The creeping dogwood, a species similar to the red-osier dogwood, but which is pollinated by large bees, such as bumblebees, showed no significant decline in fecundity.

• 类似红柳山茱萸的爬行山茱萸，受大型蜜蜂如熊蜂的传粉，却没有显示明显的繁殖力下降。