Ethnobotany has been, for too long, a descriptive discipline. However, ethnobotanists are increasingly calling for a paradigm shift towards the formulation of unifying theories and hypothesis-driven research in ethnobotany. Here, we formulated a theory, termed time-since-introduction theory, to explain the integration of alien plants into local pharmacopoeias in their recipient environment. This theory suggests that the factor time is paramount in determining which alien plants are more likely to be included in the medicinal flora of the areas they are introduced in. The theory relies on three hypotheses, the availability and versatility hypotheses alongside the residence time hypothesis newly proposed in the present study. We tested this theory by fitting a structural equation model to ethnobotanical data collected on South Africa’s alien woody flora. Although residence time is a direct predictor of medicinal status of alien plants, it is a better predictor when mediated through plant versatility. These findings are in support of the theory, and we consequently proposed a framework with which to understand different paths linking all three hypotheses. Collectively, our study shows the value of time in the development of ethnobotanical knowledge and fully responds to the pressing call for paradigm shift in ethnobotany.

: Alluvial soils naturally possess abundant soil nutrients. Nevertheless, excessive nitrogen addition and inappropriate use of nitrogen fertilizers lead to conditions where soil nutrients become immo-bilized, ultimately reducing productivity. This study investigates the potential of natural nano-material zeolite which is important land resources to improve nutrient utilization efficiency and mitigate the harmful effects of excessive fertilizer application. Specifically, the research ex-plores the incorporation of clinoptilolite zeolite and processed sewage sludge blends, alongside reduced recommended nitrogen fertilizer doses, to evaluate their impact on soil quality and plant growth. A greenhouse experiment was conducted (three-year study), comprising eight treatments with varying proportions of zeolite and sewage sludge. The efficacy of these treatments in en-hancing soil carbon pools, nutrient indices, and plant growth responses was assessed. Results in-dicate that a combination of 50% recommended fertilizer dose, 4-6% zeolite, and 5-10% sewage sludge significantly improved multiple aspects of plant growth, including leaves, tillers, culms, and panicles, leading to increased straw and grain yields. The addition of 6% zeolite in conjunc-tion with sewage sludge positively influenced plant tillering capacity. Certain treatment combina-tions exhibited a greater impact on plant height at different growth stages. For example, the treatment with 75% recommended fertilizer dose, 4% zeolite, and 5% sewage sludge significantly affected plant height at 40 and 55 days after treatment. Additionally, the combination of 50% recommended fertilizer dose, 6% zeolite, and 10% sewage sludge promoted plant height, carbon levels, and various yield parameters in later stages. Principal component analysis effectively dis-tinguished treatments incorporating zeolite and sewage sludge based on plant responses. The combination of 6% zeolite and 10% sewage sludge, along with a 50% recommended fertilizer dose, positively influenced soil carbon fractions, nutrient levels, and the growth response of rice plants.