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Dwarf Mistletoe

a close-up on dwarf mistletoe growing on a pine branch

You might be familiar with mistletoe, having perhaps spent numerous holiday parties hoping to corner your secret crush under its sprigs. Mistletoe is a parasite that infects trees. There's also a type of mistletoe, Viscum scurruloideum that is especially interesting because of how different it is than most plants.

As if ordinary mistletoe didn't already spell trouble for trees, its cousin the dwarf mistletoe (Arceuthobium) is a huge problem.

Sugar Thief

Your Christmas variety mistletoe takes water and minerals from the tree it grows on, which can cause its limbs to die back. Even worse, the dwarf mistletoe takes the tree's sugars, leaving it drained and susceptible to disease and infection.

Trees infected with dwarf mistletoe also suffer from poor wood quality and reduced growth rate. To make matters worse, the dwarf mistletoe is wildly successful. In some forests in the Rockies, infection rate may be as high as 80 percent.

The Sex Life of Arceuthobium

What makes the dwarf mistletoe so successful?

Simple! Its sex life. You see, regular mistletoe seeds are spread around by birds that eat the fruit and then conveniently spread the seeds along with their feces. Which means instant fertilizer.

In contrast, the dwarf mistletoe needs no help spreading its seeds because it has spring-shaped cells that act like catapults to eject its seeds.

Basically, the dwarf mistletoe stores water in these cells until the pressure builds up and the fruit explodes, sending the seeds as far as 65 feet into the air. The seeds go far, but not so far that they're likely to overshoot the tree stand entirely.

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