Shoe trees are instruments that are inserted into shoes to help maintain the original shoe shape, helping prevent creases and cracking. They also absorb moisture from the lining of the shoes, which can lead to degrading the materials.Click to see full answer. Keeping this in view, what is the purpose of a shoe tree?A shoe tree is a device approximating the shape of a foot that is placed inside a shoe to preserve its shape, stop it from developing creases and thereby extend the life of the shoe. Higher quality shoe trees are made from solid wood, usually cedar, which helps control odor and absorb moisture.Likewise, how long should you keep shoe trees in? 24 hours Also to know, do shoe trees really work? The short answer is yes, you should definitely use them. For your finest dress shoes, consistently putting shoe trees in them will help to maintain their shape, protect the leather by pulling out moisture, and also combat odors.Should you leave shoe trees in?Simply slip trees into your shoes after each wear. It is recommended to air out your shoes for up to an hour before inserting trees. Leave the shoes in for at least 24 hours to help shoes dry completely. If shoes are soaked from rain or otherwise wet, you will want to dry out any excess moisture first.