B. tournefortii is an erect annual herb that has stems that can be from 10 to 100 cm tall, and a well-developed sturdy taproot system. It has a good number of primary stems and a large number of secondary stems that can be as high as 40. The size of the herb can vary considerably depending on soil moisture (Pratap and Gupta, 2009). The lower stems are densely covered with stiff bristles (Graham et al., 2005).
Related invasive species
- Brassica tournefortii
Related Farm Practice
- Soil
B. tournefortii is a widespread species of mustard, commonly known as African mustard or Sahara mustard. Native to Africa, Asia and Europe, it has spread globally and naturalised in North America, Australia and New Zealand. It is a highly invasive annual herb and is recorded as negatively affecting native species in some US states and Australia. Its fast growth rates enable it to monopolize soil moisture and light and mature before native wildflowers. B. tournefortii is often the dominant species in areas of usually diverse flora. CalEPPC (1999) lists the species as ‘regionally most invasive wildland pest plant’. Some factors may increase its invasive capability, for example in the western Sonoran Desert of California, USA, B. tournefortii quickly invaded areas of natural disturbance where soils were young while older geological surfaces were less vulnerable to invasion. Another study in New South Wales, Australia, found that rabbit mounds enhanced the germination of B. tournefortii seeds.
Australian Oilseeds Federation (2015) reported that B. tournefortii can contaminate canola oil crops, reducing yield through competition, and compromising oil quality.