EPPO Global Database

Ambrosia artemisiifolia (Asteraceae: EPPO List of Invasive Alien Plants) is an annual weed native to North America. In Europe a single plant can produce up to 18 000 seeds which can remain dormant in the soil seed bank for up to 39 years. The persistence of the soil seed bank can compromise the efficacy of control measures and sustainable management over the long-term. In the current study the soil seed bank was sampled at sites in a roadside population in Eastern Australia before and after a three year management regime based on mowing. The management regime consisted of four treatments plus a control (not mown) where each treatment was applied to a 20 x 0.5 m area within the population. The four treatments were (1) two cuts – one before the onset of flowering and the second at the beginning of the seed set, (2) two cuts – one after the beginning of female mass flowering and the second at the start of seed set, (3) three cuts – one before the start of flowering, the second before the onset of male mass flowering and the third at the beginning of seed set and (4) three cuts – one before the start of flowering, the second after the beginning of female mass flowering and the third at the beginning of seed set. After three years, treatments 2, 3 and 4 decreased the soil seed bank by 80 %, 60 % and 45 %, respectively, compared to the control. The most effective mowing regime to reduce the soil seed bank of A. artemisiifolia as indicated by this study consists of one cut just after the beginning of the female flowering followed by a second cut 2 – 3 weeks later (at the beginning of the seed set).