Bohemian Knotweed: A History of the World’s Worst Plant
Written by Maria Goncharova, edited by Hannah Munnalall
Bohemian knotweed is a hybrid plant between Japanese and Giant knotweed, so its history is tied very closely to both of its parents’ stories.
The origin of initial hybridization of Japanese and Giant knotweed is still a mystery, with the first Bohemian knotweed samples being identified from collected specimen samples in 1872 and 1876 from an herbarium in Manchester1.
Therefore, it is most probable that the original hybridization occurred in one of the botanical gardens in Europe that housed both Japanese and Giant knotweed1. Although Bohemian knotweed was first described in 1983 in a Czechoslovakian wildlife magazine, it was identified using only morphological (physical) features3.
This posed a big problem because, as a hybrid, Bohemian knotweed presents a mixture of physical features from Japanese and Giant knotweed4. Because of this, there is a high chance that Bohemian knotweed was misidentified as either of its parents in the past.
In fact, to this day many people still misidentify Bohemian knotweed. This, combined with the fact that Bohemian knotweed has historically garnered little interest, has allowed Bohemian knotweed to grow quietly in the shadow of its parents as a hidden villain.
References
1Thiébaut M, Nicolas S, Piola F (2020). “The fad for Polygonum will fade away!”: Historic aspects of the propagation and success in France of the Reynoutria complex based on archives. Botany Letters, 1-14.
2Anthony L (2017) The aliens among us: how invasive species are transforming the planet and ourselves. Yale University Press
3Bailey JP, Child LE, Conolly AP (1996) A survey of the distribution of Fallopia x bohemica (Chrtek & Chrtkova) J. P.Bailey (Polygonaceae) in the British Isles. Watsonia 21:187-198.
4Barney JN, Tharayil N, DiTommaso A, Bhowmik PC (2006). The biology of Invasive alien plants in Canada. Polygonum cuspodatum Sieb. & Zucc. [= Fallopia japonica (Houtt.) Ronse Decr.]. Can. J. Plant Sci. 86: 887-905.