Capitulum and rosette leaf avoidance from grazing by large herbivores in Taraxacum

Plants defense against herbivore damage is achieved through resistance and tolerance, of which resistance is composed of avoidance and antibiosis. Plants have developed various adaptations that facilitate escape from herbivory. We hypothesized that post‐anthesis prostrate scapes in Taraxacum is an adaptation for avoidance of capitulum grazing by large herbivores. To test this hypothesis, we divided flowering into the following four stages based on the external appearance of the capitulum: green bud, yellow corolla, brown corolla, and white pappus stages. We conducted an experiment in natural pasture in Mongolia to artificially raise capitula and rosette leaves of T . collinum . We measured the natural height of capitula and rosette leaves of the Mongolian pasture and urban species, T . collinum and T . ceratophorum , respectively, and of the Japanese rural and exotic urban species, T . japonicum and T . officinale , respectively. We investigated natural grazing by livestock in the field of the capitula and rosette leaves of the two Mongolian species. In Mongolia, naturally short capitula at the green bud and brown corolla stages and rosette leaves of T . collinum were not grazed. However, artificially raised capitula and rosette leaves of T . collinum and the naturally high capitula and leaves of T . ceratophorum were grazed. Short capitulum and leaf height was shown to be effective for avoidance of livestock grazing in Mongolia. In Japan, T . japonicum and T . officinale showed similar scape behavior to T . collinum and T . ceratophorum , respectively. We discuss the reasons for the capitulum behavior differences in Japan.