Wild mustard Brassica kaber
IDENTIFICATION – Also known as charlock, wild mustard is found almost everywhere in the United States and Canada. In the spring, you can’t miss the clusters of bright yellow, four-petalled flowers on plants with small bristles on the leaves and stems. You may have a harder time identifying the plant when the flowers are gone because the lower leaves don’t always look the same. Sometimes they’re lobed, but often they just have coarse teeth on the edges. In midsummer, the plants produce seeds in elongated pods with “beaks” at the end. Wild mustard has a very short life cycle, acting as an annual or a winter annual (coming up in the fall, living through winter, and setting seed in spring). Wild mustard can be toxic to animals if they eat enough, although birds eat the seeds without ill effects.
FAVORITE CONDITIONS – You’ll find this weed in sun just about anywhere in any soil — along the road, in gardens and among crops. Listed as a noxious weed in some northern states and Canada, it invades cultivated mustard and canola fields.
CONTROL – The seeds of wild mustard can stay viable in the ground for a long time, so it’s important to pull or hoe it before it has a chance to set seed. As with most annuals, it’s shallow-rooted, so it’s easy to pull up the whole plant.