The tradition:

   Kissing under a sprig of mistletoe has been around for hundreds of years. The proper procedure of kissing under the mistletoe is to take one berry off for every kiss received. When all the berries are gone, so are the kisses.

What is mistletoe, and where does it come from?

   Mistletoe is a parasitic plant that grows on a number of different tree species. Mistletoe plants are either male or female. The female plant will produce berries, and the male plant will produce pollen. The berries can be very toxic if consumed by children, or pets. Mistletoe is pollinated through the cycle of animals consuming the plants.