It grows along the Carson River and in waste places in Nevada. Tall whitetop is a prolific plant, capable of producing more than 6 billion seeds per acre. Although most are shed in the fall, some seeds remain on the plant through winter. Seedlings of tall whitetop are difficult to recognize, as they look like seedlings of other mustards. This weed expands by creeping underground roots that grow 3 to 10 or more feet long, and send up shoots to form new plants.
Plants can grow from parts of perennial roots as small as one-tenth of an inch in thickness.
The large amounts of semi-woody growth produced by tall whitetop may persist for several years. Its distinctive light tan color is easily identified from a distance. This thick residue makes it difficult to spray new growth as the herbicide is trapped on the dead overgrowth before it can reach the leaves. It is also difficult to walk through and move equipment across. Tall whitetop first infests wet sites along streams, rivers and wetlands.