TIL that squirrels plant thousands of trees per year simply by forg...

And that is just in the United States! It is estimated that millions of trees are planted world wide each year by squirrels accidentally forgetting where they hid their nuts!

Squirrels spend most of their life foraging for food. They climb trees and scan the forest floors in search of nuts and seeds. They hide most of these seeds and nuts in order to store them for later and also to make sure they have enough food to eat during winter when food is much more scarce.

Unlike some birds, squirrels do not have a "mental map" that helps them remember where they bury their stored food. Instead they rely on a strong sense of smell to help them locate buried food. As you can imagine some buried food gets missed. Birds that tend to store food rely on memory to locate their stored food as they do not have a strong sense of smell.

Birds have also been known to "spy" on squirrels and watch where they bury their nuts in order to dig them up later and steal them. Squirrels, however, have become wise and adapted to this as they have been known to do "fake burials" of nuts in order to trick the birds. The birds then dig up several empty sites and soon give up on stealing the squirrel's stash.

These fake burials, stolen food, and forgotten storage locations are what often turn into trees later on...

A couple other interesting facts about squirrels:

Squirrels can smell food under a foot of snow.
Their front teeth never stop growing.
Newborn squirrels are born blind.
Squirrels may lose up to 50% of their buried food to thieves.
Squirrels pack on weight to stay warm during the winter.
Squirrels will adopt a baby squirrel as their own if they find one that is abandoned.