Canadian goldenrod and its own decomposition team: one secret of an invasive plant

29 07 2026

Invasive Canadian goldenrod may harbour microorganisms within its tissues that are capable of initiating the decomposition of plant litter without substantial support from soil microbes. Research conducted by scientists from the Faculty of Biology at the University of Warsaw suggests that this invasive plant may function together with its own microbial community. Such a capacity could help Canadian goldenrod colonise new areas by reducing its dependence on local microorganisms, potentially contributing to its invasive success.

The decomposition of plant litter returns carbon and nutrients to ecosystem cycles. This process is driven mainly by bacteria and fungi. In the case of invasive species, the course and speed of litter decomposition are particularly important. Canadian goldenrod forms dense stands, displaces native plants and alters soil properties. If its litter can begin decomposing without the involvement of local microbiota, the plant may gain an advantage when colonising new habitats.

Previous studies have shown that goldenrod litter often decomposes faster than material from many native plant species. However, it remained unclear whether this was caused by microorganisms inhabiting soils invaded by goldenrod or by microbes already present within the plant’s tissues.

The researchers collected goldenrod leaves and shoots, as well as soil samples, from meadows in north-eastern Poland. Some sites were heavily invaded by the species, while at others it did not occur at all. The plant material was placed in mesh bags and incubated under constant temperature and moisture conditions. The researchers added either unfiltered soil solutions or solutions from which successive groups of organisms, including soil mesofauna, protists and fungi, had been removed. The control treatment contained only sterile distilled water.

The most striking result was the lack of clear differences between the treatments. In the distilled-water treatment, leaf mass loss was almost the same as in the treatments supplemented with soil solutions. Whether the soil came from a meadow dominated by goldenrod or from a site where the species occurred only sporadically also had little effect.

The findings support the hypothesis that Canadian goldenrod and the microorganisms inhabiting it may form a holobiont, meaning a functional biological system capable of sustaining the decomposition of dead tissues without a clear contribution from soil microorganisms. Different groups of microbes may also compensate for one another, so the absence of one group does not halt the entire process. The study also points to the potential use of harvested goldenrod biomass for composting or biogas production, which is particularly relevant given the high costs of controlling this invasive plant in the field.

The article, “Solidago canadensis and its endophytes as a potential self-degrading system during ex-situ decomposition”, was published in Plant and Soil. The authors affiliated with the Faculty of Biology at the University of Warsaw are Kamil Kisło, MSc, and Marta Wrzosek, PhD, DSc, University Professor, from the University of Warsaw Botanic Garden; Patryk Czortek, PhD, from the Białowieża Geobotanical Station; and Anna Wiewiorowska from the Institute of Environmental Biology.

Link to the publication: https://doi.org/10.1007/s11104-026-08776-1