Spherically branched plants, which roll along on the wind across deserts and prairies are only familiar to Finns from cowboy films. When the seeds are ripe they break off at the root joint and leave on the wind, shaking off seeds as they go. Certain kinds of perennial tumblers are able to set down new roots and carry on growing.
Tumble mustard grows casually at least everywhere along the railway network. Its most northerly reach is beside the Kemijärvi track, and it travels even further north by road. The species is probably increasing in Finland, but the soil and the climate keep it mainly as an exotic weed around inhabited areas.
Tumble mustard forms a tall (up to 5 ft) but delicate-looking plant, with slender, much-branched stems. Its stem leaves are divided into thin, linear lobes, while the basal leaves are broader and pinnately compound.
The flowers are inconspicuous and only 1/4 inch wide. They have four usually yellow petals and four narrow, curved sepals. The seedpods are slender and long (2-4 inches). At maturity it dies, uproots, and tumbles in the wind, spreading its seeds.
This plant is useful.
How to get rid of:
To take control of Tumble Mustard, weed digging or pulling in early spring works well. Mowing is another action that will prevent the weed from flowering, making them unable to release seeds.
Tillage is a very viable option in the control of early/young Tumble Mustard. Tillage has to be able to go deep enough to cut the root at a minimum depth of 10cm below the leaf.
Glysophate is an effective chemical to help control the growth and spreading of this weed.
This herbicide needs to be used once the Tumble Mustard is established, and application should be done either pre or post-harvest, or both.