Since Charles Elton’s book The ecology of invasions by animals and plant published in 1958, Invasion ecology has grown to become an important multi-disciplinary subfield of ecology and accumulated an impressive number of hypotheses and concepts. Yet, 65 years later, invasion ecology remains a field of hypotheses in search of mechanisms.

Although lacking definitive evidence, we can be certain that the reason for invasive plant to dominant are diverse, typically extending beyond the plant itself to include complicated interactions between plant, native plant, soil conditions, soil and endophyte plant communities, herbivory, and even simple timing—being introduced at the right moment. How could ecologists pierce the heavy fog of all these interactions and propose a crucial control method on the invasive plants, which have been one of the main drivers of biodiversity loss with negative socio-economic impacts?

The data was collected by Taylor Portman as part of her master’s thesis and at Santa Rita Experimental Range with 100 years of ecological monitoring record. She selected two species, the rapidly dominating Lehmann lovegrass and its biggest victim over the past century, Arizona cottontop, and compare their “functional traits” derived from root and rhizosphere metabolomes.

My approach was to listen to the chemical whispers between plants, soil, and the environment—the metabolome where all interactions occur.  As someone trained as restoration ecologist and microbial ecologist in my PhD, this felt like learning a new language. I linked the chemicals into ecological functional traits and organize the complex metabolites in an ecological framework.

Three key patterns emerged from our analysis. First, lovegrass is a nitrogen economist.  Compared to cottontop, which has stronger signals of nitrogen processing intermediates, lovegrass roots contain abundant metabolites like glutamine and asparagine, molecules that shuttle nitrogen into shoots and leaves for rapid growth. Second, lovegrass produced fewer defensive chemicals, suggesting it has escaped the herbivory and pathogens. Third, and most striking, was lovegrass's plasticity. In the shifting conditions of different canopy environments, its metabolome rewired itself, pivoting from growth strategies in closed canopies to stress tolerance in open canopies.

Metabolites are not mere molecules—they are evidence of ecological decisions. A spike in glutamine represents a plant betting on growth; a reduction in defensive compounds reveals a calculated risk. By employing four complementary analytical methods, we overcame the limitations inherent to any single approach, creating a comprehensive view of the metabolic landscape that would otherwise remain fragmented. This study stands at a promising intersection where analytical chemistry meets ecology, where traditional field science converges with cutting-edge analytical technology, and where long-standing ecological theory finally encounters molecular evidence. As our analytical capabilities continue to advance, we can expect even deeper insights into the chemical language of invasion—potentially transforming how we predict, manage, and mitigate the impacts of invasive species worldwide. The whispers we have begun to decode may soon become clear conversations, revolutionizing our approach to one of ecology's most persistent challenges.