Hand-pollination, also known as mechanical pollination, is a technique that can be used to pollinate plants when natural or open pollination is either undesirable or insufficient.
Hand-pollination of two gourd blossoms
Phalaenopsis pollinia (orange) attached to a toothpick with its sticky viscidium
A pollinium is a coherent mass of pollen grains in a plant that are the product of only one anther, but are transferred, during pollination, as a single unit. This is regularly seen in orchids, which