Pollinator visitation

We observed pollinator visits to the flowers of P. modesta during peak flowering at each site: early June, early July, and late July at the ridge, slope, and valley sites, respectively. Field observations were conducted during calm and fine periods during daylight hours (9:00 am–3:00 pm). The total observation times were 25 hours per 5 days, 12 hours per 3 days, and 14 hours per 4 days, at the ridge, slope, and valley sites, respectively. On each observation day, we arbitrary set 2 m × 2 m plot and recorded the pollinators and the number of flowers of P. modesta. Pollinators were classified into Diptera, Hymenoptera, Lepidoptera, and others during field observations, and major pollinators were collected and identified at the family or species level if possible.