year") is used to differentiate a plant from shorter-lived annuals and biennials. It has thus been defined as a plant that lives more than 2 years. The term is also ...

plant that is a member of the mustard and cabbage family.

Description

''Lepidium latifolium'' normally grows to , but may grow as tall as . It has numerous woody stems, alternating waxy leaves and clusters of small white flowers. It produces small (1.6 mm) fruits which each contain two reddish seeds. It has an extensive root network, known to reach in depth, and constituting 40% of the total

biomass Biomass is a term used in several contexts: in the context of ecology it means living organisms, and in the context of bioenergy it means matter from recently living (but now dead) organisms. In the latter context, there are variations in how ...

of the plant.

Distribution

This plant is native to southern Europe,

Mediterranean The Mediterranean Sea ( ) is a sea connected to the Atlantic Ocean, surrounded by the Mediterranean basin and almost completely enclosed by land: on the east by the Levant in West Asia, on the north by Anatolia in West Asia and Southern ...

countries and Asia as far east as the

Himalayas The Himalayas, or Himalaya ( ), is a mountain range in Asia, separating the plains of the Indian subcontinent from the Tibetan Plateau. The range has some of the Earth's highest peaks, including the highest, Mount Everest. More than list of h ...

. It is an

introduced species An introduced species, alien species, exotic species, adventive species, immigrant species, foreign species, non-indigenous species, or non-native species is a species living outside its native distributional range, but which has arrived ther ...

in Australia and North America, growing throughout the United States and Mexico. It may have been introduced to the U.S. when its seed got into a shipment of

sugar beet A sugar beet is a plant whose root contains a high concentration of sucrose and that is grown commercially for sugar production. In plant breeding, it is known as the Altissima cultivar group of the common beet (''Beta vulgaris''). Together with ...

seeds.

Invasive plant

The plant is most invasive in

wetland A wetland is a distinct semi-aquatic ecosystem whose groundcovers are flooded or saturated in water, either permanently, for years or decades, or only seasonally. Flooding results in oxygen-poor ( anoxic) processes taking place, especially ...

habitats, including

riparian zone A riparian zone or riparian area is the interface between land and a river or stream. In some regions, the terms riparian woodland, riparian forest, riparian buffer zone, riparian corridor, and riparian strip are used to characterize a ripari ...

s; from there it easily spreads to other ecosystems, such as

sagebrush Sagebrush is the common name of several woody and herbaceous species of plants in the genus ''Artemisia (plant), Artemisia''. The best-known sagebrush is the shrub ''Artemisia tridentata''. Sagebrush is native to the western half of North Amer ...

. It is perceived as a threat to

salt marsh A salt marsh, saltmarsh or salting, also known as a coastal salt marsh or a tidal marsh, is a coastal ecosystem in the upper coastal intertidal zone between land and open saltwater or brackish water that is regularly flooded by the tides. I ...

es in southern

New Hampshire New Hampshire ( ) is a U.S. state, state in the New England region of the Northeastern United States. It borders Massachusetts to the south, Vermont to the west, Maine and the Gulf of Maine to the east, and the Canadian province of Quebec t ...

, prompting the Department of Environmental Services and the U.S. Fish and Wildlife Service to look for it in the

Hampton Hampton may refer to: Places Australia *Hampton bioregion, an IBRA biogeographic region in Western Australia * Hampton, New South Wales *Hampton, Queensland, a town in the Toowoomba Region * Hampton, Victoria ** Hampton railway station, Melbour ...

– Seabrook Estuary in 2008, where it is thought to have spread. The agencies were recruiting volunteers to help look for and properly remove it from this area. It is also a pest in the Monte Vista and Alamosa National Wildlife Refuges in

Colorado Colorado is a U.S. state, state in the Western United States. It is one of the Mountain states, sharing the Four Corners region with Arizona, New Mexico, and Utah. It is also bordered by Wyoming to the north, Nebraska to the northeast, Kansas ...

and

Malheur National Wildlife Refuge Malheur National Wildlife Refuge is a National Wildlife Refuge located roughly south of the city of Burns, Oregon, Burns in Oregon's Harney Basin. Administered by the United States Fish and Wildlife Service, the refuge area is roughly T-shap ...

Oregon Oregon ( , ) is a U.S. state, state in the Pacific Northwest region of the United States. It is a part of the Western U.S., with the Columbia River delineating much of Oregon's northern boundary with Washington (state), Washington, while t ...

, and many other sites.

Uses

The leaves, shoots, and fruits of this plant are all edible. In Ladakh in the Himalayas, the spring leaves are prized as a vegetable. The peppery edge or bitterness is removed by first boiling the young shoots and leaves, and then soaking in water for two days. Cooked like spinach, it makes a nutritious vegetable. The dried stems are sometimes used in flower arrangements.

References

External links

Washington State Noxious Weed Control BoardJepson Manual TreatmentPhoto gallery
{{Authority control latifolium Plants described in 1753 Taxa named by Carl Linnaeus Flora of Lebanon