Lots of fruits are out of season here in the northern hemisphere thanks to a rather harsh winter and a visit from our old friend, polar vortex.

But recent freezing rain in Michigan led to the production of a rare psuedo-crop: the ghost apple.

The above photos come from Andrew Sietsema, a former horticulture student at Michigan State University, who told WOOD-TV that the apple-shaped ice shells formed when the frozen precipitation coated the apples.

When he pruned the trees, the shaking branches caused many of the icy apples to fall off, but in a few cases the entirety of the mushy, rotten apples just slipped through the bottom of the frozen shell.

It's likely that the recent arctic blast from the polar vortex played a role in this unusual phenomenon.

The sugar and acid content in fruits lowers the temperature at which they freeze by a few degrees, but the longer they're exposed to extreme cold, the worse the damage.

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