The sex lives of Christmas trees are a lot more interesting than their wholesome image suggests. Not necessarily because they’re into kinky stuff, but because they are a certain type of conifer that rely on the ancient practice of “tree sex” to reproduce.

There are many different types of trees used as Christmas decorations. The most common and original species is the Norway spruce. However, a whole range of spruces, pines and firs are also fairly widely used – all of which belong to the conifer division.

So what exactly are those pine cones you hang up in your house around Christmas time? They’re the conifer trees' reproductive organs. Pine cones are the tree’s lady bits that hold all of their seeds. The males, on the other hand, create pollen that they distribute via either the wind or passing animals in the hope of “knocking up” the female trees.

The pollen needs to get into the female’s pine cones to fertilize. If these trees manage to get lucky, the cones will close up until the seeds are fertilized and mature. Once ready, they will open again and release the fertilized seeds.

On a side note, there’s even evidence that these trees can sometimes change sex – they were cool with that millions of years before human society was.

But what’s the advantage of all this compared to the method employed by flowering plants? This video from Deep Look provides some more insight into "the sex lives of Christmas trees" (don’t worry, it is “safe for work”).