Recent studies have demonstrated that animal pollinators have considerable potential to effect most floral traits. Here,we report different pollination effectiveness caused by various insect visitors in a hermaphrodite plant, Liriodendron chinense (Hemsl.) Sarg., can lead to changes in sex allocation measured by pollen and ovules production. In population G bees are the most abundant visitors, but flies in population H and Z. Pollen transfer by bees was much more effective than by flies. In population Z...