Scientific Name

• The scientific names of many plants are being changed and reassigned because of DNA studies that were unavailable when earlier systems of taxonomy were devised. The scientific name for wild mustard is usually listed as Brassica kaber although it may be listed as Brassica arvensis or Sinapsis arvensis. Sinapis is a genus related to the Brassica genus of the Brassicacease family of plants. The Brassicacease family of plants contains 300 genera and is also known as the cabbage or mustard family. Older sources call it the Cruciferae plant family. The International Code of Botanical Nomenclature accepts both family names.
  
  

Foliage

• Wild mustard grows from 1 to 3 feet high. Its first hairy leaves are elliptical with wavy edges. Mature plants have glossy green, egg-shaped or oval leaves with sunken veins. The leaves are about 1/2 to 2 inches wide, 2 to 8 inches long and alternate on the stem. Leaves at the bottom have petioles or stalks, with toothed or serrated edges, and they are deeply lobed, or indented. Farther up the stem, the leaves become smaller, and they lack stems or lobes.
  
  

Flowers

• Wild mustard grows clusters of yellow flowers. Each blossom is about 3/4-inch in width and has four petals. Its fruit, called siliqua, are capsules of two fused carpels that are twice as long as they are wide. A carpal is a form of leaf that bears the ovule, which contains the plant's seed.
  
  

Listed as Noxious

• The U.S. Department of Agriculture lists wild mustard as Sinapis arvensis L. and classifies it as a weed. Iowa lists wild mustard (Brassica arvensis) as a secondary noxious weed. Michigan lists mustard (Sinapis) as a noxious weed. Ohio lists wild mustard (Brassica kaber var. pinnatifida) as a prohibited noxious weed.