Click any image in the slide to see a larger version.
Scroll down to read accompanying notes.
Slide 4 of 18
Honey bees avoid landing on the keel and tripping the flower; apparently to avoid getting hit in the head by the column. Rather, they collect nectar by sticking their tongues in the base of the flower from the side of the keel. When they do this, the flower is not tripped. Thus, honey bees don’t pollinate alfalfa well.
Flowers wilt within hours when they are tripped, but will stay open for about a week if they are not tripped. This is important in the dynamics of alfalfa pollination, as my research has shown (see slide show Part 2).
So, there is essentially one chance for the flower to get cross pollinated, and one chance for the bee to collect pollen and nectar from the flower.