Basin wiki · Plants
Sahara mustard
Brassica tournefortii · Asian mustard
A winter annual that greens up fast on disturbed soil, then dries into fine fuel under the native shrubs.
Where you'll see it
Sahara mustard shows up first along roads, off-highway tracks, graded pads, and old burns: Johnson Valley, Wonder Valley, highway shoulders, and the edges of the park. A wet winter turns it from a roadside weed into a continuous carpet. Cal-IPC ranks it high as an invasive. It germinates early, shades native seedlings, and sets a lot of seed that sticks to tires, socks, and undercarriages.
How to tell it
It is a mustard: yellow flowers with four petals, and a basal rosette of rough, lobed leaves that can be a foot across on a good plant. The stem leaves clasp the stalk. By late spring the whole plant is a pale skeleton of thin pods. London rocket and other weedy mustards occur too; the big sand-loving rosette on a disturbed desert flat is the one to learn. If you need a photo ID, Calflora’s taxon page is the comparison set.
Why fire crews care
Native creosote scrub is naturally patchy, which slows a flame. Dried mustard fills the gaps with fine fuel and can carry fire into shrubs that would otherwise have bare ground around them. That is the local consequence of a plant that looks, for six weeks, like a pretty green spring. Pulling it after it has cured does not put the fuel back in the bag.
What actually helps
Pull small plants before they set seed, and bag the seed heads rather than shaking them out on the pad. Stay on existing roads and trails so you are not planting the next patch. Wash mud off vehicles and boots after a day in a mustard-thick OHV area before you drive into intact creosote. Herbicide is a land-manager decision with label rules and neighbors; it is not a casual driveway experiment. The Cal-IPC profile is the management summary to hand someone who wants a protocol.
