''Sisymbrium loeselii'' is a species of flowering plant in the family

Brassicaceae Brassicaceae () or (the older but equally valid) Cruciferae () is a medium-sized and economically important Family (biology), family of flowering plants commonly known as the mustards, the crucifers, or the cabbage family. Most are herbaceous pla ...

known by several common names, including small tumbleweed mustard, false London-rocket, and tall hedge mustard. It is native to Eurasia, and it is known on other continents as 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 ...

and in some areas a common roadside

weed A weed is a plant considered undesirable in a particular situation, growing where it conflicts with human preferences, needs, or goals.Harlan, J. R., & deWet, J. M. (1965). Some thoughts about weeds. ''Economic botany'', ''19''(1), 16-24. Pla ...

. It is an annual herb producing a hairy, erect stem which can exceed a meter in height. The leaf blades are divided into triangular, lance-shaped, and toothed linear lobes, and are borne on petioles. The top of the stem is occupied by a

raceme A raceme () or racemoid is an unbranched, indeterminate growth, indeterminate type of inflorescence bearing flowers having short floral stalks along the shoots that bear the flowers. The oldest flowers grow close to the base and new flowers are ...

of flowers with bright yellow petals each measuring just under a centimeter long. The fruit is a

silique A silique or siliqua (plural ''siliques'' or ''siliquae'') is a type of fruit (seed capsule) having two fused carpels with the length being more than three times the width. When the length is less than three times the width of the dried fruit ...

up to 3.5 centimeters in length containing tiny seeds. This plant is

allelopathic Allelopathy is a biological phenomenon by which an organism produces one or more biochemicals that influence the germination, growth, survival, and reproduction of other organisms. These biochemicals are known as allelochemicals and can have ben ...

against other species growing around it. It produces chemicals that inhibit the

germination Germination is the process by which an organism grows from a seed or spore. The term is applied to the sprouting of a seedling from a seed of an angiosperm or gymnosperm, the growth of a sporeling from a spore, such as the spores of fungi, ...

of seeds of other species, including

bluebunch wheatgrass ''Pseudoroegneria spicata'' is a species of perennial bunchgrass known by the common name bluebunch wheatgrass. It is native to western North America. Description Bluebunch wheatgrass can grow up to tall. It can often be distinguished from other ...

(''Pseudoroegneria spicata'') and

Idaho fescue ''Festuca idahoensis'' is a species of grass known by the common names Idaho fescue and blue bunchgrass. It is native to western North America, where it is widespread and common. It can be found in many ecosystems, from shady forests to open plai ...

(''Festuca idahoensis'').Bainard, L. D., et al. (2009). Inhibitory effect of tall hedge mustard (''Sisymbrium loeselii'') allelochemicals on rangeland plants and arbuscular mycorrhizal fungi. ''Weed Science'' 57(4):386-393. It also inhibits

arbuscular mycorrhiza An arbuscular mycorrhiza (AM) (plural ''mycorrhizae'') is a type of mycorrhiza in which the symbiont fungus (''Arbuscular mycorrhizal fungi'', or AMF) penetrates the cortical cells of the roots of a vascular plant forming arbuscules. Arbuscul ...

l fungus species, such as ''

Glomus intraradices ''Rhizophagus irregularis'' (previously known as ''Glomus intraradices'') is an arbuscular mycorrhizal fungus used as a soil inoculant in agriculture and horticulture. ''Rhizophagus irregularis'' is also commonly used in scientific studies of th ...

''. The species is named for German botanist

Johannes Loesel Johannes Loesel (26 August 1607 – 30 March 1655) was a German botanist and physician who was an expert on the natural flora of Prussia. Biography Loesel was born in Brandenberg, Prussia (now Ushakovo, Russia) on 26 August 1607. He ear ...

Uses

The leaves are spicy enough to make

wasabi Wasabi (Japanese language, Japanese: , , or , ) or Japanese horseradish (''Eutrema japonicum'' syn. ''Wasabia japonica'') is a plant of the family Brassicaceae, which also includes horseradish and Mustard plant, mustard in other genus, genera. ...

but can also be mixed into salads and other dishes.

References

External links

Jepson Manual TreatmentWashington Burke Museum
loeselii Leaf vegetables {{Brassicales-stub