Many wild weeds are considered problematic pests by gardeners and farmers because of their tendency to sap moisture and nutrients away from other plants near them. Some weeds, however, are grown deliberately. The seeds of the wild mustard weed, for instance, are harvested, ground and combined with other ingredients to make table mustard.
Wild Mustard Classification
Most wild mustard weeds are winter annuals, though some varieties are summer annuals. The category "annual" means that the weed experiences its entire life cycle from germination to bloom and dormancy in the span of one year or one season. Winter annuals are those annual plants that germinate in the winter, survive the entire winter and bloom in either late winter or spring. Summer annuals, on the other hand, sprout, reproduce and die off all within the span of the warm summer months.
Wild mustard weeds grow wildly through the United States. The weed's foliage is made up of egg-shaped leaves that are usually 2 to 8 inches long and up to 1 1/2 inches wide. Mustard flowers are typically yellow and four-petaled; they grow in clusters at the end of the mustard branches and are usually 3/4 inch wide.
Wild Mustard vs. Other Mustard Weeds
Wild mustard is often confused with other mustard varietals, such as Yellow Rocket (Barbarea vulgaris) and Wild Radish (Raphanus raphanistrum) since they closely resemble wild mustard at maturity. But wild mustard is distinguished from wild radish by the absence in wild mustard of wild radish's stiff hairs lining its leaves. Yellow rocket has a large lobe on each leaf, making it easy to distinguish from wild mustard weed.
Spotting Wild Mustard
Wild mustard weeds can be identified by the presence of a few essential characteristics. Wild mustard has the yellow flowers that are typical of any mustard plant, but in addition to the characteristics already described, the wild mustard weed has wavy, lobed leaves toward the bottom of the plant and smaller, unlobed leaves at the top. If you notice these characteristics in conjunction with a winter life cycle, the chances are good that you have found some wild mustard weed.