Handsome Harry's long yellow anthers open only at the end. The pollen is smooth, but not easily dislodged. Certain bees, like bumble bees, can use their flight muscles to vibrate the pollen loose. This is also called sonication, because of the buzzing. About 8% of plants are pollinated this way, including tomatos. Greenhouses have to use electric vibrators or introduce bumble bees to get tomatos to fruit. Australia has no buzz pollinators, and it is difficult to grow tomatos there.