Desire Paths

The white paint on the trunks helps reflect sunlight and prevents the tree’s bark from getting too much sun. In the winter, an overabundance of sunlight can cause thawing of critical tissues under the bark. They then can refreeze when temperatures drop, leading to trunk cracks and fissures. These wounds are perfect entry points for pests and diseases.

https://www.bobvila.com/articles/why-paint-trees-white/

Are they painted? It looks like they're wrapped in something to me, I'd also like to know why. My first thought was to protect against cold or weather.

In europe on a pond I’m managing we have select tree bottom parts painted with silica paint which happens to be white to protect as much as possible against beavers and shit. It is apparently not nice on their teeth's.

People say it's keep them safe from bugs. I think the link the other person shared sums it up pretty well.