Mistletoe (Phoradendron serotinum), an evergreen commonly used as a Christmas decoration, is traditionally a symbol of fertility, which is why kisses are exchanged beneath its boughs. Being a parasitic plant, mistletoe is generally propagated by birds that, after eating the seeds, make deposits that land on host trees—the built-in fertilizer is ideal for getting growth off to a fine start.
In fact, the word mistletoe comes from the Old English for “turd on a twig.”
But a kissing cousin dwarf variety, Arceuthobium spp., is actually a more virile member of the family with a much more impressive reproductive technique: a water pump seed ejection system. Coil-shaped cells in the fruit store water, building up pressure over time. Eventually, typically around Labour Day, the fruit explodes, shooting seeds up to 20 metres away.
Unfortunately, dwarf mistletoe’s prolific procreation has resulted in the destruction of stands of commercial timber in parts of North America, particularly in the Prairies and British Columbia. Ironically, the plant’s unusual sexual habits could lead to its demise, as researchers at the University College of the Cariboo in Kamloops, B.C., are looking into ways of using the unique technique to destroy the parasite while protecting the host trees.